Forecast of runoff based on the water content of the watershed snow corrected by a factor involving fall flow of the stream - Parshall, R.L. (16th Annual Western Snow Conference, 1948)
The fall flow of a stream is an indication of the soil moisture content over the entire watershed. A correction based on October, November and December flow in acre feet has been applied to the April 1 water content of the snow. This procedure is applied to many streams in Wyoming, Colorado and New Mexico to improve the accuracy of runoff forecasts. A graph is used to illustrate that the introduction of the fall-flow factor tends to produce a smoother curve than with snow survey data only plotted against runoff.Discussion by G.B. Jacobson.
Keywords: Runoff, Snowmelt, Statistical analysis

The cooperative snow investigation program - its objectives and operations - Rhodes, F.L. (16th Annual Western Snow Conference, 1948)
The Cooperative Snow Investigation Program was initiated in 1945 by the Weather Bureau and Civil Works Division of the Corps of Engineers. The main objectives include the determination of methods of evaluating maximum streamflow resulting from precipitation, and methods of forecasting seasonal an short-term streamflow, including floods. The expansion of basic knowledge of the hydrodynamic and thermodynamic properties of snow, and of meteorological, climatological, and hydrological phenomena is an essential element of the program. The organization includes the program director, the processing and analysis unit, the Upper Columbia Snow Laboratory, the Central Sierra Snow Laboratory, the Willamette Basin Snow Laboratory, and the technical director. The program is outlined in 5 major sections: seasonal totals of elements, time distribution of processes, areal distribution of precipitation, generalization and transfer of conclusions and methods.
Keywords: Cooperative snow investigations, Hydrology, Meteorology research programs, Research programs

A progress report on hydrologic research in the Wisconsin River valley - Sheerar, L.L. (16th Annual Western Snow Conference, 1948)
A brief history of a privately owned company developing a storage and river regulation system is presented. Reservoir storage was increased from 98,000 AF to 390,000 AF in 30 years time. A network of precipitation gages, snow survey courses, ground water observation wells, soil temperature, soil moisture and river gaging stations was established. Hourly, daily and semi-daily data are collected. River flow forecast procedures are in use for regulation of 21 reservoirs supplying water to paper mills, utilities along the Wisconsin River. The complexities of frozen ground, and variations in precipitation pattern are problems to be solved. A relationship between ground water levels and natural streamflow is being developed.
Keywords: Reservoir regulation, Water supply forecasting

Investigation of glaciers in British Columbia - Webb, C.E. (16th Annual Western Snow Conference, 1948)
Glacial surveys were made to determine the rate of recession or advance of the glaciers for streamflow investigations. Methods consist of setting up fixed reference marks near the toe of a glacial tongue. Annual measurements of the distance from the nearest point of the forefoot to a reference point, taking annual photographs, and trigonometric measurements of markers set out on the ice. Survey results are indicated for glaciers of Garibaldi Park, Franklin Glacier and glaciers of the Selkirk mountain Range. It is concluded that the rate of recession is not governed entirely by weather. Valley conditions and the steepness of the slope have a marked effect. The glaciers were in a stable condition until 1890, when a general recession began.
Keywords: Glaciar ablation

Empirical methods for estimating snow melt rates - Wilson, W.T. (16th Annual Western Snow Conference, 1948)
A simple formula for predicting daily runoff from snow has been developed. The basis of the formula is that streamflow form melting snow is largely a function of antecedent streamflow, heat supply and time of year. These factors are obtained statistically from meteorological data. The formula gave results accurate within 9% when used in predicting daily flow from snow at the Central Sierra Snow Laboratory for the Castle Creek drainage basin during April and May, 1945. The time of year factor was omitted in this calculation.Discussion by Walter U. Garstka.
Keywords: Runoff, Snowmelt, Statistical analysis, Water supply forecasting

Mechanized snow surveys in Montana - Work, R.A. (16th Annual Western Snow Conference, 1948)
A Tucker Sno-Cat, a power-driven over-snow vehicle, and a two man crew of trained snow surveyors were used to measure 24 snow courses extending a distance of 300 miles. The 1948 model Sno-Cat, 4-door sedan, was powered by a 95 HP Plymouth engine, and had a 3 speed transmission. The unit was equipped with sleeping bags, tent, stove, and emergency supplies for 2 men. A Dodge Power Wagon with a special bed on the chassis was used to transport the Sno-Cat in the valleys below the snow line. The Sno-Cat traveled 331 miles between February 12 and February 29, 1948 over light sandy snow up to elevations of 9000 feet. The Sno-Cat averaged 5.1 Mi./gal. Gasoline and the repair costs were $10.70. The Dodge Power Wagon averaged 8 Mi./gal. Gasoline over roads considerably snow-blocked. Snow-Catting was difficult where snow lacked cohesion. Wider and longer front skis are recommended to increase the bearing surface.Discussion by Fred Paget.
Keywords: Oversnow vehicles, Tests

1947 Title, Contents, and Minutes (15th Annual Western Snow Conference, 1947)

Runoff from rain and snow - Piper, A.M. (15th Annual Western Interstate Snow Survey Conference, 1947)
The basic principles of the idealized hydrologic cycle are reviewed with emphasis on storage and movement of water in the soil. A distinction is made between ground water runoff and overland runoff in terms of storage and lag, expressed as accumulated deviations from uniform flow over a period of several years. These functions are presented for the period 1920 through 1945 for three rivers in central Oregon: John Day, Deschutes and Metolius, which exemplify minimum, moderate, and maximum effects of storage lag. The Metolius river is shown to have extremely small fluctuations in discharge from year to year, ascribed to a great portion of its flow being derived from ground water runoff; and its response to fluctuations in annual precipitation lags behind that of the John Day River by about five years. Specific techniques and measures for improving seasonal water supply forecasts are suggested.In discussion Mr. E.N. Peterson emphasizes the importance of more accurate and dependable water supply forecasting to the power development agencies and companies in the future.
Keywords: Electric power, Hydrology groundwater

The influence of forest cover on snow melt - Wilm, H.G. (15th Annual Western Interstate Snow Survey Conference, 1947)
There is presented a survey of important literature on the effect of forest cover on snow-melt, with recent results of investigations in the Fraser Experimental forest near Fraser, Colorado. It is shown that forest management, by selective cutting , influences greatly the accumulation and retention of snow on the ground. The evidence supports Dr. J.E. Church's Fir forest, possessing a maximum number of glades, as the most desirable type of snow conservation.Discussion by Walter U. Garstka points out the fact that forest management and watershed management must walk hand-in-hand to secure the optimum of water supplies, timing of runoff and timber products supplies, wood, lumber, paper, livestock grazing, power, flood control and irrigation.
Keywords: Snowmelt research, Watershed management

Snow layer density changes - Work, R.A. (15th Annual Western Interstate Snow Survey Conference, 1947)
A 25-ft. square area of snowpack near Crater Lake, Oregon was studied systematically during the 1940-41 season. By successive excavation and refilling of portions of the study site, and by means of identifying ribbons, the metamorphosis of each layer of the snowpack was observed at regular intervals during the accumulation and melting season. Observations and conclusions are given regarding changes in density, mass or water equivalent, water storage, water transmission characteristics, and melting rates of the snow. Many results confirm existing knowledge and belief of a quantitative basis, others add to or modify well established opinions. An example is the lack of relationship between the density of snow layers and the weight of the overlying snow.Discussion is presented by Forest L. Rhodes of the Corps of Army Engineers, San Francisco, California.
Keywords: Snow research, Snowpack density

1946 Title, Contents, and Minutes (14th Annual Western Snow Conference, 1946)
Records of Sacramento dinner meeting held February 27, 1946

The Army Weasel on Snow Survey Work - Allison, J.M. (14th Annual Western Snow Conference, 1946)
abstract here ...

Snow survey versus winter precipitation for forecasting runoff of the Tuolumne River, California - Boardman, H.P. (14th Annual Western Interstate Snow Survey Conference, 1946)
The relative accuracy of snow survey and winter precipitation data as applied to forecasting the spring and summer runoff of a typical Sierra Nevada western-slope river was investigated. Fifteen years of snow survey data were available, and the same period of precipitation records were used in the comparison. It was obvious on examination of the graphs that several years (4 in the case of snow survey and 3 in the case of precipitation) were much out of harmony with all other years. Justification for these discrepancies was found; they were usually caused by abnormal fall or spring precipitation. These years with abnormal precipitation were omitted in determining the position of the line on the graph showing the relationship of winter precipitation on the water equivalent of snow to stream flow. The conclusion is in favor on snow survey data.
Keywords: Snow surveys, Water supply forecasting

Letter Re: Snow Transportation M-7Snow Tractor - Codd, A.R. (14th Annual Western Snow Conference, 1946)
abstract here ...

Seasonal storage precipitation gages - Codd, A.R. (14th Annual Western Interstate Snow Survey Conference, 1946)
A non-recording winter storage precipitation gage used successfully in a region of heavy snowfall is described. The gage is conical in shape with a standard 8-inch diameter orifice and is charged with a CaCl2 solution of 34% by weight, and covered with a film of light oil. The gage is mounted in a steel tower constructed of 5 ft. sections to exceed the deepest snow depth by at least 5 feet. The gage has a capacity of 300 inches of precipitation. The bottom 100 inches is taken up with the CaCl2 antifreeze solution leaving 200 inches for snowfall and rainfall in the form of added water. The gages are calibrated for stick measurement and also fitted with the necessary valves and safety plugs for draining the solution for weighing at the end of the precipitation season. The antifreeze solution is weighed into the gage and measured by stick depth and then the diluted solution is stick measured and weighed out of the gage. The difference in total weights is compared with the difference of stick measurements by calibration.
Keywords: Precipitation gages, Shielded storage gages

Value of midwinter snow surveys - Criddle, W.D. (14th Annual Western Interstate Snow Survey Conference, 1946)
The forecasting of the seasonal volume of runoff by means of snow survey data made early in the year, before April 1, is discussed. The use of midwinter snow surveys is exemplified from records of a few western streams, and the results are compared with forecasts based on April 1 snow surveys. The results indicate that a forecast based on the maximum value of the snowpack, whenever it occurs, may be superior to a forecast based on the value observed on the same time each year. Reference is made to WSC Paper No. 176-44.
Keywords: Midwinter data, Water supply forecasting

Low-cost storage-type precipitation gages - Fittinger, H.J. (14th Annual Western Interstate Snow Survey Conference, 1946)
A different design of a storage precipitation gage is described and pictured. The gage is designed primarily for low altitude where freezing is not a problem. However, an initial charge of antifreeze solution could be used during winter months to insure against freezing and loss of the catch. Where rain gages cannot be attended in isolated locations this design appears to be adequate.Discussion of the gage design is presented by Ashton R. Codd.
Keywords: Precipitation gage, Shielded storage gage

Snow-Plane Operation in Upper Snake Watershed - Marr, J.C. (14th Annual Western Snow Conference, 1946)
Abstract here ...

The Montana "Sno-Bug" - Monson, O.W.; Stutter, W.J. (14th Annual Western Snow Conference, 1946)
abstract here ...

The Snoplane in Jackson's Hole - Simmons, G.H. (14th Annual Western Snow Conference, 1946)
Abstract here ...

Forecasting Colorado River flow - Stanley, J.W.; Kennedy, R.E. (14th Annual Western Interstate Snow Survey Conference, 1946)
Water supply forecasting procedures used by the U.S. Bureau of reclamation office at Boulder City, Nevada, for estimating the inflow to Lake Mead are outlined. Some of the results and examples of multiple correlation of runoff from the Upper Colorado with snow surveys and precipitation data are presented. There is discussion of forecasts to be made on various dates for various periods of the mass curve adjustments of precipitation records, of the optimum number of stations for multiple correlation, of methods for estimating missing records, and of other factors influencing the precipitation runoff relationship. One of the conclusions of the study is the need for a long period of record in estimating a reliable system for forecasting.
Keywords: Using precipitation data, Using snow survey data, Water supply forecasting

Tucker Sno-Cat - Tucker, M. (14th Annual Western Snow Conference, 1946)
Abstract here . . .

Western Snow Conference Meeting - WSC (14th Annual Western Snow Conference, 1946)
Records of the Sacramento Dinner Meeting, February 27, 1946

Research committee on snow, Western Snow Conference 1945 - Church, J.E. (13th Annual Western Interstate Snow Survey Conference, 1945)
Reports of several member authors are presented. The teeth on snow sampler cutters have been reduced in number and lengthened to avoid packing and freezing of ice in the cutter. Sampler tubes, particularly those of aluminum tend to stick in frozen snow. This difficulty has been largely overcome by shellacking, swabbing with kerosene, and the application of ski wax. Iron pipes of 3 inch diameter set in concrete are excellent snow course markers. Storage gages and recording gages with CaCl2 and protected with wind shields and a film of light oil, have been satisfactory during the 1944 - 1945 snow season. Snow melt day lasts only 6 to 8 hours during April and May at Donner Summit, California. Examples of snow surveys , streamflow forecasts and actual runoff are given as a check on forecast accuracy.
Keywords: Snow research, Snow surveying equipment, Water supply forecasting accuracy, Water supply forecasting procedures

Some factors that influence the accuracy of water supply forecasting in the intermountain region - Croft, A.R. (13th Annual Western Interstate Snow Survey Conference, 1945)
Data on precipitation, accumulation and ablation of snow and year long soil moisture records are presented in relation with streamflow from north and south slopes of small drainage basins in the Wasatch Mts. of Utah. The following reasons suggest that the water content of the snow on April 1 may not be a reliable index of water yield in this area; The water content of the soil mantle, which must be raised to field moistures capacity, before water is available for streamflow, varies on April 1 from year to year. The moisture deficit in the mantle may be partly overcome by rainfall before snow begins to accumulate, thus making more of the snowpack water available for streamflow, especially from the South slopes. Spring rainfall (inch for inch) is more effective in generating streamflow than equal amounts of fall storms. Rapid melting of the snow results in greater water yield than slow melting. The data suggests that further study is desired for the location of snow courses.
Keywords: Snowmelt runoff, Soil moisture research

The dynamics of liquid water in deep snowpacks - Gerdel, R.W. (13th Annual Western Interstate Snow Survey Conference, 1945)
Any solution of the snow melt problem which will improve the forecasting of floods as well as forecasting of agricultural and industrial water supplies is dependent upon a knowledge of the hydromechanics and dynamic potentials which influence the retention and discharge of water by the snowmantle. As a result of studies made of the dynamics of free water in the snowpack at the Central Sierra Snow Laboratory, conclusions are drawn on the melting process of the snowpack. Thermodynamic phenomena associated with the melting or metamorphosis of the snowpack are also discussed, together with techniques of measuring the factors associated with these phenomena. Data are tabulated and graphical representation show relations of factors involved.
Keywords: Snow quality, Snowmelt runoff

Simplified plotting of statistical observations - Gumbel, E.L. (13th Annual Western Interstate Snow Survey Conference, 1945)
A procedure is presented to show that the MEAN number depends, in general, upon the nature of the variate. In order to analyze this postulate consideration was given to the largest observation in a sample of size and ask: What is the mean number of observations such that this value or larger one, happens once again? This question is important for statistical variates as earthquake magnitudes, precipitation, floods, temperatures, and pressures, where the largest value involves specific dangers. Similar problems arise in quality control and in gunnery. However, for a wide class of statistical distributions, it converges toward the sample size. The general solution given in the first section will be applied, in the second section, to some interesting distributions, in the last section it will by used to simplify the plotting procedure advocated in a previous article. (See No. 6 of references)
Keywords: Statistical analysis sample size

Infiltration and runoff during the snow melting season, with forest cover - Horton, R.E. (13th Annual Western Interstate Snow Survey Conference, 1945)
This paper presents a new method of analysis of rainfall and runoff data which permits surface runoff and ground water flow to be segregated and infiltration capacity determined during stream rise. The method is equally applicable to areas with and without snow cover. The determination of infiltration capacity during the snow melt period is, however, the most difficult problem and the method is here applied to this case, using data for areas in the Allegheny Experimental Forest, with varying degrees of forest cover density. For these areas the rate of snow melt per degree-day of temperature excess above 32 degrees F decreased as the cover density increased. During snow melt, infiltration took place at rates governed by the rate of supply of rain and melt water, averaging for the entire snow melting period one-third to one-quarter of the infiltration capacity of the soil. The infiltration capacity under snow cover with unfrozen soils was found to be about 0.05 inches per hour of 1.20 inches per day.
Keywords: Flow separation, Groundwater, Surface runoff

A new forecasting curve for the Kaweah River in California - Paget, F.H. (13th Annual Western Interstate Snow Survey Conference, 1945)
The April through July runoff volume of the Kaweah River at Three Rivers as a function of water equivalent of snow on the ground April 1, spring precipitation, and soil moisture deficiency in the fall is presented. The imperical relation obtained from 15 years of record has a maximum error of less than ten percent. The novel feature of the soil moisture deficiency factor is that it is determined by fall precipitation prior to the accumulation of continuous snow cover at a particular station.Discussion by W.B. Langbein indicates that the application of statistical methods produces a procedure of measuring the effect of the independent variables and permits a more efficient choice and use of the most effective values. Methods are illustrated and discussed.
Keywords: Soil moisture, Water supply forecasting

Mechanized transportation for snow surveying - Work, R.A. (13th Annual Western Interstate Snow Survey Conference, 1945)
A series of field tests of a 4-passenger snow vehicle are described. The machine is supported in the rear by 2 pontoons equipped with endless open-link tracks. Support in front is provided by 2 connected hickory skies. Small pneumatic tires lift the skis from bare ground when required. The front skis are attached to a steering yoke that will rotate over about 30 degrees from the horizontal so that the skis maintain a flat position on the snow. The skis have a 1 inch keel down the center to prevent side slip and aid in steering. A 6-cylinder automobile engine with transmission operates the vehicle at up to top speed of 2 miles per hour. Twelve characteristics to be noted in the performance of over-snow vehicles are listed. This vehicle mentioned met the requirements for performance. (Tucker SnoCat)In discussion R.W. Childreth describes a trial run of an over-snow vehicle developed by the Iron Fireman Manufacturing Company of Portland, Oregon. The trials were made on Mount Hood, in snow conditions difficult for ski travel. Operation details are given.
Keywords: Iron Fireman, Oversnow vehicles, Tucker SnoCat

The use of snow surveys as an aid in flood control operation of reservoirs - Christian, F.G. (12th Annual Western Interstate Snow Survey Conference, 1944)
The hypothetical operation of the proposed Pine Flat Dam on the Kings River, California as outlined by Paget is discussed. Several improvements in the technique of recognizing the start of the decline of runoff are suggested. Some of the methods permit recognition of the start of the decline within 5 days after the peak flow has occurred. (See also SIP 1908 - WSC 154-43)Discussion by L. Standish Hall presents a similar problem on the Mokelumne River in operating the Salt Springs and Pardee Dams. Operational graphs are presented and discussed. Further discussion is presented by R. K. Linsley, suggesting further methods of defining the snow melt hydrograph.
Keywords: Reservoir operation, Snowmelt hydrograph, Snowmelt runoff

Effect of high water table in exaggerating streamflow: 1942-44 Humboldt River Nevada - Church, J.E.; Boardman, H.P. (12th Annual Western Interstate Snow Survey Conference, 1944)
An analysis of the 1942-43-44 seasonal streamflow forecasts in relation to obscure factors that upset the usual forecast accuracy. Considerable more streamflow occurred than forecast by about 120% above the normal flow, when snow survey measurements indicated only 70 to 90% snowpack. The percentage system of forecasting appears to have difficulty in aligning such factors as soil moisture and apparently high ground-water table. Ground-water levels measured in wells did not show a large percentage above normal The preceding fall rainfall and the rainfall during the runoff season were quite high and probably account for the high flows.Discussion is presented by W. G. Hoyt who forwards some analysis of the discrepancy. Reference is made to a previous analysis of the same situation in WSC Paper No. 159-43.
Keywords: Forecast accuracy

The Utah snow-mobile - Clyde, G.D. (12th Annual Western Interstate Snow Survey Conference, 1944)
The two basic principles making the Utah snowmobile successful for transportation over deep snowpack are the split track and the guide runner. The excessive weight of an ordinary tractor was overcome in the Utah Snow-mobile by mounting wide, light metal tracks on the rubber tires of an ordinary automobile. The tracks were wide to reduce the unit load on the snow surface. Snow packing between the tracks and the wheels was overcome by designing a split track with the wheels operating between the two segments of the track. This arrangement provided a self-cleaning device, preventing accumulation of snow between the tracks. Conventional steering tends to overturn the vehicle when one track was stopped. A movable runner, projected in front of the vehicle, operated on fixed swivel at the end of a frame which was rigidly fastened to the chassis. This runner was operated through a cable-chain mechanism fastened to the steering column of the vehicle. Photographs show the mechanical design and features of construction, also transportation over highways. Specifications and performance records are listed.
Keywords: Oversnow vehicles, Utah snowmobile

Post-war management of western forested watershed lands for water yield - Connaughton, C.A.; Wilm, H.G. (12th Annual Western Interstate Snow Survey Conference, 1944)
The need for additional water supplies in the semi-arid western states is indicated in post war demands for expansion of industrial and agricultural facilities. Announcements of large sums for reclamation projects and power production together with flood control and navigation problems. The U. S. Forest Service controlled lands in the mountainous states of the West where 80% of the water supplies originate must be managed through improvements of logging operations, through select cutting to produce a maximum of timber products and water supply with a minimum of soil erosion, silt accumulation and also a prolonged snow melt season, to produce moderate runoff volumes. Proper management of forest lands will increase water yield and improve the forest lands for future production of forest products and water supplies.In discussion Joseph Kittridge emphasizes that watershed management is essential to the economic growth of the western states, through careful conservation planning of the natural resources.
Keywords: Watershed management

Midwinter forecasting of the snow water runoff on years of extremely light or heavy February 1, muntain snow cover - Criddle, W.D.; Marr, J.E. (12th Annual Western Interstate Snow Survey Conference, 1944)
A need is shown to develop a forecasting procedure of seasonal runoff as early as February 1st. A scheme is developed from snow survey data and streamflow for the Snake River and tributaries and also for stations along the Columbia River below the Canadian border. Records from 39 snow survey courses were analyzed in relation to streamfflow records over a series of years where parallel records are available. Although the scheme is feasible, the variability of the occurrence of storms was too uncertain to place much reliability in the procedure. The need for longer periods of records is much in demand for such forecasts. A month to month or day to day procedure could be more efficient.
Keywords: Midwinter data, Water supply forecasting

Snow temperature studies and apparatus at the Soda Springs, California cooperative snow research project - Gerdel, R.W. (12th Annual Western Interstate Snow Survey Conference, 1944)
Errors in the application of glass stemmed mercury thermometers, electrical resistance thermometers (thermohms) thermocouples, and the Bouyoucos liquid resistance thermometers are presented. Heat adsorbed and conducted to the temperature element by the electrical leads is a principal source of error, and was effectively eliminated by fastening the temperature elements to a strand of No. 9 galvanized iron wire suspended between 2 posts 8 feet apart. Subsequently, temperature measurements were made in the snow pack above the soil surface and wires at 1-foot intervals for 12 feet in height. Measurements in the first 10 inches below the snow surface were affected by solar radiation and fluctuation in the ambient air temperature. The data indicated that the soil temperature and the temperature in the snowpack remained approximately 32deg F even though air temperatures of below zero deg F were observed. Photographs of the experimental area and the wires for holding elements are shown.
Keywords: Snow cover thermal effects, Snow temperature

The importance of runoff forecasting to the operation of the Pacific Southwest Power Interchange Committee - Hinson, H.B. (12th Annual Western Interstate Snow Survey Conference, 1944)
The importance of accurate water supply forecasts for use by the Power Interchange Committee towards the production of power on the Pacific Coast is presented. The coordination efforts of the Committee to conserve fuel oil and gas reserves for steam generation in relation to hydro power is one of the aspects of ‘War Time’ economics. The snow hydrologists preparing streamflow forecasts are providing an active service to the wartime economy through power development for industrial use and planning for the routing of power to areas where shortage of power occurs at peak demand periods.
Keywords: Economics of snow surveys, Electric power

Land use and vegetative cover as factors influencing runoff - Kohler, K.O. (12th Annual Western Interstate Snow Survey Conference, 1944)
Watershed analysis is used to estimate the intensity of runoff and watershed yield by considering such factors as slope, topography, sub-surface rock, soil conditions, vegetative cover and land use as physical parameters. Hydrologic factors involved are precipitation intensity, and duration, temperatures, wind movements, snow accumulation. All factors are used towards determination of the most economical land use and watershed yield, towards improving an understanding of better watershed management. Large brush areas present a potential fire hazard and if laid bare cause much soil erosion where the root systems are exposed. Citations of classic examples of watershed damage are included with figures to show economic losses.Discussion is presented by B. A. Madson, U. C. Davis, and N. F. Meadowcroft, federal Power Commission, San Francisco, Calif.
Keywords: Basin analysis, Watershed management

Winter transportation on the high Sierra by sno-motor - Lang, W.A. (12th Annual Western Interstate Snow Survey Conference, 1944)
The ‘Snow-Motor’ owned by the Southern California Edison Company has been driven 956 miles during 245 hours running time. The cost of operation includes gasoline, oil, and repairs, amounts to $1.26 per mile during two years time. The ‘Snow-Motor’ was used to transport 35,000 lbs of 12 gage steel sheets 48 inches x 96 inches in size over deep snow 31 miles from Big Creek to Florence Lake Dam over a 9300 foot elevation summit between April 30 and May 13. A lighter and smaller ‘Snow -Motor’ has been developed. Its outstanding advantage is that the machine can be operated without a sled when necessary. Photographs show the machine in operation with the heavy load pulled on a trailer sled. Specifications and performance records are included in the text.
Keywords: Oversnow vehicles, Sno-motor

Notes on the operation of power driven conveyance for snow: Motor toboggan - Marr, J.C. (12th Annual Western Interstate Snow Survey Conference, 1944)
A ‘Motor-Toboggan’ purchased by the Division of Irrigation, Soil Conservation Service, and the Boise River Board of Control in 1942 has been used for snow surveys during 3 winters. The toboggan operated satisfactorily on reasonably firm cold snow with side grades not exceeding 15%. The engine heated excessively in low gear on sticky and on over-ripe snow. The upkeep has been high. The runners were replaced 3 times in 250 miles of travel. Many repairs and adjustments were necessary. The motor-toboggan is not recommended for use in snow surveying.
Keywords: Motor toboggan, Oversnow vehicles

Comparison of forecasts and actual flows 1942-43 - Paget, Fred (12th Annual Western Interstate Snow Survey Conference, 1944)
Seasonal streamflow forecasts are compared with actual streamflow measurements for the years of 1942 and 1943 are presented in 9 short papers for various areas or states as listed and authors reporting. Text, discussions, and tables showing the comparisons are included. Nevada, Central Sierra East slope H. P. Boardman; Oregon State Streams Wilfred T. Frost; British Columbia, Columbia, Kootenay, Okanagan & Coastal Streams S. H. Frame; Columbia River, United States J. C. Marr, Wayne Criddle; Utah State Streams George D. Clyde; California, San Joaquin & Tributaries W. A. Lang; California, Mokelumne River L. Standish Hall; California, State Streams Fred Paget; Colorado River into Lake Mead J. R. Riter.
Keywords: Forecast accuracy

Basin storage method of developing flood hydrographs from precipitation records - Parsons, W.H. (12th Annual Western Interstate Snow Survey Conference, 1944)
A procedure is advanced for constructing a flood-hydrograph prior to occurrence by analysis of three specific elements or factors that produce the hydrograph. 1) The outflow from surface runoff (snowmelt, rainfall), 2) the outflow from sub-surface storage, 3) the outflow from ground-water storage, and the introduction of a factor named loss characteristics for the particular basin under consideration. Portions of numerous hydrographs of past records are used to set up the cause and effects of the subdivisions of the hydrographs. Rainfall and snow melt enter the problem as snow storage. Graphs are exhibited and explained in the text together with the computed hydrograph and the actual hydrograph superimposed for comparison.
Keywords: Flood hydrograph development

A method for calculating the effect of snow on runoff during rainstorms - Paulson, J.B. (12th Annual Western Interstate Snow Survey Conference, 1944)
The detail procedure for computing the several factors involved in producing the flood hydrograph caused from rain storms and snow melt discussed in WSC Paper No. 162-44 are presented. A formula for calculating the snowmelt runoff portions of the anticipated flood hydrograph is presented and explained. Tables are shown to explain the procedures used for the distribution of rainfall runoff and snow melt during 6 hourly increments of the storm duration. An example of the computation table used in securing the values used in plotting the anticipated flood hydrograph for the storm is included.Discussion of the problem is presented by Ray K. Linsley
Keywords: Flood hydrograph development

A photographic snow survey method of forecasting runoff - Potts, H.L. (12th Annual Western Interstate Snow Survey Conference, 1944)
Photographs were taken of the snow cover on a section of the Continental Divide near Hoosier Pass at the headwaters of the Middle Fork of the Platte River, beginning in the spring of 1934. The same section of each photograph was covered with a transparent template of cross section paper to calculate the percent of the area covered with snow. The data of a 10-year period indicate that predictions of total streamflow can be made from a photograph taken on May 1.
Keywords: Photographic snow cover area, Water supply forecasting

Infiltration and the physics of soil moisture - Sherman, L.K. (12th Annual Western Interstate Snow Survey Conference, 1944)
An analysis of moisture in the soil and the physical explanations of process of infiltration is presented. Examples of data are drawn from USDA Bulletin No. 729, and from well scattered sites over the State of Ohio. Infiltration enters the soil directly through capillary action in all directions and in some cases through gravity channels. This capillary action effects the root zone of plants and is f most interest to the agronomists, while the gravity water, some of which may supply the capillary action, is of most interest to the hydrologist. From this source comes the ground water supplies, and largely soil moisture from precipitation. Infiltration rates are dependent on both. Graphs are exhibited to show effects of capillary absorption and the rate of absorption. Computed data are shown in tables.Discussion by several engineers and soil physicists are included with the references.
Keywords: Infiltration capacity, Soil moisture research

Additional arguments for modification of the national formula for runoff from small agricultural areas - Snyder, C.G. (12th Annual Western Interstate Snow Survey Conference, 1944)
The need for classification of the factors involved in the computation of runoff from small agricultural areas by using an expanded formula, is demonstrated. Factors are, precipitation intensity, soil condition, vegetative cover, infiltration rate together with time of occurrence and duration, with area involved, all must be used to clarify the simple formula without relying on a heavily weighted all covering constant. Tables and graphical examples are use to illustrate the development of flood hydrograph reproduction. The process is discussed by A. F. Pillsbury, J. B. Brown and R. W. Gerdel.
Keywords: Flood hydrograph development, Hydrology, Small watersheds

Difference in basin characteristics as reflected by precipitation runoff relations in San Bernardino and Eastern San Gabriel Mountain drainages - Stafford, H.M.; Troxell, H.C. (12th Annual Western Interstate Snow Survey Conference, 1944)
A procedure is presented to show the relation of precipitation to runoff. When the relations are completed for one particular basin and characteristics of that basin are known, these relations cannot be use or applied to another basin. Each basin appears to be a law unto itself, although procedures can be duplicated. The relations and characteristics are found to be significantly different. In this study, five basins in the San Bernardino and San Gabriel mountains of Southern California are analyzed. Data are shown and the various factors are described in the text. Graphical representations are included to show the relationships.Discussions are included by R. L. Wing and C. B. Meyer.
Keywords: Basin characteristics, Precipitation-runoff

Soil moisture records from burned and unburned plots in certain grazing areas of California - Veihmeyer, F.J.; Johnston, C.N. (12th Annual Western Interstate Snow Survey Conference, 1944)
A detailed study is presented, relative to soil moisture occurrences and disappearances in the root zone of the soil mantle, representing differing soil conditions and soil types an climate conditions. Attempts at revitalization of soil moisture for plant use are discussed. Plant-transpiration is studied under various conditions. These experiments show that plant-transpiration is the chief means by which moisture is lost from the soil, and direct evaporation is a minor cause of water loss and only from the surface few inches. Experimental plots are pictured and described. Data are plotted on graphs to show trends of soil moisture.Discussion by P. B. Rowe and Henry W. Anderson relative to soil moisture studies performed by the U.S. Forest Service Expt. Sta., Berkeley. The 18 references listed indicate that considerable research work has been carried on relative to the problem of soil moisture.
Keywords: Soil moisture research

The effect of timber cutting in a lodgepole pine forest on the storage and melting of snow - Wilm, H.G. (12th Annual Western Interstate Snow Survey Conference, 1944)
Experiments conducted in mature forest of lodgepole pine at Rocky Mountain Forest & Range Experiment Station in Colorado, show that planned cutting will increase the snow cover during the accumulation period. A total of 17.5 inches of water passed through the forest canopy on heavily cut-over plots, as compared with 13.33 inches in the un-cut forest. The accelerated melting rates of the cut-over plots were compensated by the excess snow stored initially. All experimental plots became bare at approximately the same time. Cutting is not advised in areas where floods and erosion are problems. (See also SIP U1839)
Keywords: Forest management optimum water yield, Forest management timber cutting, Snowmelt

Adjusting forecast curves for abnormal spring and summer temperatures - Work, R.A. (12th Annual Western Interstate Snow Survey Conference, 1944)
Factors affecting the snow and runoff relationship are listed, and a method presented for adjusting snow survey results of April 1 in constructing the forecast curve so as to compensate for temperature deviation from normal during the runoff season. The method is based on results of studies on two small drainage basins in Oregon. The selection of 2-month period of temperature departures as well as the correction coefficient to be applied are selected on the basis of the amount of water stored in the snow on April 1 as measured by snow survey . Results of the corrections as applied to both basins are tabulated and graphed for several years.Discussions are presented by Fred H. Paget, Harry Olsen, Ray K. Linsley, and Garfield Stubblefield.
Keywords: Spring temperature modifications, Water supply forecasting

A lateral snow sampler - Work, R.A.; Childreth, R.W.; Frost, W.T. (12th Annual Western Interstate Snow Survey Conference, 1944)
The sections of duraluminum snow sampler tubing were screwed together. A strip of cold-rolled steel 1/16 X 1/2 inch moved freely through guides supported on the inside of the tubing. The slide bar was permanently bent at the cutter end so that it would lay flat against the tubing when driving but would curve inward when pushed towards the cutter end. The tube was then rotated one turn to cut the core free from the vertical face of the hole face. The tube and core withdrawn and weighted to obtain the snow water equivalent of the driver and by noting the length of drive it was possible to compute the density of the snow in the horizontal section. The sampler with this modification cut the retained core within 05% of the sampler drive.
Keywords: Snow sampler lateral sampler

A steel pipe climber - Work, R.A.; Childreth, R.W. (12th Annual Western Interstate Snow Survey Conference, 1944)
The painting of steel pipe snow survey course marker posts presents a problem when the pipes are set in concrete and 20 feet tall. An ingenious device is described and shown in detail drawing and photographs. The climber is used by slipping the feet into stirrups, grasping the pipe above the head, pull both feet up. When down pressure is exerted in the stirrups, lugs are pressed against the pipe and another step up can be made. Climb to the top of the pipe, replace the sign marker and start painting down.Discussion by Fred Paget recommends a light weight extension ladder for this purpose. Photographs of this procedure are pictured. Ashton Codd suggests to forget the stripes, and use a brush attached to long extension aluminum rod, and paint the pipe one solid color: like danger orange.
Keywords: Equipment snow survey, Snow survey course maintenance

1943 Title, Contents, and Minutes (11th Annual Western Interstate Snow Survey Conference, 1943)

Prediction of temperature-distribution in frozen soils - Berggren, W.P. (11th Annual Western Interstate Snow Survey Conference, 1943)
The problem of frost penetration in moist soils is idealized as a problem of heat conduction in a semi-infinite slab of porous material through which a liquid is uniformly diffused. Solution of the heat equation with selected boundary conditions suggests that the depth of the frozen layer increases with the square root of time. Formula development from laboratory data are exhibited. The difficulties in attacking this problem of varying properties of soil classification, and varying quantities of soil moisture and distribution are admitted by the author.Discussions are presented by Dr. J.E. Church and Dr. Robert E. Horton.
Keywords: Frost penetration

Hydrology's part in the war effort - Bernard, M.l (11th Annual Western Interstate Snow Survey Conference, 1943)
Hydrologic planning is proven to be an indispensable part of expanding industry and agricultural production demands even with drought conditions to keep pace with the World War II demands. Flood control works are hurriedly constructed and flood warning systems are increased with more attention given to the forecasts and warnings. Ground water supplies are mapped and potential uses for increased demands on municipal and agricultural demands. Hydrologists are consulted for air-field construction, snow removal and data necessary to support the military installations. The importance of consistent hydrologic records through war and peace is a means of being able to meet the demands of hydrologists nationwide when there is hydrologic planning to be done by the construction engineers and others.
Keywords: Hydrology planning, Wartime effort

Snow study program at Soda Springs near Donner Summit of Central Sierra Nevada - Church, J.E. (11th Annual Western Interstate Snow Survey Conference, 1943)
The efficiency of precipitation gages and snow surveying, the physics of snow, temperature in snow, and changes in snow texture were studied at Soda Springs, California, during 1942-43. Ten precipitation gages were used in the test. It was found that unshielded gages showed considerable catch deficiency. The use of oil in the cans has reduced the evaporation in shielded gages almost to zero. The weight beam of the Stevens Type-W recording gage was sensitive enough to respond to footsteps on the platform and the opening and closing of the door. A heavier oil was used the damping cup to correct the condition. The movement of moisture in snow was determined by using dyes, of which Fuschine had all the requirements. Calorimetric measurements of snow were made and the results tabulated. Snow was found to crust at 34degF. The melting day lasted 6 hours in early spring at 7000 ft. altitude. Resistance thermometers were used to measure snow and soil temperatures. The layout of the experiment are shown in drawings and photographs, also instruments. Results of the data collected are discussed in the text.
Keywords: Precipitation gages, Snow physical properties, Snow research

Three unusual runoff years in the Humboldt Basin, Nevada, 1940-41, 1941-42, and 1942-43 - Church, J.E.; Boardman, H.P. (11th Annual Western Interstate Snow Survey Conference, 1943)
Double normal precipitation from April to June produced an excess of 121,500 acre-feet above the 150,000 acre-feet forecast for the Humboldt River, Nevada during the 1941 runoff season. The forecast for 1942 based solely on snow cover was for 193,200 acre-feet, actual flow was 493,200 acre-feet an excess of 139.8% normal/ The excess flow in 1942 was caused by the high water table resulting from the heavy 1941 and early 1942 rains. Actual flow in 1943 was 200% normal due to high moisture content of the soil. Streamflow caused by high water table is distributed throughout the runoff season.
Keywords: Forecast accuracy

Precipitation-runoff relationships as a basis for water-supply forecasting - Clyde, G.D.; Work, R.A. (11th Annual Western Interstate Snow Survey Conference, 1943)
The early history of snow surveying is reviewed. The surface runoff from a watershed equals the total precipitation minus losses through evaporation, transpiration, leakage, and ground water storage. Factors affecting runoff yield per precipitation unit are time of occurrence and form of precipitation, and temperature. Runoff can be measured by standard methods within 5 to 10% accuracy. Precipitation measurement, however, is difficult and expensive. Water losses, depending on many factors, cannot be quantitatively measured. The best basis yet developed for forecasting is by measuring the accumulated snow cover at representative points (always the same points) and use these data as an index to seasonal runoff. Results can be adjusted for abnormal spring precipitation or temperatures. Procedures for these relationships are shown graphically. Examples of data are tabulated and discussed.Discussion by Ray K. Linsley, Merrill Bernard are included.
Keywords: Graphical procedures, History of snow surveys, Water supply forecasting

A simple procedure for the day-to-day forecasting of runoff from snow melt - Linsley, R.K. (11th Annual Western Interstate Snow Survey Conference, 1943)
Daily runoff from snow melt is based on degree days over a 24-hr period. A degree day is one degree over 32deg F for 24 hours. Mean temperature at one station is used and curves have been drawn relating melt in inches of water to the mean temperature at different altitudes. Another curve relates inches of melt to runoff during each part of the runoff season. The method is almost entirely empirical and neglects several factors. The procedure is applicable in regions developing semi-permanent snowpack during the winter and in basins where extreme elevations restrict melting at any instant to a limited portion of the snow cover.Discussion is included by R.A. Work.
Keywords: Short term forecasting, Snowmelt and runoff, Water supply forecasting

Some accomplishments in snow-surveying - McLauglin, W.W. (11th Annual Western Interstate Snow Survey Conference, 1943)
A resume of snow survey activities in the Western United States indicating considerable progress with cooperative phase of the program with Federal-State-Private agencies and companies through contributions of manpower and finances. The present network comprises 829 dependable snow survey courses with an average of 15 samples per course. There are 177 cooperators measuring a courses 3 times per season and some 5 times. During the 1943 season 966 individuals took part in the field work. Water supply forecasting procedures have improved with more and better data and accuracy has gradually become more dependable. Requests for advanced information of the probable size of streamflow for irrigation has been coming from financial concerns, eastern wholesale producers, canning companies, power companies, and agricultural interests. A great deal of interest is being show in the research of the physics of snow, and finances for such work is being sought.Discussion by George H. Canfield and R.A. Work.
Keywords: Snow survey cooperative program

Improving stream-flow predictions by the use of past records - Niederhof, C.H. (11th Annual Western Interstate Snow Survey Conference, 1943)
Snow survey courses and precipitation stations were established in the Great Basin of western Newfoundland as early as 1928. the need for this network of hydrologic stations was to create records to be used in forecasting the probable water supply for a hydroelectric power development used to operate a paper mill at Corner Brook, Newfoundland. Results of the forecast scheme, from 1926 to 1935 were consistently LESS than actual flows. A corrective procedure is presented by using graphical and statistical methods to correct the minus errors with actual forecast volumes and thereby correct the errors to a more dependable figure. Data are exhibited in tables and the graphical solution with statistical methods are shown and discussed.Discussion by Fred Paget points out the need for such procedures to find the causes for consistent minus or plus forecasts being caused from some unmeasured hydrologic factors. Paget also refers to similar procedures discussed in WSC paper No. 44-38, and Elges WSC paper No. 64-39.
Keywords: Electric power, Snow surveys, Water supply forecasting

Forecasting runoff for power and irrigation from relatively low-level areas - Olsen, H.; Price, E.B. (11th Annual Western Interstate Snow Survey Conference, 1943)
A forecasting procedure is developed for estimating the forthcoming water supply from the 2,205,000 acre Klamath River Basin in Eastern Oregon. Two thirds of this basin lays in the rainfall altitudes while one third lies at high elevations with snow cover during the winter. The basin is divided into 6 smaller tributaries and handled separately. Where areas are covered with snow this source of supply is forecast with data from snow surveys while the rainfall portions of the basins are forecast with rainfall formulas. The data for these procedures are shown in computation tables, where the factors are weighted for areas and constants for either rain or snow portions. The separate forecast scheme is routed downstream building a total forecast into Klamath Lake. The weighting factors and the procedures are explained in the text.Discussions are presented by Dr. J.E. Church, Bertram S. Barnes, and R.A. Work.
Keywords: Precipitation data, Water supply forecasting

The use of snow-surveys as an aid in flood-control operation of reservoirs - Paget, F.H. (11th Annual Western Interstate Snow Survey Conference, 1943)
Two types of floods occur on the Sierra tributaries of the San Joaquin River: winter floods from heavy rains, and late spring floods from melting snow. Snow survey data as of April 1 have provided a reasonable accurate forecast of total April through July streamflow. Snow melt floods can be predicted at least a week in advance from snow pack daily temperature data. A hypothetical operation of the proposed Pine Flat Dam is outlined on a policy adopted for the control of rain floods and water conservation aimed to have a full reservoir at the end of the snow runoff period.Tables and graphs illustrate the procedures.Discussions by James E. Jones and H.P. Boardman present agreement in the procedures described and present other factors for consideration for increased accuracy in reservoir operations.
Keywords: Reservoir operation, Water supply forecasting

Hydrology's part in the war effort - Stevens, J.C. (11th Annual Western Interstate Snow Survey Conference, 1943)
An expose of the tremendous speed of war time construction of military cantonments and industrial expansion without adequate hydrologic planning is aired. Large sums of money were wasted hunting for water supplies where none existed within reasonable limits. No studies were made of surface supplies or groundwater supplies. Many cases of poor drainage systems with no lower ground to construct them, or the possibility of flood damage to buildings or life. Other cases of industrial expansion of plants and cities into well known flood plains along the large rivers. Little thought was given to previous records of flood damage or heights. Hydrologic planning is an essential part of all expansion and construction.
Keywords: Hydrology planning, Wartime effort

Stream-flow forecasting by pattern-behavior - Wahle, R.H. (11th Annual Western Interstate Snow Survey Conference, 1943)
An exhaustive study of streamflow hydrographs plotted of data gathered at Cascade Locks on the Columbia River, covering the period 1886 through 1942. In the first phase of the work the graphs are classified according to type, magnitude and timing of the first 6 months of flow of the water-year, peak flow is also tabulated, and used in the ensuing forecast procedure. The second phase consists of consulting the current records to fix the probable classification, and characteristics of the current year. The third phase consists of a search for a similar year that closely matches the present year up to the time of forecasting. Several examples of the pattern forecast are shown and discussed with forecast accuracy shown. Conclusions are drawn that the procedure works well on very large drainage basins where a great variety of weather conditions are involved. The scheme may not work as well on tributary basins with relatively small areas and also a short period of records.
Keywords: Runoff pattern analysis, Water supply forecasting

Soil-moisture under a coniferous forest - Wilm, H.G. (11th Annual Western Interstate Snow Survey Conference, 1943)
On the Fraser Experimental Forest, Colorado, a detailed experiment is being conducted to find out the effects of cutting mature lodgepole pine on various factors affecting water yield. Of these factors, soil moisture deficiencies are particularly graphic in showing the relative consumption of water by uncut and cut-over stands. One year’s data have been collected on soil moisture deficiencies; although the study will require several more years for completion, the methods and results are of sufficient utility to be worth current discussion. The experimental design and sampling procedures are discussed. Analysis of the first year records are shown along with text discussion of results and probable refinements to be made when further years of records are available.
Keywords: Forest land, Soil moisture, Water yield

Winter transportation in the high Sierras by Sno-Motor - Ducker, P.H. (10th Annual Western Interstate Snow Survey Conference, 1942)
The description and use of the Sno-Motor, for winter transportation to reservoirs in the High Sierra of Calif. are presented. The Sno-Motor has one 56-inch endless-type crawler tread assembly running completely around the vehicle. It operates similarly to a caterpillar tractor. The vehicle can negotiate a 50% slope and carry a 2.5 ton load. The engine, transmission-and drive mechanism, fuel tank and radiator are mounted on the bottom plate of the tractor to provide a low center of gravity and excellent stability for hillside travel. It exerts a weight of 170 lb/sq.ft. on the snow and has a speed ranging from 0.5 - 20 mph. Its 50 gallon gasoline tank provides enough fuel for 12 hours of operation. All the mechanism is housed within the oval shaped pontoon, operators cab is mounted over the rear.
Keywords: Transportation oversnow vehicle

Detachable lashings for ski safety - Herz, W.J. (10th Annual Western Interstate Snow Survey Conference, 1942)
A description of a Safety Ski Binding is presented. It is recommended that safety bindings be used for all cross country travel to prevent wrenched knee muscles and broken legs. The name of the manufacturer is included.(See also TAGU 1942 Part II pg. 417-418 for pictures and further description.)
Keywords: Safety ski bindings

Comparison of forecasts and actual results, 1941 - Paget, F.H. (10th Annual Western Interstate Snow Survey Conference, 1942)
A round table discussion of water supply forecasts made in 1941 is presented in 5 short papers. Forecast volumes are compared with actual streamflow figures as indicated in the several tables, for the sections of the Western States involved:California, 26 Central Valley Streams Fred H. Paget; California, Mokelumne River Watershed L. Standish Hall; California, Upper San Joaquin River William A. Lang; Nevada, Central Sierra, East Slope H.P. Boardman; Nevada, Humboldt River Basin Dr. J.E. Church; British Columbia, Canada Columbia River Kootenay River, Okanogan River S.H. Frame.
Keywords: Forecast accuracy

Soil freezing and forest cover - Belotelkin, K.T. (9th Annual Western Interstate Snow Survey Conference, 1941)
The depth and time of soil freezing and the rapidity of thawing are related to type of forest cover, effect of snow cover, forest litter, natural internal soil drainage, and soil texture. (Item 1292 Bibl. prepared by Purdue Univ.) Data were collected from plots laid out at the Gale River Experimental Forest in northern New Hampshire. Three seasons of data are available for plotting of graphs showing the three seasons of data. No definite conclusions are drawn.In discussion Dr. J.E. Church relates some of his observations. Paul L. Bean lists 7 conditions for frost in the ground and relates data and studies carried on in New Hampshire and Maine. Walter T. Wilson relates studies of frost penetration to freezing of water pipes in Wisconsin.
Keywords: Frost penetration in forests, Frost penetration in soils

A new technique for the deterination of heat necessary to melt snow - Bernard, M.l; Wilson, W.T. (9th Annual Western Interstate Snow Survey Conference, 1941)
A quantitative determination of the heat of melting of snow was devised by the U.S. Weather Bureau. A snow sample is added to a measured quantity of hot water of known temperature in a calorimeter. The difference between initial volumes of water indicates the amount of snow in the sample. The temperature difference shows the amount of heat necessary to melt the snow. A ratio of the heat of melting, in cal/gr to the 80 cal/gr of latent heat of fusion, is designated as quality of snow. Observations indicate a wide variation in snow quality. Coarse grainy snow has a minimum quality of 70-80%; new snow, of fine particle size, has qualities of less than 50%. Tables include data from experiments conducted in New York State. Photos illustrate a field sampling kit for snow quality measurements.
Keywords: Calorimetry, Snow quality, Snowpack physics

Progress toward a rational program of snow melt forecasting - Bernard, M.l (9th Annual Western Interstate Snow Survey Conference, 1941)
The problem of utilizing the natural storage of water by snow fields is compared to artificial storage by dams. The amount of water available must be determined and the rate of release or withdrawal must be evaluated. Observational facilities should be provided to determine the amount of water in the snow pack and to study the melting processes. heat transfer by convection and radiation between the snow surface and the overlying atmosphere is considered an important factor. An organization chart for future research studies is exhibited.
Keywords: Snow melt research

An improved escapment for recorder clocks - Better, F. (9th Annual Western Interstate Snow Survey Conference, 1941)
An improved escapement for recording clocks is described and pictured. This piece of intricate equipment is designed for field replacement by the hydrographer when visiting stream or other measuring devices in remote places. The new escapement is mounted on a solid brass plate to insert in the standard clocks. On this plate is mounted the balance wheel with the Elinvar hair spring and its regulating lever, the double roller and shaft and escapement shaft. The base plate is keyed into position and held in place by counter sunk oil reservoirs; all built to precision of fine watch making. The unit is packaged in a small dust proof case. They will run for 2 years without cleaning.
Keywords: Recorder clock escapements

The duraluminum snow sampler under strain: A discussion - Church, P.E.; Church, J.E. (9th Annual Western Interstate Snow Survey Conference, 1941)
Three weaknesses were observed in a duraluminum snow sampler during a field test. Teeth from the cutter bit broke when the sampler met a 4 inch crust of ice down in the snowpack. The sleeves on the end of the sections of the sampler turned in attempting to drive the sampler through the ice crust. The spanner wrenches failed to hold when attempt was made to unscrew the sections after sampling. Changes in the duraluminum snow sampler to remedy these defects are recommended.
Keywords: Snow sampler design problems

Type curves and variability of annual snowfall: State of Washington - Church, P.E. (9th Annual Western Interstate Snow Survey Conference, 1941)
Graphs of average snow depth against months, for over 100 locations in the State of Washington were drawn from data taken over a period of 23 years. The graphs were sorted into groups according to characteristics such as shape of curve, continuity of snow cover, maximum depths, etc. The curves fell into 7 main groups, O-, D-, P-, M-, J-, F-, S-. It was found that types were logically distributed topographically. Polar Pacific air is a dominant factor on snow cover west of the Cascades. Altitude, position with respect to mountains, and influence of polar air masses are other factors affecting snowfall and snow cover in the State. The standard deviation and the coefficient of variation for 107 stations are tabulated and indicate a variation with the type of snow.
Keywords: Snow cover distribution

Whither snow surveys? - Conkling, H. (9th Annual Western Interstate Snow Survey Conference, 1941)
A history of the Snow Survey Program in the State of California is presented. Details of the early cooperation with Dr. J.E. Church back in 1917 and progress of this work until a final beginning of a California State Cooperative Snow Survey Program in 1929, under the leadership of Harlowe M. Stafford. The establishment of snow survey courses in most of the major stream drainage basins was started and supplemented with precipitation stations in the lower altitudes, the collection of historical records was begun and analysis work for forecasting formulas was started. Fred H. Paget was assigned to this project in 1935. Mention is made of the West Wide Snow Survey and Water Forecast Program started by the Dept. of Agriculture in 1935.Dr. J.E. Church in discussion lists the formation of Snow Survey Programs throughout the United States, chronologically beginning with Charles E. Mixer in 1900 through 1938.
Keywords: History snow surveys

Cleaning and shellacking sampler tubes by immersion - Cowgill, P.S. (9th Annual Western Interstate Snow Survey Conference, 1941)
Shellac coating can be removed from duraluminum snow sampler tubes by immersing in a tank of commercial denatured alcohol. The dipping tank recommended is 4 inch in diameter and 36 inches long, with a flat steel plate welded at the base. A tube with 2 or 3 coats of shellac will be cleaned in about 20 minutes; 8 to 10 coats requires 45-60 minutes for thorough shellac removal. The dipping tank can be used for shellacking snow sampler tubes by immersing in shellac diluted 4 parts of shellac to 1 part denatured alcohol.
Keywords: SNow sampler maintenance

A new design for a canvas case to carry snow survey tubes and accessories - Cowgill, P.S.; Elges, C. (9th Annual Western Interstate Snow Survey Conference, 1941)
A carrying case to carry balance, tape, sampler tubes, cleaning hook, etc., has been designed in 2 units. The second section, can be detached and left if exceptionally long sampler will not be needed. Wide web shoulder straps make for easy carrying and a belt holds the pack in position, and keeps the case from flying over the head in a bad fall, a safety feature.
Keywords: Snow sampler carrying case

A review of Chatillon and Sons' latest spring balance for the Mount Rose Sampler - Cowgill, P.S. (9th Annual Western Interstate Snow Survey Conference, 1941)
A new spring balance for the Mount Rose snow sampler improved compactness, readability, weight, and accuracy. The dial range reads from 1 to 100, and the numbers and graduations are plainly visible. Some of the changes recommended to correct defects are: lengthening of the suspension bar, expansion of the zero adjustment to a full turn, strengthening of the framework of the case, finishing the case with a dull surfacing, and providing a balance with a screw which can be turned by a knife.
Keywords: Snow sampler spring balance

Test of snow sampling tubes of large and small diameters - Goodell, B.C.; Roberts, K.L. (9th Annual Western Interstate Snow Survey Conference, 1941)
A Mount Rose type sampler with a cutter of inside diameter 1.485 inches was compared in field tests with a sampler having a cutter with inside diameter of 2.787 inches. The results of 32 samples with each set gave a coefficient of variation of 7.82% for the Mt. Rose sampler and 9.24% for the larger sampler. Additional 15 measurements using the gram scales gave lower values but similar variations. The Mt. Rose type of snow sampler proved more practical and as accurate as the larger sampler, under the conditions of the tests. Comparative data are exhibited in tables.
Keywords: Snow samplers comparison tests

Forecasting the date of the decline of the Carson Rivers on the basis of the seasonal percentages of the contributing snow cover - Krummes, P. (9th Annual Western Interstate Snow Survey Conference, 1941)
Streamflow decline to 200 sec. ft. was predicted as an aid to farmers by comparison with records of previous years during which the April snow cover was approximately the same. The 1939 flow declined to 200 sec. ft., 5 days after the forecast date. The 1940 streamflow was 200 sec. ft., 10 days before the forecast data, probably due to abnormally high May temperatures.In discussion, H.P. Boardman proposes a graphical solution to this problem by using the East Carson River as an example.
Keywords: Water rights, forecast for, Water supply forecasting

Analysis of high rages of snow melting - Light, P. (9th Annual Western Interstate Snow Survey Conference, 1941)
The heat exchange between warm, moist air and the underlying snow surface was found to be influenced chiefly by convection and condensation. These factors were expressed algebraically and combined to yield the effective snow melt. Logarithmic distributions of wind, temperature, and vapor pressure were assumed in developing this equation. Evaluation of constants involved in the turbulent transfer of heat required instruments at two levels in field observation but a single level may be used in connection with the equation for snow melt where reference levers are specified and the roughness parameter is known. The resulting equation then gives snow melt as a function of mean wind velocity, and vapor pressure. Application of this formula to a drainage basin necessitated evaluation of temperature and vapor pressure at different elevations by using conventional linear lapse rates. Corrections also are given for the modifications in the air mass as it moves over a large drainage area. The actual basin snow melt is taken proportional to the theoretical snow melt determined by the equation. The individual constant was evaluated by statistical methods.
Keywords: Snow cover ablation, Snowmelt runoff

Comparison of forecasts and actual results, 1940 - Paget, F.H. (9th Annual Western Interstate Snow Survey Conference, 1941)
A round table discussion of Water Supply Forecasts made in 1940 is presented in 9 short papers. forecast volumes are compared with actual streamflow figures as indicated in the several tables, for the following sections involved:California, Central Valley Streams Fred H. Paget; California, Owens River Basin James E. Jones; California, Huntington Lake, Big Creek W.A. Lang; California, Mokelumme Basin L. Standish Hall; Nevada, Central Sierra, East Slope H.P. Boardman George Devore Leigh L. Stanford; Nevada, Humboldt Basin Carl Elges; Idaho, Upper Columbia, U.S.A. James C. Marr; British Columbia, Kootenay, Okanogan S.H. Frame; Oregon, Oregon Basins R.A. Work J.H. Ryan
Keywords: Forecast accuracy

Correlation of streamflow and snow cover in Colorado - Parshall, R.L. (9th Annual Western Interstate Snow Survey Conference, 1941)
The relation between streamflow and water content of the snowpack is affected by many factors, such as topography, temperature, wind, and soil moisture conditions at freezing. Forecasts based on snow water content have varied as much as 24% from actual flow since 1935. It is assumed that various responsible components can be evaluated within limits and that corrections may be determined to permit an accurate forecast of the seasonal (April - July or Sept.) probable water supply. The photographic method of measuring snow (See WSC 41-37) and relating to streamflow to areas measured by a grid over photos has had promising results. The record is too limited at this time for final conclusions.
Keywords: Snow cover photo analysis, Water supply forecasting

The use of snow survey predictions in the operation of combined flood control and conservation reservoirs for regulation of snowmelt runoff - Showman, A.C. (9th Annual Western Interstate Snow Survey Conference, 1941)
Operation curves for Lake Tahoe (Calif.) are given and discussed. Construction of the curves is based on recorded snowmelt runoff, while their use is based on snow survey predictions of runoff. The hypothetical operation of Lake Tahoe for flood control and conservation, using snowmelt runoff versus release curves, is illustrated. As the season progresses and forecasts are more reliable the plan of operation can always be changed, probably up through late April or on the May first surveys.
Keywords: Reservoir regulation, Snowmelt runoff

An outline of the thermodynamics of snow melt - Wilson, W.T. (9th Annual Western Interstate Snow Survey Conference, 1941)
The heat required to raise the temperature of dry snow is shown to be very small compared to the heat required to convert the snow entirely to liquid water. The various factors involved in the heat transfer processes leading to the melting of a snow cover are explained separately. The solar radiation absorbed may be balanced by irradiation from the snow surface. heat transfer by conduction through the snow to the earth or to the atmosphere is negligible. Heat exchange by convection and condensation exceeds heat transfer by any other means. Evaporation and warm rainwater also are contributing factors. The liquid water content and the density of the snow cover, the melting of frozen ground, the areal distribution of the snow cover, and the air trajectory over the snow must be considered in evaluating the heat transfer processes or forecasting snow melt. A method of estimating the rage and progress of snow melt is applied to a specific example. Formula development and application are included.
Keywords: Snow ablation, Snow melt runoff

The mountain snow survey: Its genesis, exodus and revelation - Alter, J.C. (8th Annual Western Interstate Snow Survey Conference, 1940)
The beginnings and growth of snow survey work is reviewed. A comparison was made of streamflow forecasting from snow survey values and total precipitation measured over a period of 21 years in the Big Cottonwood watershed, near Salt Lake City, Utah. The results indicate an average error of 18.2% using snow survey method and 13.7% using the total precipitation method. It is suggested that stream discharge forecasting is more accurate and efficient with precipitation measurements than snow survey data.
Keywords: Precipitation, Snow surveys, Water supply forecasting

Some factors affecting frost penetration - Atkinson, H.B.; Bay, C.E. (8th Annual Western Interstate Snow Survey Conference, 1940)
The measurements of frost depth were obtained by the use of a King soil tube and hammer. After measuring snow depth the tube was driven into the soil profile gradually. The core samples were removed and examined for ice crystals. The depth at which these crystals occurred was recorded as the frost depth. Some of the factors which have been found to affect frost penetration are snow depth, vegetal cover, atmospheric pressure, exposure, initial soil temperature, moisture content of the soil, soil type, snow density, and organic matter contained in the soil. Graphs are shown at each station and date with the depth of snow and of frost line. The type of ground cover and soil type are shown. The data collected is shown in tabular form. Open discussion comments are included from several engineers.
Keywords: Frost penetration in soils

A quantitative forecast system for power-and flood-warning in the Androscoggin River Basin, Maine - Bean, P.L.; Thomas, P.W. (8th Annual Western Interstate Snow Survey Conference, 1940)
Snow survey techniques in the Androscoggin Valley are described. Comparison of the depth of snow curves with water content of snow curves gives a specific gravity of the snow cover at any given date. These data are used to estimate the ability of the snow cover to absorb rain. The characteristics of the snow cover from day to day as influenced by the temperature are indicated by a set of curves which are utilized in flood estimation. The forecasting of the 1936 flood through snow surveys is described.In discussion, Mr. Phillip W. Thomas emphasizes the Quantitative Forecast System as applied to the power development by the Rumpford Falls Power Co., as well as flood warnings. Illustrated by a key curve of elevation and precipitation data and tables of data on aspect of stations and elevation and snow survey measurements of water content. A location map with contours indicates the area involved.
Keywords: Flood prediction, Power prediction, Water supply forecasts

Snow sampling equipment for granular and crusted snow in New England - Bean, P.W.; Bendtsen, F.A. (8th Annual Western Interstate Snow Survey Conference, 1940)
A system of 50 permanent snow stations was developed in 1937 in the Androscoggin Valley in New Hampshire and Maine for measuring snow cover to predict the rate and amount of spring runoff. Three or four samples of snow are obtained in a snow sampler with a 3-inch inside diameter and a cutter of 2.65 inches diameter. The samples are weighed and the water content recorded. The size and shape of the snow crystals are determined with a microscope. The thickness of the ice on the ground and conditions of ground are recorded. The snow temperature at 10 inches depth is measured. The 50 inch snow sampler used in these tests has been found superior to the Mount Rose Sampler for coarse New England snow.Discussion by Dr. J.E. Church and Kenneth L. Roberts is included.
Keywords: Snow survey network, Snow survey sampling tubes

Progress report on mountain snowfall program of the Weather Bureau - Bernard, M.l; Codd, A.R. (8th Annual Western Interstate Snow Survey Conference, 1940)
Modern stations are equipped with batteries of 3-5 shielded storage precipitation gages. The gages, include shields and support stands, are of all metal construction and may be equipped with a clock mechanism capable of running 30 days without attendance and furnishing a record of precipitation, rain or snowfall. The gages are charged with a solution of calcium chloride with a film of oil to prevent freezing or evaporation. The gage stands may be as high as 20 ft. depending on the probable amount of snow depth at the location. A statistical analysis of the records of 47 stations over a 2 year period indicates that the batteries of gages may be reduced from 5 to 3 without loss of accuracy. A classification of hydrological stations is given and mountain snowfall stations are mapped. Detail construction of the metal stands and shields are show in a sketch.
Keywords: Precipitation gages, Shielded storage gages

A proposed snow survey system for the Yakima basin - Boardman, H.P. (8th Annual Western Interstate Snow Survey Conference, 1940)
The percentage system, normals, and precipitation versus runoff are discussed with reference to snow surveys in the Yakima River Basin, Washington. The analysis considers only the period of 1908-09 - 1936-37 for 5 stations, which though covering but a small part of the complete Yakima basin, are at the headwaters and give a good indication of probabilities farther downstream. The methods of collecting the data are explained and the data are interpreted. Data on precipitation, the relation of precipitation and runoff in percent of normal, and runoff in acre-ft., of the Yakima River at the Cle Elum gage are tabulated. April-July runoff; Dec.-March precipitation; and April-June precipitation are graphed as percent of normal for 1908-09 and 1936-37.
Keywords: Percentage system, Water supply forecasting

Ice crusts and snow settling at Snoqualmie Pass, season of 1939-40 - Church, P.E. (8th Annual Western Interstate Snow Survey Conference, 1940)
Eight trips were made to Snoqualmie Pass, 63 miles east of Seattle, between Dec. 27 and April 4, 1940. Profile cuts were made in the snow, temperatures were taken at various depths, and dye solutions were poured over the snow to test permeability. Snow fall was normal during the 1939-40 winter. Two cold spells occurred and these produced impervious crusts. No important crusts developed after January. A graph of the various crust layers and their movement during the winter and melt season is shown and described in the text.
Keywords: Ice crusts, Snow pack analysis

Map of western snow survey systems - Church, J.E. (8th Annual Western Interstate Snow Survey Conference, 1940)
The map shows location of 20 snow survey systems and forecast quadrangles in the Western United States, and Canada, grouped in 6 snow survey systems. The main areas covered are the Sierra, Columbia, Great Basin, Colorado, Saskatchewan, and Missouri systems.
Keywords: Snow survey networks

The relation of snow to maximum flood peaks: A discussion - Church, J.E. (8th Annual Western Interstate Snow Survey Conference, 1940)
The sources of maximum floods are placed near the snowline rather than in the upper reaches of the watershed where the area is smaller, temperature lower, and the body of snow deeper. The effects of the relative heaviness of the snow-cover on the windward and leeward sides of the mountains, the relation of temperature to snowmelt rates, the effect of rainfall on snow and snow density are factors producing floods. An analysis of temperature, snow on the ground, precipitation and flood peaks was made on four floods in the Tahoe-Truckee Basin during 1907, 1928, 1937 and 1940, and in the Sacramento and Humboldt Basins. Hydrographs of the various flood flows are shown, and included are the various factors involved. Snow data at various elevations in the basins is also included.Several discussions are also included.
Keywords: Flood control prediction, Snow melt floods

Soil moisture studies as an aid in forecasting runoff from snow cover - Clyde, G.D. (8th Annual Western Interstate Snow Survey Conference, 1940)
The determination of soil moisture at the beginning of the accumulatin period and the melt period provides an index of water required to prime the soil in any given year. An improved soil moisture indicating device was developed at the Utah State Agricultural College, to make these determinatins quickly and accurately. The instrument is based on the principle that the capacity between 2 plates separated by a porous ceramic dielectric material depends on the moisture content of the dielectric material. Capacity measurements of a cell which reaches moisture equilibrium with the surrounding soil are converted into moisture percentages of the soil. The cell can be burried undet the heavy snow pack with the lead wires brought up from the cells to a terminal block in a steel pipe, above the depth of the anticipated snow at the station. The soil moisture measurement provides an index for correcting snow cover runoff to compensate for earth mantle losses.
Keywords: Capacitance instrument, Soil moisture measurements

Calcium Chloride solutions in the operation of precipitation gages - Codd, A.R. (8th Annual Western Interstate Snow Survey Conference, 1940)
Freezing test indicate that Calcium Chloride solution is superior to NaCl solution in precipitation gages. The brine is used to melt the snow as it falls into the gage and to prevent damage to the gage by freezing water. A eutectic freezing point of -60deg F results with a solution of about 30% Calcium Chloride by weight. A 23% NaCl solution forms salt crystals at -5deg F and becomes solid at -8deg F. Precipitation gages in which Calcium Chloride is used are usually charged with a 33.4% solution (1 qt. of salt to 1 qt. of water and 4 oz. SAE.10) after 2.5 in. of precipitation has been caught, another quart of salt is added to strengthen the solution. The film of oil prevents evaporation and overcomes the deliquescent effect of the salt. Tests were made of various percentages of strength solutions in a dry-ice chamber. NaCl solutions and a sample of water from the Great Salt Lake turned solid at -8deg F. However, the 33.4% solution of Calcium Chloride began to become slushy like frazil ice at -55de gF, and remained in this semi-liquid solution for two hours at -65deg F. Thus assuring no damage to the gages.
Keywords: Calcium Chloride tests, Storage precipitation gages

Report on snow surveys of 1939 in the Chelan Basin - Collins, E.H. (8th Annual Western Interstate Snow Survey Conference, 1940)
A summary of 9 winters data on depth, density and water content of snow at selected places in the Chelan Basin, Washington, is given in the form of tables and graphs. The data are used to predict levels of Lake Chelan and stream runoff in the area.
Keywords: Graphical analysis, Reservoirs, Water supply forecasting

Research on snow by the Forest Service - Connaughton, C.A. (8th Annual Western Interstate Snow Survey Conference, 1940)
The U.S. Forest Service research on snow started in 1910 as part of the Wagon Wheel Gap study on the effect of forest thinning on streamflow. Results of experiments conducted in forest areas of Colorado, Utah and Idaho show that forest cover retard the spring melting of snow by prolonging the runoff period up to 10 days. Current research includes the intensive study of the hydrology of 3 major watersheds in California. It is planned to modify the forest cover after completion of the study and to determine the effects of the treatment on streamflow in the Wasatch Plateau, in a portion of the Colorado River watershed, the State of Pennsylvania, and on the Smith River watershed in New Hampshire. More research is required to secure adequate watershed service and management.Discussion by J. Cecil Alter, J.E. Church and R.T. Gisborne.
Keywords: Snow research, Watershed management

Improvement of snow survey equipment - Cowgill, P.G. (8th Annual Western Interstate Snow Survey Conference, 1940)
Orange shellac is considered superior to white shellac for coating snow sampler tubes because of the ease in locating bare or chipped spots. Scotch drafting tape is satisfactory and inexpensive substitute for adhesive tape to cover the inspection ports during the shellacking of the sampler. Fleece lined rubberized gloves were found superior to woolen mittens in the field because of their water proofing qualities and insulation from warm hands on the tubes. An amber plastic face mask is exhibited for protection to the eyes and face.
Keywords: Snow safety, Snow sampler maintenance, Snow sampling equipmemt

Some handy kinks for field use - Cowgill, P.S. (8th Annual Western Interstate Snow Survey Conference, 1940)
Practical field experiences are related, especially for coating duraluminum sampling tubes with orange shellac. Satisfactory results are obtained except where the coating is chipped off due to rough handling in cold weather. Improvements made on the sampling tube carrying cases, to include two storage straps, one for each shoulder to hold the case perpendicular in the center of the back, thus leaving both arms free for poling on skis, and maintaining better balance. Rubberized gloves are found to be a great aid when handling the sampling tubes, thus keeping the hands dry as well as the tubes, thus preventing the tube from becoming warm from handling with bare hands. This prevents water on the tube that freezes to the tubes and causes them to stick to the snow, inside and out. A question and answer session was included.
Keywords: Snow sampler tubes maintenance

Ski etiquette and ski safety - Crouch, J.C. (8th Annual Western Interstate Snow Survey Conference, 1940)
The rapid growth of winter sports, especially skiing within National Parks and National Forest areas has demanded an increase of accessible roads during the winter season are described. Due to the great number of beginners in these sports the rules of the road are spelled out in detail s well as the rules for skiing on the crowded slopes and ski tows. Largely simple ski etiquette is involved in ski safety. Eight items are discussed and listed.1)Use your own equipment, do not borrow on the hill.2)The fast skier has the right of way, beginners should stay on the bunny slopes.3)Fill in your ‘Sits Marks’, like replacing your divots.4)When cross-country skiing, always travel in pairs.5)Avoid stepping on another’s skis.6)When skiing on trails stay on marked routes, no short cuts.7)Respect the rules, regulations and property, buildings and equipment of the establishment operating the area.8)Ski safely, ski under control, ski within your limits.
Keywords: Safety, Winter sports

Present trends in improving forecasting in the Humboldt Basin, Nevada - Elges, C. (8th Annual Western Interstate Snow Survey Conference, 1940)
A hydrologic history of the Humboldt River in Central Nevada is presented. The geophysical features that cause so many discrepancies in the climatic changes and resulting difficulties in forecasting streamflow from the area are discussed. Mention is made of the 1910 flood and an attempt at analysing the causes from fragmentary hear-say data is given. Progress is reported in establishing climatological stations and some 31 show courses that will aid materially in the future to forecast the flow of the streams at the Paradise gaging station. Irrigation diversions are being measured.
Keywords: Water supply forecasting, Water supply forecasting

Problems of using calcium chloride in precipitation gages - Elges, C. (8th Annual Western Interstate Snow Survey Conference, 1940)
Cans of aqueous solution of Calcium Chloride of various concentrations were placed in a low temperature room at temperatures varying from -6 to -30 deg F. The results confirm data in the Chemical Engineers Handbook by John H. Perry (1934). An 8-in. gage charged to protect an expected 10 inches of precipitation to -20deg F will require an initial charge of 26.9 lb. commercial Calcium Chloride and 35.8 lb. water. The storage precipitation gage is not recommended if the gage must be unattended for month or more at below 0deg F temperatures.
Keywords: Calcium chloride, Storage precipitation gages

Unit -- hydrograph - Elliott, R.H.; Sherman, L.K. (8th Annual Western Interstate Snow Survey Conference, 1940)
The application of the Unit-Hydrograph method of forecasting floods from rainfall is described. The same basic principals are suggested for designing a procedure of forecasting floods from snow covered portions of the river basin. The Unit-Hydrograph procedure involves searching the several snowmelt factors, to establish the unit of time with the unit of snowmelt resulting in a unit of runoff volume. These units are applied to the area of the basin involved. No sample calculation is presented.
Keywords: Flood control prediction, Snowmelt and runoff, Unit hydrograph

Revised procedure for forecasting the spring runoff above Fort Peck - Freeman, D.B. (8th Annual Western Interstate Snow Survey Conference, 1940)
The accuracy of the forecasting procedures for the Missouri River above Fort Peck Reservoir is shown to be improved by adding weighting factors to precipitation data and from additional sophisticated statistical methods to test the factors for correlation coefficients and also to make full use of the snow survey courses installed in the headwaters areas along the Continental Divide in 1934.Graphical solutions show the effects of the corrective methods.
Keywords: Graphical analysis, Water supply forecasting

Prospective dry years and their cause - Gillette, H.P. (8th Annual Western Interstate Snow Survey Conference, 1940)
Climatic cycles are studied by investigating geological phenomena, shown by terraces around lakes and seashore, paired beds of rock formations and differing materials. The various geological periods and sub-periods are divided on climatic changes. These geologic periods are studied to obtain the effects of climate. The cycles are computed by geometric progression series, assuming that the cycles are harmonic. Geologic formations are pictured and 1 cycle graph is shown with tables of triple progression cycles showing length of time. These cycles extend much further back in history than the tree ring cycles.
Keywords: Cycles geologic

Quantitative method of forecasting runoff from snow surveys - Hall, L.S. (8th Annual Western Interstate Snow Survey Conference, 1940)
The three popular methods of forecasting streamflow by using snow survey data are discussed and evaluated. The percentage method, the area method, and the quantitative method. Although the quantitative method, which is largely empirical, produces satisfactory results for the Mokelumne River basin in California, when used for predicting streamflow for municipal supply for the East San Francisco Bay Municipal Water District. Area elevation data are used together with snow water content, precipitation data in the lower elevations. It is demonstrated that the quantitative method of forecasting runoff from snow surveys is practical, and future studies will point the way to improving the technique so that accurate results can be obtained over a wide range of climatological conditions. Formula, tables and graphical representations are shown, as well as forecast comparisons with actual flow.
Keywords: Elevation methods, Quantitative method, Water supply forecasting

Hydrological investigations for Mud Mountain Reservoir - Hopkins, G.F. (8th Annual Western Interstate Snow Survey Conference, 1940)
The various hydrological factors pertaining to the White River basin, one of the coastal streams in western Washington are analyzed for the purpose of planning the operation of the Mud Mountain Dam, a flood control project. Access to the basin is limited to one road up the main valley and over Cayuse and chinook Passes to the east. Access to tributary streams is by foot and difficult traveling. A network of meteorological stations was established. Snow survey courses were laid out to augment the data for possible flash flood conditions. Data and curves are exhibited and a plan of operation discussed.A formal discussion with data and alternate plans are presented by J.C. Stevens and remarks by F.M. Veatch.
Keywords: Precipitation network, Snow survey networks

Snow types met in highway snow removal - MacVicar, J.D. (8th Annual Western Interstate Snow Survey Conference, 1940)
Snow falling on the west slopes of the Cascades in Washington is usually of the wet type with large flakes of soft texture. Snow falling east of the Cascades’ summit is usually dry snow of small flakes due to the colder temperatures. ‘Tapioca’ snow is peculiar to the Columbia River area in Southern Washington, and consists of snow globules which form a slush soon after falling. High velocity north westerly winds during rain storms at temperatures around freezing, form an icing within a few minutes after falling. A third common snow type is a dry, fine drifting powder which is hard to compact and easily shifted by changing winds. Snow removal from highways with primitive and modern equipment is illustrated in photographs.
Keywords: Snow classification, Snow removal highways

Measurement of foothill springs to determine soil moisture and ground water conditions in the Snake River Basin, Idaho - Marr, J.C. (8th Annual Western Interstate Snow Survey Conference, 1940)
The variation of the flow of shallow springs may provide an important index to ground water conditions beneath the snow pack and affect the amount of runoff. By adjusting the water content of the snow pack accordingly the forecast may be improved. A network of 20 springs along the foothills of Idaho’s Snake River are being measured with the thought of developing another independent variable for the forecasting formulas. Such an index could be used as a soil priming factor. Forecasting procedures and graphs are illustrated and a location map of the network of springs is exhibited, together with data collected over 2 years are tabulated.
Keywords: Soil priming - shallow springs, Water supply forecasting

Problems of the Division of Irrigation in forecasting water supplies - McLauglin, W.W. (8th Annual Western Interstate Snow Survey Conference, 1940)
The progress made by the Soil Conservation Service, Division of Irrigation in the field of snow surveys and irrigation water supply forecasting since its inception of the program authorized by Congress in 1935 is reviewed. With the cooperation of Dr. J. E. Church and Professor George D. Clyde the west-wide program in 1940 includes reports from 753 snow survey courses in the major river basins of the West. Although several areas are undeveloped, time will solve the many problems encountered. The cooperation of many Federal, State and private agencies have made possible a rapid expansion. Monthly snow survey bulletins and water forecast data are being duplicated and mailed to thousands of offices from January to May. This information is finding it’s way into the hands of engineers for better irrigation practices and water storage operations.
Keywords: Snow survey history

Precipitation characteristics west of the Cascade Mountains - Merryfield, F.; Warren, V. (8th Annual Western Interstate Snow Survey Conference, 1940)
A report is made relative to a study to find a means of forecasting the probable flow of streams west of the Cascade Mountains in Washington and Oregon. Precipitation data from eleven Weather Bureau stations with complete 30-year record, 1899-1929 are used. Statistical methods are used without success to build a satisfactory formula. However, the study revealed characteristics of precipitation patterns for the area involved as outlined in eleven (11) statements in the conclusions.Discussion is presented by Norbert Leupold, Corps Engineers, Portland and also by Elmer Fisher of the US Weather Bureau, pointing out factors developed by those agencies for forecasting streamflow.
Keywords: Hydrology basin characteristics, Precipitation analysis

Formation of snow crystals in the mountains and in the laboratory in Japan - Nakaya, U. (8th Annual Western Interstate Snow Survey Conference, 1940)
Snow flake crystallization is studied and classified with respect to the climatology of the various zones of the atmosphere through which they pass in reaching the earth’s surface. The procedures used in handling these fragile crystals are described. Temperature, water vapor and atmospheric conditions create different crystal types. A duplication of natures process is constructed in the laboratory in northern Japan where natural and synthetic crystals are photographed. By a study of snow crystals the character of the upper air can be predicted. A time lapse picture showing in color, the process of snow crystal formation, was shown in beautiful color by microphotography.
Keywords: Snow crystals

Comparison of forecast and actual results, 1939 - Paget, Fred (8th Annual Western Interstate Snow Survey Conference, 1940)
A round table discussion of water supply forecasts made in 1939 is presented in 10 short papers. Forecast volumes are compared with actual streamflow figures as indicated in several tables, for the following sections involved: Nevada - Eastern slope Sierra, H.P. Boardman & George Devor; Central Nevada - Humboldt Basin, Carl Elges; California - Western slope Sierra, Fred Paget; Owens River, James E. Jones; Huntington, Florence, Shaver Lake, William Lang; Utah - Cooperative snow surveys, George D. Clyde; Colorado - East slope Cont. Divide, Ralph L. Parshall; Colorado River - Lake Mead, D.B. Freeman; Columbia River - BC Canada, R.C. Farrow; Powell & Fraser Rivers, Canada, BC, R.C. Farrow
Keywords: Forecast accuracy

Forms for recording and reporting measurements - Parshall, R.L. (8th Annual Western Interstate Snow Survey Conference, 1940)
A series of 12 office forms are exhibited and explained, for keeping record of all phases of snow survey information in order for easy reference when needed. A sample of a snow course sketch map is shown together with an explanation. These sketches are made on tracing material for duplication, to be included with the field equipment for ready reference when at the snow course. A form check list is shown for making sure that the field man has all the necessary equipment for traveling and measuring the snow.
Keywords: Snow survey office forms

Ice in the northern streams of the United States - Parsons, W.J. (8th Annual Western Interstate Snow Survey Conference, 1940)
River water is cooled by the air but temperatures are kept almost uniform by turbulence. Needle-like crystals of ice form on the surface and act in one of 3 general ways. The crystals are carried below the surface in turbulent streams as a mixture of ice crystals and water called Frazil ice. The ice crystals join to form floating islands of ice in less turbulent streams. These pans of ice float to shore, unite with others to form an ice cover over the stream. A clear sheet of ice forms from the floating ice island in quiet streams. The rate of freezing decreases when an ice cover forms because of friction of ice surface. The ice under the surface soon melts smooth, reducing the friction. Pressure caused by ice expansion usually results in buckling in weak areas but bridge piers, bulkheads, and sea-walls can be damaged. Ice melts from the surface in spring. the melt-water seeps through cracks forming a honeycomb structure which is disrupted by the rising spring flow.
Keywords: Ice - Frazil, Ice - river

The relation of snow to maximum flood peaks - Parsons, W.J. Jr. (8th Annual Western Interstate Snow Survey Conference, 1940)
A method of predicting floods originating in mountains with deep snow covers is described. Snow precipitation, rain, snow cover and snow melt data are used to develop a synthetic hydrograph for each elevation of the snow line. The maximum flood hydrograph and the estimated location of the snow wedge are used for forecasting purposes. Flood data on several California, Oregon and Washington river basins are discussed.
Keywords: Flood control prediction, Snow melt and runoff

Do climatological averages serve adequately as normals? - Pedersen, C. (8th Annual Western Interstate Snow Survey Conference, 1940)
A discussion of the objections to the use of the arithmetical average or mean as a parameter to express the normal climatological values; as normal rainfall, normal temperature or the percent normal. The normal value should represent the most common value of a series with a probability of being equaled or exceeded approximately 50% of the time. The infallibility of this occurrence is illustrated in an array of tabulated data. It is suggested that another parameter be used to express the normal values from a series; the median; the mode; the geometric mean; or the harmonic mean. It is further suggested that in speaking about the arithmetic average or mean that the term normal not be used.This matter became a resolution to the Secretary of the Section of Hydrology of the American Geophysical Union for a nationwide acceptance.
Keywords: Climatological data, Normals

The snow melt problem as affecting the design of flood control works - Rugen, O.N. (8th Annual Western Interstate Snow Survey Conference, 1940)
Snowmelt, rainfall and meteorological conditions are studied with relation to abnormally high stream flows. Previous floods caused by various combinations of these factors are reviewed and references to other studies involving snowmelt problems are quoted. The storage effect of a snowpack on rainfall in various quantities of snow, rain, infiltration rates, temperatures effecting flood producing potentials are cited. The thermodynamics of snowmelt are included in the development of formula and graphical solution, all shown and discussed in the paper.
Keywords: Flood control prediction, Graphical analysis, Snowmelt runoff

Improvements to the Tucker motor-sled to surmount difficulties in traversing powder snow - Ryan, J.T. (8th Annual Western Interstate Snow Survey Conference, 1940)
The Tucker motor-sled was demonstrated on the slopes of Mt. Rose region south of Reno. The motor-sled made 3 runs. It is driven by a helical thread wound on a revolving drum, and is powered by a 15 hp air-cooled gasoline engine. total weight is 500 lbs. The sled showed a tendency to slip sideways on a 12% grade. The drum dug the snow away from itself when breaking through hard snow crust, or encountering soft snow. The machine is light, built sturdy, has a cruising speed of 5 mi/hr, and can carry 2 men up a 30-40% grade without great effort. More weight caused the motor-sled to break through the snow crust and stall. It is questioned that improved performance in soft snow could be obtained if the major portion of the weight were carried by the out-board skis instead of on the drum.Discussion by E.M. Tucker indicates that the sled is being redesigned and a Franklin air cooled motor of 80 hp is being installed at no addition in weight.
Keywords: Over snow vehicles, Tucker snow-sled

A quantitative forecast system of runoff based on snow surveys at the mean elevation of snow cover - Salo, J.V. (8th Annual Western Interstate Snow Survey Conference, 1940)
The mean-elevation method of making rapid calculations of potential water supply is described. The water content was measured by the zone method and the mean-elevation in two areas. This zone method gave values 10% higher than the mean-elevation method. Graphs are developed to show the relation between elevation and area as well as the relation of elevation and water content as measured by snow surveys. Due to the large area of the Merrimack River basin, some 3100 sq. mi., and the difference in climatic conditions that may change rapidly due to warm rains and cause floods. The snow survey trips necessitate a 600 mile trip taking 5 days of time to complete one survey. This method of forecasting makes possible; (1) the immediate calculation of potential water supply, (2) estimates of runoff in adjacent basins, (3) the use of component basins, (4) provides a way to follow the trend of the coming runoff. With 15 power plants along the stream, this is important.
Keywords: Elevation methods, Water supply forecasting

Tests of Mount Rose Snow scale No. 101 - Stevens, J.C. (8th Annual Western Interstate Snow Survey Conference, 1940)
Three sets of tests were made on the Mt. Rose snow scale No. 101. An initial load of 3 lb. (47.1) inches of water was applied. The index set to zero, and successive 1 lb. loads were added without unloading the springs. All readings showed less than 1% error in test No. 1. To begin test No. 2, a 2.31 lb. (36.3) in water load was added initially and successive weights added. The largest error was 1.32%. The load was removed after each scale reading in test No. 3, and the index adjusted to zero before the next load was applied. The largest was less than 1%. Loads up to 27 lbs. (400 in. water content) were applied in the 3 tests. Some evidence of fatigue was shown in the high loads. Data from the 3 tests are shown in tabulation and graph is plotted for visual inspection.In discussion by the John Chatillion & Sons Co., of New York, three models of snow survey scales are pictured and a discussion in text form is shown with a calibration chart.
Keywords: Snow scales test accuracy, Snow survey equipment

Winter overflow from ice gorging on shallow streams - Stevens, J.C. (8th Annual Western Interstate Snow Survey Conference, 1940)
Large quantities of frazil ice in shallow streams increase viscosity, decrease velocity, and increase the stage of the stream. High banks accommodate the increased stream state by allowing the rising frazil ice to form a bridge under which normal flow continues. Overflow occurs where stream banks are too low to contain the river stage. Low spots are filled with ice; the banks are built up with deposited slush ice, and a new river is formed. The ice-gorging and winter overflow of the Madison River was studied to ascertain whether the operations of the Hebgen and Madison reservoirs were responsible for the overflow in the 1916-17 season. An analysis of weather conditions for that period indicated that the overflow was caused by a sustained cold spell and not by reservoir operations. Photographs illustrate the ice blocked Madison River, overflowing farm lands. Ice forming factors are shown by graphs.
Keywords: Floods - ice, Ice - frazil

Snow activities - National Park Service - Waterhouse, R.D. (8th Annual Western Interstate Snow Survey Conference, 1940)
The intensive cooperative program in snow activities of the National Park Service in Region IV of that agency is expanding rapidly. The several National Parks in California, Oregon and Washington are taking an active part in the field work of the West-Wide Snow Survey Program. Rangers are combining this work with their regular Park Patrol trips during the winter months. Aside from personnel the Park Service is furnishing shelter cabins and short-wave communications. With the ever increasing demands of winter sports information a program of disseminating snow conditions to newspapers and radio stations has developed into a complicated bit of business to the National Park Service, requiring training of personnel in the supervision of these activities for safety and economic operations.
Keywords: Winter sports area reporting

A plan for the study of snow cohesion and snow loads in estimating the necessary strength of roofs against snow overloading - Work, R.A. (8th Annual Western Interstate Snow Survey Conference, 1940)
A one-sixth scale model of a deep-snow shelter cabin was prepared for snow load tests. An estimated 12.5 tons of snow was seen on an actual shelter cabin roof. The snow covered the cabin completely and is not known whether the full load was borne by the roof of whether part of the mass was supported by cohesive action of the lower snow strata. It is suggested that a removable roof be used on the scale model for accurate measuring of the load capacity. Discussion by Dr. J.E. Church has no solution to the stress problem in buried cabins under snow.
Keywords: Snow loads on roofs

Reports of water supply forecast accuracy for 1939 - Work, R.A. (8th Annual Western Interstate Snow Survey Conference, 1940)
The accuracy of water supply forecasts is reported by the several area offices publishing forecasts during the snow season of 1938-39 for the major streams in the western states and Canada. Streams are listed and values are tabulated and discussed by the several authors.Oregon Streams, R.A. Work and J.H. Ryan; Idaho Streams, James C. Marr; Washington Streams, Walter E. Johnson; Montana Streams, O.W. Monson; Missouri (Fort Peck), D.B. Freeman; British Columbia, R.C. Farrow; Alberta Canada, W.T. McFarlane.
Keywords: Water supply forecast accuracy

Standards and terminology - Work, R.A. (8th Annual Western Interstate Snow Survey Conference, 1940)
A recommendation of a procedure for reporting Forecast Accuracy of streamflow forecasts in terms of the mean flow as measured by the USGS Surface Water Branch. A schedule of arithmetic values with corresponding word descriptions is advanced.Percent AccuracyWord Definition5%Excellent5 to 10% Good10 to 20% Fair20 to 30% PoorMore than 30% Very poorGeneral consensus of this schedule was discussed by members of various agencies.
Keywords: Water supply forecast accuracy

Small watersheds - Bonner, J.P. (7th Annual Western Interstate Snow Survey Conference, 1939)
The relation between snow survey data and runoff from small watersheds is difficult to assess especially where part of the watershed is in the rainfall altitudes. Very frequent measurements of snow courses are necessary together with rain gage measurements and other meteorological and soil moisture data is required to fill in the desired information necessary when working with small watersheds. No information is given as to the size of the so called small watershed, or what altitudes are involved.
Keywords: Snow melt and runoff

Relation of fall streamflow to spring runoff - Eagle, H.C. (7th Annual Western Interstate Snow Survey Conference, 1939)
Precipitation measurements and snow survey data together with fall runoff (mean October, as an index to soil priming and groundwater conditions) are used in water supply forecasting procedures, for the Yellowstone River, Montana. Data exhibited in the table form the basis for a regression equation. Results of actual and forecasted values are shown on a graph. October runoff is weighted by cut-and-try procedure, which reduces the forecast error. Winter and spring precipitation are also adjusted. These adjustments are show in tabulations and are also plotted on a histogram to show the effects of the adjustments.
Keywords: Fall precipitation, Fall streamflow, Water supply forecasting

The influence of autumn rainfall on the runoff from melting snow - Farrow, R.C. (7th Annual Western Interstate Snow Survey Conference, 1939)
A report of a study of ‘Soil Priming’ effects on seasonal runoff as related to the water supply forecasting on the Okanagan River, British Columbia. A soil moisture deficiency curve is developed from fall precipitation data and runoff data over a 14 year period (1923-37). Estimates from the curve are used to adjust the seasonal runoff in percent of normal flow. Statistical procedures are used. A table of data is exhibited and plotted graphs illustrate the effects on seasonal runoff.Discussion by R.E. Horton is included.
Keywords: Fall streamflow, Precipitation, Soil priming, Water supply forecasting

A limit of practicable usefulness of snow surveys for forecasting runoff at Ft. Peck Montana - Freeman, D.B. (7th Annual Western Interstate Snow Survey Conference, 1939)
The prediction of the Missouri River flowing into Fort Peck Reservoir presents many problems where the reservoir is 225 miles east of the nearest snow survey course. The river transverses an entirely different environment from the headwaters basins. Many unmeasured diversions are encountered as well as unmeasured tributary streams. Precipitation data appeared to show a better relation to percent normal than the snow survey data, probably due to the remote location of the reservoir and the large area in the rain fall altitudes. In order to produce a more reliable forecast from snow surveys a longer record of data is needed and considerable study will be necessary.
Keywords: Precipitation data, Water supply forecasting

Northern Rocky Mountains - Gisborne, Harry T. (7th Annual Western Interstate Snow Survey Conference, 1939)
The values of snow surveys are shown to have a very high correlation to runoff when used relatively close to the source. This data is most useful in predicting forest fire hazards and how serious the fire potential will be during the late summer and fall months. The U.S. Forest Service is deeply involved in cooperation with other agencies in the field work of snow survey measurements. The data collected is being found very useful for other purposes than forecasting the probable streamflow.
Keywords: Forest fire hazard

Effect of soil priming to spring runoff by fall precipitation on the upper Snake River - Marr, J.C. (7th Annual Western Interstate Snow Survey Conference, 1939)
The effect of fall precipitation as a soil priming factor in predicting irrigation water supply from April first snow survey data is presented. Graphical analysis are illustrated and discussed. Snow survey data at nine courses, and precipitation data for April, May and October at Moran, Wyoming, are tabulated and used in the analysis. Forecasts are determined from the graphs illustrated. Discussion by H.T. Gisborn, Lynn Crandle, O.W. Monson and J.E. Church are included.
Keywords: Antecedent precipitation, Fall precipitation, Snow data, Soil moisture, Water supply forecasting

Analysis of snow cover and runoff in upper Snake, upper Yellowstone and Swift Current watersheds - Monson, O.W. (7th Annual Western Interstate Snow Survey Conference, 1939)
Snow survey water content measurements are used as a basis for forecasting irrigation water supply, together with other factors closely allied with snow melt. Four factors are listed, (1) rainfall during the runoff period, (2) rainfall during the fall months before snow fall, contributing to soil priming and groundwater recharge, (3) deep percolation losses, (4) evaporation and transportation losses and sublimation of the snow pack. Measurable factors are by correlation coefficient values. A regression equation is developed and the least squares line is drawn through the plotted points on the graphs as a means of visual inspection. A discussion of the results of the study is included in the text of the paper.
Keywords: Snow surveys, Soil moisture, Stastical methods, Water supply forecasting

Correlation of headwater streams of the North Continental Divide - Monson, O.W. (7th Annual Western Interstate Snow Survey Conference, 1939)
Snow surveys as an index to volume of runoff is shown to be most reliable on high elevation watersheds where the bulk of the runoff comes from melting snow. A historical record of snow survey data and a parallel record of runoff data are necessary with sufficient years of record to show the possible variation of the dependent and independent variables, runoff and snow respectively. Statistical methods are used to provide a degree of correlation by solving for the correlation coefficient (rxy) snow survey data from one or more courses as (x) and the seasonal runoff (May 1-Sept.30) (y). Results of a study made on several basins are shown in tables. A regression equation is built of the snow courses that show the highest correlation coefficients with runoff and used as a forecasting tool, rather than a graphical solution.
Keywords: Statistical methods, Water supply forecasting

Accuracy of Mount Rose spring balance - Stevens, J.C. (7th Annual Western Interstate Snow Survey Conference, 1939)
A comparison was made of the relative accuracy of the Mt. Rose spring balance as improved by the Leupold, Vopel and Company of Portland, Oregon, and the Chatillon type with iso-elastic springs. The improved balance was within the limits of observational error of ordinary field work. It is believed that the accuracy of the simple springs can be further improved. The graduations were not tested for accuracy of machining.
Keywords: Snow survey equipment, Weighing scales

Construction of snow survey shelter cabins - Work, R.A.; Parshall, R.L. (7th Annual Western Interstate Snow Survey Conference, 1939)
The details of construction of a Snow Surveyors Shelter Cabin is presented. The need for such a structure is explained, featuring safety to men from storm or bitter cold weather fatigue. A food supply is stored in compartments to prevent freezing, sleeping bags and utensils are also available. Dimensions and roof structure are shown taking into consideration snow loads. A Santa Claus chimney is also constructed above the house to allow for access if the cabin is completely buried. This does away with much shoveling of snow at the end of a hard day’s travel. Also a lower access is made available through the attic on the gable end. A log cabin is shown for use where no access road is available in the dry season, as well as a frame construction cabin. All miscellaneous parts are pre-cut and marked for assembly. Cost figures for 1927-39 are included and a list of materials. Discussion by Dr. J.E. Church is included.
Keywords: Snow survey shelter cabins

Outline of Weather Bureau Northeast states winter sports service - Bernard, M.l (6th Annual Western Interstate Snow Survey Conference, 1938)
An outline is presented for developing a winter sports reporting service by the Weather Bureau. Snow conditions are to be gathered from seven districts, assembled and reported by radio, telegraph, and news papers throughout the Northeast states. Outlets will also be from the District Weather Bureau offices as indicated on the location map. A check list reporting form is shown and a revised nomenclature of snow conditions with a coding procedure for economy in telegrams and teletype messages. Samples of summary snow sports bulletins together with weather forecasts for the area involved are illustrated and shown.Discussion by several authorities of the Western states is included.
Keywords: Winter sports reporting service, Winter sports snow conditions, Winter sports snow nomenclature

Shielded storage precipitation gages - Codd, A.R. (6th Annual Western Interstate Snow Survey Conference, 1938)
The shielded storage precipitation gage designed by J. Cecil Alter consists of a galvanized iron framework as illustrated in the photograph. The shield is made of strips of galvanized sheet iron, hung on a one-quarter in. hoop 36 in. in diameter. The shield leaves are hung on the hoop with bent wires on each side and spaced at the top and bottom by brass chain. The gage is a standard Weather Bureau rain gage outer shell 8 in. in diameter, and is held in place by a metal collar at the bottom and a swivel hoop at the top for removing the gage for weighing the solution of calcium chloride and water at 33.4% by weight. The solution keeps the gage from freezing and evaporation is prevented by an oil film. The original charge of approximately one quart of water solution is weighed for the original weight and then weighed at intervals of daily, weekly, monthly or after each storm as desired. Each weighing is entered and the previous weighing subtracted to obtain the inches of rainfall or snowfall that has occurred during the interval. At the Mountain Snow Fall Stations, 5 gages are erected about 200 feet apart and on approximately a square with one in the center.
Keywords: Precipitation gage shielded storage

Applying the Chatillon iso-elastic springs to the Mount Rose spring balance - Elges, C. (6th Annual Western Interstate Snow Survey Conference, 1938)
Temperature variations affecting the elasticity, creep and hysteresis of the metal of the springs and deviations from the shape in the stresses and transmitting machinery cause inaccuracies in spring scales. A new spring developed by J. Chatillon and Sons, made of an alloy called Iso-Elastic Metal eliminated the effects of temperature changes in the spring. The creep at stress of 60,000 lbs/sq in was reduced to less than 0.02% in deflection. The hysteresis was not over 0.02-0.04% of the full load deflection. A linear relationship of spring between load and deflection was obtained by using wire coiled with the axis of the wire parallel to the axis of the helix. Iso-Elastic springs were used in a Chatillon spring scale weighing 6 lbs, 5 oz. which gave an accuracy of 99.92%. A Mount Rose type of spring balance scale weighing 2 lbs. 12 oz. was constructed using Iso-Elastic springs. Further development of the scales is necessary to reduce it in size and weight before it can be used for snow surveys.
Keywords: Snow scales spring balance, Snow survey equipment

Improvements in the methods of forecasting streamflow - Elges, C. (6th Annual Western Interstate Snow Survey Conference, 1938)
Various methods of forecasting streamflow from snow surveys are reviewed. Data for Lamoille Creek, Nevada in 1938 are used to compare 3 different systems of obtaining average water content of the snow cover. Boardman’s Percent Normal System, and the direct curve method of computing the average water content are illustrated. The direct method retains all the desirable features of the percentage system yet eliminates computing normals and percentages.Discussions are presented by Fred H. Paget, J.E. Phillips, James C. Marr, and R.D. Goodrige.
Keywords: Water supply forecasting, Water supply forecasting methods

Anodyzing or hardening the surface of snow samplers - Marr, J.C. (6th Annual Western Interstate Snow Survey Conference, 1938)
Anodyzing duraluminum equipment hardens and smooths the surfaces, prevents oxidation and discoloration of hands and clothing, and increases the durability of the equipment. Anodyzing is recommended for snow samplers. The smoother surfaces permit the snow cores to slip through the tube easier, and less wear is exerted on the threads of the couplings. It is suggested that the cost of anodyzing may outweigh the advantages.
Keywords: Snow samplers, anodyzing

Status of proposed bulletin of principles and practice of snow surveying - Marr, J.C. (6th Annual Western Interstate Snow Survey Conference, 1938)
A progress report on a new Snow Survey and Water Supply Forecasting Procedure Manual, under preparation and to be published by the Department of Agriculture as one of their bulletins. The manual is described and the essential needs of water supply forecasts from snow surveys are enumerated. The care of snow sampling equipment and its use in the field are covered together with field office procedures, improvements and maintenance of snow courses. Procedures for preparing historical data for forecast analysis and winter travel, by skis or snowshoes, safeguards and suggestions as to stop-over cabins and stored supplies, all these items are covered and many more. Contributions have been included and edited from all available authorities in snow surveying.
Keywords: Snow survey procedures

Need of higher level snow survey courses in the Colorado River drainage area of Western Colorado - Merriell, F.C.; Hinderlider, M.C. (6th Annual Western Interstate Snow Survey Conference, 1938)
Copies of correspondence received by Dr. Church are exhibited to show further need for an intensified network of snow courses at high elevations. The need for more wide spread information on tributary river basins is more and more evident. The main problem appears to be a lack of funds to finance the installations and maintenance costs throughout the coming years. Correspondence indicates that work is very slowly being accomplished towards this end through the cooperation of the Weather Bureau with a network of storage gages in the mountainous areas of Arizona, and the Agricultural Engineers establishing a limited number of courses as finances are available through their Colorado and Idaho offices.
Keywords: Snow survery networks

California cooperative snow surveys, directions, suggestions, and hints for snow surveys - Paget, F.H. (6th Annual Western Interstate Snow Survey Conference, 1938)
Directions for the maintenance of snow samplers and snow sampling procedures as practiced in California are outlined. Methods are described for removing dents from samplers, shellacking, keeping threads cleared, sharpening and/or changing the cutter, and carrying the tubes. Precise step-by-step instructions are given for making and recording a sampling including sources and detection of errors and after-care of samplers. It is suggested that winter snow travel is facilitated by using adequate foot gear, recommended clothing, dark glasses, and minor items for emergencies. Shelter cabins should be stocked each year before winter with an adequate supply of food and fuel. A sample grub list is given.
Keywords: Snow samplers maintenance, Snow survey procedures

Improvement in Mount Rose spring balance tickling corky snow - Paget, F.H. (6th Annual Western Interstate Snow Survey Conference, 1938)
The accuracy of the Mount Rose spring balance can be improved by providing a spring to hold the rack in close contact with the rotating pinion controlling the indicator, and by making the rack thick and of durable metal. A small swivel connecting the top of each spring to the head frame, would facilitate making necessary adjustments. The snowpack of 1937-38 was typical in that accumulation began late and piled up rapidly. Metamorphism converted the upper layers to a coarse grainy snow, but the lower layers remained fluffy ('Corky Snow'). This condition made sampling difficult. The problem was solved by allowing the tube to penetrate by gravity with minimum rotation. The method was called 'Tickling the tube through' fluffy snow.
Keywords: Snow sampling procedures, Snow survey equipment

Paraffin versus enamel: optimum nuimber of sampling points: improvement of tubular balance - Paget, F.H.; Ryan, J.T. (6th Annual Western Interstate Snow Survey Conference, 1938)
Hard varnishes, such as Risch-Rasch, on the inner surfaces of duraluminum wear out unevenly and result in rough surfaces. Removal of the varnish with strong caustic is inadvisable with soft duraluminum; removal with alcohol or paint remover is time consuming. Tubes coated with paraffin last one season and are adequate to prevent clogging. Spare lower joints may be carried along when heavy service is anticipated.Devore recommends 16 sample points in snow courses. Six or seven sampling points in snow courses have been found adequate in the King’s River watershed. Fewer samplings are desirable in order to preserve the tube coating and to reduce time and labor costs.It is recommend that the 20-ft-capacity scales of samplers be graduated below the 140 inch mark to 220 in. Such an adjustment would require only the extension of graduations to the end of the tube, and would increase the total capacity of the tube by 82 inches.John T. Ryan exhibits a graph of data collected from a test of the Bureau of Agr. Engrs. Tubular Scales No. 388 indicating excellent accuracy if the scales were calibrated from 140 in. to 220 in.
Keywords: Sampler tubes coatings, Snow scales tests, Snow survey courses

Method of applying bakelite to snow sampler - Poulson, W. (6th Annual Western Interstate Snow Survey Conference, 1938)
A bakelite, commercially known as Risch-Rasch, has been used as a running base on skis. Risch-Rasch has proven equally effective in preventing clogging when used on snow samplers. The bakelite, thinned with equal parts of acetone, can be applied by dipping or spraying. Three to four applications at 12 hour intervals are sufficient to last a snow sampler several years. No attempt has been made to remove the bakelite, but it is believed that the usual commercial solvent, Fortus might injure the duraluminum sampler. This material was tried on one sampler and no sticking of various types of snow or clogging was noticed.
Keywords: Snow sampler coating, Snow sampler maintenance

Snow surfaces in the high Sierras for skiing purposes - Poulson, W. (6th Annual Western Interstate Snow Survey Conference, 1938)
A classification of snow surfaces as affecting skiing conditions is presented. The terms are used to describe the texture in the Sierra Nevada Mountains based upon the reaction of the skis against the snow surface. Snow surfaces are classified as: -powder, wet, heavy, spring, packed and pitted snow; crust-breakable, unbreakable, glazed, and wind packed slab, or erosion forms. Snow conditions [vary] in the area generally on exposed slopes and slope directions as well as elevation. The classifications are similar to those reviewed in WSC Papers Nos. 57, 58, and 60.
Keywords: Snow classification for skiing, Winter sports

The use of precipitation gage measurements in forecasting the inflow to Lake Mead - Reedy, O.C. (6th Annual Western Interstate Snow Survey Conference, 1938)
With the completion of Boulder Dam and the filling of Lake Mead to maximum capacity, the problem of forecasting the inflow from the Colorado River became evident. Studies have been under way for several years gathering data and analysis work for developing a suitable formula to meet the complex problems involved in operating this huge multi-purpose project. Precipitation gage networks over the main and tributary basins had been intensified, snow survey courses established in the high elevations, evaporation and other pertinent meteorological data measuring stations been established in anticipation of the problem. Trial equations will have to be tested with actual practice to clear the deadwood and introduce new factors before a satisfactory solution is solved.
Keywords: Precipitation gages, Reservoir regulation, Water supply forecasting

Snow activities of the National Park Service - Waterhouse, R.D. (6th Annual Western Interstate Snow Survey Conference, 1938)
A report of the winter sports activities carried on under the supervision of the National Park Service, within the several National Parks of California and Oregon. These activities have been carried on for the past five years with amazing rapidity in the numbers of people taking part in skiing and ice skating. New areas are being opened with good success for the concessionaires. Snow conditions are reported by the Park Service to outside interests. Snow removal equipment is being used to open roads that otherwise would remain snow bound until spring crowds become evident.
Keywords: Winter sports areas, Winter sports reporting service

Skiing in Southern California: Essential equipment - Younquist, R.C. (6th Annual Western Interstate Snow Survey Conference, 1938)
Winter sports areas in Southern California in close proximity to Los Angeles are described. The area near San Gorgonio where elevations of 11,000 are accessible is particularly adapted to mountain ski trips with very good slopes and enchanting scenery. Types of equipment are described and explained. Snow conditions experienced in a trip through the area in the winter are described. Plans for future development of the areas and ski lifts are mentioned.Discussion by George A. Lewis relates incidents in cross country travel on skis and recommends beeswax for dry snow and a resin wax for wet snow. Types and make or trade names are quite a controversial problem and likely to be of a personal decision. However, ski climbers are almost a necessity to save energy when long up hill climbing is involved along the trail.
Keywords: Winter sports area development, Winter sports equipment

Classification of snow surfaces - Baldwin, H.I. (5th Annual Western Interstate Snow Survey Conference, 1937)
A classification of snow and crust conditions containing 14 items and definitions is presented. The descriptions are based on reports obtained from stations with more than 4 inches of snow. The snow depth is measured regularly at the same fixed point in a field unaffected by drifts. Soft, dry snow include fluffy, powder, new, and heavy types.Spring snow conditions are described as granular and frozen granular. Crust conditions are referred to as glazed, breakable, wind crust, common crust and icy crust. Some observations on snow conditions reported from New England are included. A dictionary list of acceptable snow surface conditions are listed and definitions are shown.
Keywords: Winter sports classification, Winter sports snow conditions

The expanded program of the United States Weather Bureau in snow work - Bernard, M. (5th Annual Western Interstate Snow Survey Conference, 1937)
Mountain snow surveys for the benefit of irrigation were suggested in 1909 and have been made annually since 1911 on an increasing number of watersheds. The influence of elevation on snowfall is discussed. Precipitation stations will be equipped with storage snow gages and their present number supplemented to give a well distributed network in which elevation, aspect and individual needs of the various basins will be considered. The development of the storage gage is presented. The advantage of the snow storage gage s basin snowfall samplers are enumerated. Streamflow forecasting from snow surveys is discussed. Recommendations are made to overcome the deficiencies of hydrologic research and include improvements of snowfall and snow depth measurements, determination of relations between factors causing snow to melt, and evaluation of surface conditions controlling the losses to runoff from melting snow.
Keywords: Network, Precipitation gage

Further improvement of snow survey apparatus - Church, J.E.; Marr, J.C. (5th Annual Western Interstate Snow Survey Conference, 1937)
The general improvements sought for in snow survey apparatus are simplicity, universality and durability. The new dur-aluminum sampler is subject to snow adhesion which creates difficulties in obtaining a full core sample. Comparative test on steel and dur-aluminum samples were scheduled for the winter. Some of the improvements reported include the hardening of dur-aluminum surfaces of samplers, removable cutters, introduction of variable lengths of sampler sections. Minor corrective measures have effected to spring balances, but further improvements are indicated. An electric weighing scale for snow samplers has been designed but has not been tested. Comments on equipment, by Harold Conkling are included, calling to the spanner wrenches, and driving wrench, and threads of the couplings where seizure of like metals cause trouble, especially soft dur-aluminum.
Keywords: Snow survey equipment

Further observations and tests on duraluminum samplers - Church, J.E. (5th Annual Western Interstate Snow Survey Conference, 1937)
Tests of shellac-coated and uncoated duraluminum samplers under various conditions of snow depth and density, air and snow temperatures were conducted in the Reno, Nevada area. The ease of driving and retrieving the sampler, of removing the core and the conditions of the core were reported. It is concluded that an uncoated duraluminum is unsatisfactory, but with a heavy and uniform shellac coating it will drive as readily as the steel tube also having a coating of shellac, results with the two tubes were equal. It is suggested that laboratory studies be made of the relative conductivity of shellac as compared with duraluminum and steel and effect of heat conductivity on the adhesion of snow and ice to duraluminum and steel with and without shellac.
Keywords: Duraluminum samplers, Snow sampler tests, Steel samplers

Cost and benefits of snow surveying in Utah - Clyde, G.D. (5th Annual Western Interstate Snow Survey Conference, 1937)
Utah’s irrigation water supply is largely dependent upon the size of the winter snow pack stored in the high mountain of the central portion of the state. The type of farm crops are variable in their water requirements. With sufficient accurate foreknowledge of the probable water supply, crops can be selected for economical planting and use of waterThe drought year of 1934 was probably the most serious in western history. Advance information of this condition was indicated by snow survey measurements. A water conservation program was immediately organized with a crash program by Press and Radio information. Strict adherence to regulations and the full cooperation of the farmers resulted in a saving of over $5,000,000 by economical use of water. Supplementary supplies were organized from well drilling in the Bear River Basin resulting in a crop saving of another $3,000,000 in that area alone.Such savings warrant the cost of snow surveys for many years.
Keywords: Economics of snow surveys

Establishing snow courses for representativeness, permanence, and continuity of record - Clyde, G.D. (5th Annual Western Interstate Snow Survey Conference, 1937)
Snow courses should be located in uniform and fairly well protected areas such as, level open forests, parks, or closed basins above winter melting lines. The ground surface should not show signs of standing water and far enough from creeks or stream banks that there is no chance of early flooding. Sample intervals are usually 50 to 100 feet apart. The number of samples usually 10 or 20 are sufficient. Better to have several courses of 10 samples at intervals of altitude than one long course in a basin. It is recommended that courses be accurately mapped, marked cleared, and described on data sheets. Snow survey record sheets should be kept up to date. Consistent records can be obtained more readily if courses are accessible, or if suitable shelter cabins are available. Pictures and sketch maps of courses are shown; also an assortment of data collections sheets, and marker signs for courses.
Keywords: Snow course location

Statistical analysis of sampling on snow courses - Connaughton, C.A. (5th Annual Western Interstate Snow Survey Conference, 1937)
Statistical methods can be used to select sampling points along a snow course to be tested for water content. In the cases reported it was arbitrarily decided that an error of sampling which was plus or minus 10 percent of the average water content for the snow course was satisfactory. Standard deviation was calculated and standard error was taken as a percent of the average. A formula is given to estimate the adequacy of the sampling.
Keywords: Snow survey course analysis, Statistical methods

Improvement in ski, duraluminum sampler, and weighing apparatus - Cowgill, P.S. (5th Annual Western Interstate Snow Survey Conference, 1937)
Skis, waxed to the condition of the snow and equipped with some form of rigid bindings, are used almost entirely by snow surveyors. Experience with the new duraluminum sampler tubes points to the necessity of shellacking them to prevent the snow water from adhering to the bare metal. The tubes work well in warm weather, but on very cold days the core froze to the inside of the tube. The duraluminum sampler tubes will be tried again after being shellacked. Experiments to determine the effect of different temperatures and atmospheric conditions are planned. The Mount Rose Type balance remains the most satisfactory where large variations in depth of snow are encountered.
Keywords: Snow survey equipment, Snow survey samplers

Value of snow surveying in the Tahoe-Truckee basin - Devore, G.W. (5th Annual Western Interstate Snow Survey Conference, 1937)
The economic value of snow survey measurements used in water supply forecasting is well demonstrated in power development along the Truckee River, Nevada, by the Sierra Electric Power Co. Snow surveys are made monthly Jan. through May in order to monitor the progress of the snow build up in the drainage basin. Power plant operations are planned on this information. The regulation of Lake Tahoe water levels within the six ft. legal limit are also anticipated from the monthly snow survey data. Estimates of power generation are made 12 months in advance and are of importance in computing probable operating costs and dividends that will be available to stockholders in the company.
Keywords: Snow surveys economics, Snow surveys power generation

Eastern Sierra snow sports - Diebert, G. (5th Annual Western Interstate Snow Survey Conference, 1937)
A description of the winter sports areas along the Eastern slopes of the Sierra in the neighborhood of Bishop, California. Ski slopes with tows are operating at Bishop Pass, Mt. Tom, Denderberg Mt., Conway Summit and at the Mammoth Lakes and Pass area. Accommodations are available. New areas are being contemplated with chair lifts.
Keywords: Winter sports areas

Possible research projects in snow surveying and stream flow forecasting in the Western States - Elges, C. (5th Annual Western Interstate Snow Survey Conference, 1937)
Recommendations are made for the establishment of one or more mountain meteorological stations to study the factors involved in the occurrences and ablation of snow and snow melt runoff, mainly temperature, snow accumulation, precipitation at the source of the runoff. Evaporation as effected by chinook winds east of the Continental Divide and Sierra, should be investigated. Other recommendations include snow courses of approximately 20 measurements with adequate cross courses, and improvements in forecasting, runoff, lake or reservoir elevations and the effects of forest fires and added protection of protecting the local environment around a snow course.
Keywords: Snow research program

Snow cover conditions for winter sports in the Western States - Ewing, P.A. (5th Annual Western Interstate Snow Survey Conference, 1937)
Winter sports snow conditions terminology has been confused by colloquialisms, terms vary with the number of reports. An attempt is made by creating a symposium, bringing together reporters and knowledgeable ski instructors and experts to set up a set of terms to be used and definitions. Such a listing is exhibited. In the Western Unites Stated, some 2,000,000 people are taking advantage of the winter sports radio broadcasts and newspaper releases. With the cooperation of the National Parks, U.S. Forest, State Parks, and many other companies and private ski tower operators, the reporting program to this ever-growing business is progressing.
Keywords: Winter sports reporting, Winter sports snow conditions

Establishing first year-normals on the basis of accumulated showfall snd some forecasts from runoff ratios - Farrow, R.C. (5th Annual Western Interstate Snow Survey Conference, 1937)
Three snow courses (one in each area) were laid out in 1937 at Glacier in the Selkirks, at Field in the Rockies, and at Fernie in the Southern Canadian Rockies. The location are near various precipitation stations whose data can be related to runoff at higher elevations. Sampling data from the 3 courses, the method used in obtaining a tentative first year normal, the mechanics of forecasting used, and the application of the forecast to points further downstream by use of runoff ratio factors are discussed. The percentage method is compared with the density method in establishing first-year snow course normals. It is concluded that a relationship between snowfall data and runoff is evident and that precipitation during runoff does not affect runoff. A refutation by Carl Elges of the density method is contained in the discussion. (See also SIP U1695 and WSC 35-37).
Keywords: Statistical analysis, Water supply forecasting

Snowfall and runoff in the Canadian Columbia Basin: a study to determine the ideal locations for snow survey stations - Farrow, R.C. (5th Annual Western Interstate Snow Survey Conference, 1937)
Snow courses, representative of runoff at Golden, Revelstoke, Trail, Wardner, and Glade were located by statistical analysis. Uniformity in fresh snow density throughout the area suggested that inches of snowfall could be compared with runoff. Data on snowfall at 5 precipitation stations in the Golden area were compared with runoff at Golden during 20-year period. Similar statistical methods were used for other stations. Seven new courses were planned on the basis of these statistical analysis. New courses for the Trail and Kootenay River are planned. A location map shows the location of stations, and tables of data and graphs illustrate the procedures.
Keywords: Snow course location, Statistical methods, Water supply forecasting

Accuracy of individual samples in a snow course - Hunter, C.E.; Devore, G.W. (5th Annual Western Interstate Snow Survey Conference, 1937)
Variation in yearly water content of a particular sample point in relation to the water content average of the snow course was obtained for each of several years. Percentages of the mean of each sample for each year was then calculated. These data were tabulated and plotted under 'Scale' for water content and 'Percentage of Mean' for the percentage of the mean water content. The graph gave the relation of water content of each sample to the average of mean of the course for each year. When the percentage of the mean for any sample was widely scattered, the sample was considered unreliable. Unreliable areas were examined to locate the cause. It is believed that more research will result in establishing courses of 10 to 15 reliable sampling points. H.P Boardman presents a discussion of the paper and proposes methods of analysis and graphs for several snow survey courses and detailed reasoning in the text.
Keywords: Snow survey course analysis, Statistical methods

Winter precipitation versus snow survey for forecasting on Skagit River, Washington - Leaver, R. (5th Annual Western Interstate Snow Survey Conference, 1937)
A discussion of a paper on the monthly flow forecast of the Skagit River at Diablo Dam is presented. The monthly precipitation on 1100 sq. mi. of drainage area and the monthly mean inflow into the reservoir over a 25 year period were compared. It is shown that 68.7 percent of the rainfall enters the reservoir in an average year. Also half of the rainfall occurs from October thru December; the runoff is less than 18% during the same period. The difference forms a surplus to be drawn upon during the remaining 9 months. Each year the percentage of normal precipitation for Oct.-March is near to the percentage of normal inflow from April-Sept. The flow of the river for each particular period can be predicted within a mean average of 5% from the 25 year record by summing up the maximum and minimum figures for each month. The value derived by using the snow survey seems questionable since the prediction of increase runoff from snow-reservoir conditions is affected by temperature. Discussion by H.H. Boardman.
Keywords: Statistical analysis, Water supply forecasting

The present status of snow surveying and irrigation water supply forecasting in the west - Marr, J.C. (5th Annual Western Interstate Snow Survey Conference, 1937)
A narrative of ‘The Cooperative Federal-State-Private Snow Survey Program’ is presented. the details of organizing such a program throughout the eleven (11) western states was necessary, not only from a financial standpoint as from the physical impossibility of the small oraganization staff reaching the widely separated snow survey courses. The centralization of data collection and publication by states or river drainage areas, permitted all cooperators and others to profit from all the data collected, and the assessment of probable water supplies for irrigation and water management. Without the cooperation of the U. S. Forest Service, Park Service, Power and Irrigation districts or companies; the U. S. Geological Survey, Weather Bureau, Bureau of Reclamation and Corps of Army Engineers; the snow survey program and water supply forecasting would never had been assembled.
Keywords: Snow survey organization

Frost in the soil a suggested factor affecting forecasts - McLaughlin, W.W. (5th Annual Western Interstate Snow Survey Conference, 1937)
The need for measuring the amount of frost in the soil mantle under the snowpack as well as the water content at key stations through the river basin is brought out as one of the many factors in stream forecasting. This problem is immediately associated with soil temperature and soil moisture at several depths below the soil surface. Measurement of these factors in connection with snow surveying and forecasting is being considered.
Keywords: Soil moisture, Soil temperature

Weight versus melting method for determining density of snow - McNutt, J.J.; Alcorn, W.B. (5th Annual Western Interstate Snow Survey Conference, 1937)
Snow density measurements were made with the weight method, using a Mt. Rose snow sampler, and with the melting method. A comparison shows that density as determined by weight was higher by as much as 3 percent when determined by melting. The disadvantage of the melting method are: (1) difficulty in obtaining an accurate sample of snow at great depths; (2) loss of the snow crust from the sample by breaking; (3) lack of air release, causing some snow of the sample to be blown out; and (4) water wastage during melting and measuring operations. Faulty design of the Mt. Rose sampler is suggested as a possible source of error. The redesign and manufacture of the Standard Snow Survey Sampler cutter with an inside diameter of 1.49812 in from the Mt. Rose cutter of 1.5 in diameter and the New Standard Tubular Scales that are calibrated with test weights at regular intervals would reduce the weight method of determining the density of snow.
Keywords: Snow density measurements

Development of snow surveying in California - Paget, Fred (5th Annual Western Interstate Snow Survey Conference, 1937)
The present water use in California for irrigation, power and municipal purposes depends on reliable information on the amount of water which will be contributed by the mountain snow pack in the spring. The existing program of snow surveys was initiated in 1929. The extent of the California Cooperative Snow Surveys is presented, with 175 active snow courses covering 24 watersheds. Forecasting is based on results of snow surveys conducted in April and assumes that average conditions will prevail during the following months. Forecasts of April 1 are modified and corrections published on May 1 when abnormal precipitation during the early runoff period occurs. The ‘Direct method curve’ used to modify accurately the original estimate is illustrated using the Upper San Joaquin River watershed as an example. The Direct method of forecasting was made possible by the 10 years of existing records on snow courses and runoff, and provided sufficient data to establish a relationship between snow survey data and runoff data with some degree of accuracy, without becoming involved with percent of normals.
Keywords: Snow survey water supply forecasting, Statistical analysis

Luncheon conference and round table presentation of experiences and problems in snow surveying - Parshall, R.L. (5th Annual Western Interstate Snow Survey Conference, 1937)
An informal round-table discussion is presented by several authors. (1) Questions were asked of Mr. H.L. Potts relative to procedures of forecasting runoff from yearly photographs of the snow cover on the watershed. (2) A movie of snow surveying in the High Sierra was shown and commented by George A. Lewis. (3) What are the criteria for 'A Good Snow Course’ was discussed by O.C. Reedy and several other snow survey authorities. (4) Merril Bernard spoke relative to a forthcoming report 'Deficiencies in Hydrologic Research and Data'. He stated that this report could be used for intelligent planning of research projects in the direction of positive results. (5) R.S. Goodridge spoke of snow research project under way in the Ohio Valley in connection with flood control research. An experimental watershed had been chosen and instrumented.
Keywords: Flood control, Snow course analysis, Snow research

Snow course markers - Parshall, R.L. (5th Annual Western Interstate Snow Survey Conference, 1937)
Masonite strips, 2 x 6 inches in size, were tested to evaluate masonite boards as snow course markers. A strip submerged in water for 30 days increased approximately 0.6 inches in thickness but regained normal thickness upon drying. It is concluded that masonite board painted with an enamel base and a liberal coat of linseed oil on the reverse side will provide satisfactory use for more than 20 years exposure in the mountains where wet and cold conditions exist. This material is light in weight and the printing will not be spoiled by rifle bullets as experienced with the metal and baked enamel signs.
Keywords: Snow survey markers

Economic value of snow surveying for the Los Angeles aqueduct - Phillips, J.E. (5th Annual Western Interstate Snow Survey Conference, 1937)
The benefits derived from snow surveys are often difficult to evaluate financially. The City of Los Angeles, Department of Water and Power, shows well planned operations by using snow survey data for reservoir regulation for municipal water supply from the Owens River aqueduct; for requirements of possible pumping operations for supplementary water needs, also for water-spreading operations to build up ground water supplies through irrigation on city owned lands leased to farmers along the upper reaches of the Owens River. Plans for lease rentals and crops to be planted are based on knowledge gained from snow survey data.
Keywords: Economics of municipal water supply, Economics of snow surveys

Snow surveys and runoff forecasting from photographs - Potts, H.L. (5th Annual Western Interstate Snow Survey Conference, 1937)
A series of photographs was taken from the same point of a high range near Hoosier Pass, Colorado, at intervals throughout the year. The percentage of the area covered by snow in each photograph was calculated by superimposing a transparent template on the picture and counting the squares in which snow appeared. The total runoff was calculated on Nov. 1 from the date on which each photograph was taken. Curves for 3 consecutive years were plotted as functions of snow cover and runoff on the same chart. Considerable variation in precipitation was obtained. It is shown that the distance between the 3 curves is approximately directly proportional to the differences in recorded precipitation. The total amount of water which will be available for use is determined by calculating the ratio between total runoff and total diversions at the city intake for an average year.
Keywords: Photography measurement of snowline, Water supply forecasting

Application of snow survey data by the Bureau of Reclamation - Reedy, O.C. (5th Annual Western Interstate Snow Survey Conference, 1937)
Snow survey data are used for forecasting water runoff on watersheds. The Bureau of Reclamation used the data from the Okanogan River Basin in Washington, The Malheur in Oregon, the Boise River Basin in Idaho, and the Jackson Lake and Snake River in Wyoming to forecast the water supply at Boulder Dam, Nevada.
Keywords: Reservoir regulation, Water supply forecasting

Possibilities of commercializing and developing winter sports near Crystal Bay, Tahoe, Nevada - Rhodes, F.L. (5th Annual Western Interstate Snow Survey Conference, 1937)
A report on a reconnaissance of the possibilities of developing a winter sports ski area in the Sierra just west and south of Mt. Rose and sloping into the Lake Tahoe Basin above Crystal Bay on the northeast corner of this lake. Observations were made by two skiers who spent the better part of one winter traveling over the area, cataloguing the snow conditions, depths, temperatures, wind and possible ski trails. Summer exploration indicated that although the area is somewhat isolated the possibility of easy access roads would open up the area to year round activities. The close proximity to Reno, Nevada; Truckee, California and the lake Tahoe resort area would seem to make the area worthwhile considering.
Keywords: Winter sports area development

The Stevens seasonal snow-rain recorder - Rinker, L.E. (5th Annual Western Interstate Snow Survey Conference, 1937)
The Stevens seasonal snow-rain recorder is a hermetically instrument consisting of a gravity-beam balance, sensitive to 0.05 in. of precipitation and with a maximum capacity of 100 in. of equivalent water precipitation. The recorder which requires one setting per year is described and illustrated in photographs. Installation in a timber clearing is recommended or it may be used with a windshield. The recorder positioning-motor is powered by dry or storage batteries, which may be charged with a wind driven generator. Long-term records of cumulative precipitation in the form of snow, rain, or sleet are obtainable. The intensity for any period is determined from the cumulative precipitation graph, as exhibited.A discussion by Dr. J.E. Church questions the possible freezing of storage batteries, and solutions to the cold weather problem.
Keywords: Precipitation gage, Snow gage

Attachment of cutters and couplings; spanner wrenches - Ryan, J.T. (5th Annual Western Interstate Snow Survey Conference, 1937)
Experiments were conducted to develop a cutter joint between duraluminum tub and steel cutter to make a replacement of the cutter possible under field conditions. A threaded bushing provides a simple, positive, and reliable connection but usually requires a special wrench for removal. A soldered joint using aluminum solder produces greater strength and can easily be replaced by heat application. Soldering of couplings is recommended. Two models of a wrench designed to increase leverage and eliminate the probability of the pin being forced out of the hole were tested and found satisfactory. Their overall length is 8.5 in. and will not slip off the joint when in use. Information on aluminum solder and source of supply are included.
Keywords: Snow sampler coupling joints, Snow sampler cutter joints, Snow sampler test results

On the relation of weather and snow reports to winter sports - Stone, R.G. (5th Annual Western Interstate Snow Survey Conference, 1937)
The classification of snow for winter sports have definite bearing on the type of skiing available to winter sports areas. A reporting system is being developed with information being sent to metropolitan areas for release by press and radio. A nomenclature of types of snow surface; fluffy powder, new glazed, wet, sticky, or slushy; hard crust or breakable crust, granular or spring conditions. These types are listed on a form for sending and receiving for uniformity in editing for release. Some attempts are made to standardize the terms for use in the East and New England winter sports areas. In the Alps, scientists, government, and mountain clubs have consistently advocated and fostered the education of skiers and climbers in the matters of rational snow-craft as a means to protection of life and enjoyment of skiing at winter sports areas. In view of the rapid growth of winter sports in the west it is advisable that some standard nomenclature of terms be adopted.
Keywords: Winter sports classification, Winter sports snow conditions

Catch-can measurements meet power forecsting requirements in Bishop-Mono basin - Wills, G. (5th Annual Western Interstate Snow Survey Conference, 1937)
Snow survey measurements of 1935 are compared with actual runoff records for the 1935-36 season for each of the 4 watershed; Bishop, Rush, Leevining, Mill Creeks. A graph shows a comparison of the total runoff on all the watersheds combined with precipitation measured at catch-can stations. Experience and observation have proven that a fair forecast of variable water and KWH can be made from catch-can measurements. The catch station cans are about 5 ft in depth and have a cross section area of 1 sq. foot.
Keywords: Forecast in KWH, Precipitatin gages, Water supply forecasting

The effect ot soil-absorption on snow survey forecasting of streamflow - Boardman, H.P. (4th Annual Western Interstate Snow Survey Conference, 1936)
Snow precipitation producing run-off on the eastern slope of the Central Sierra is described. The total precipitation or absorption losses cannot be quantitatively determined, and soil absorption losses as well as evaporation loss must be considered for large basins. It is believed that soil absorption and other losses are constant under otherwise equal conditions and that the run-off is directly proportional to the amount of winter precipitation. Snow survey and runoff of the Truckee and Tahoe basins are tabulated and discussed for 1921-33. The insertion of pipes in the ground, the recording of fluctuations of the ground water level, and intensified precipitation and temperature studies in high altitudes are recommended.
Keywords: Soil absorption, Statistical analysis, Water supply forecasting

Precipitation-surveys for anticipating water supplies - Burton, H.K.; Alter, J.C. (4th Annual Western Interstate Snow Survey Conference, 1936)
A narrative of the meteorological and hydrological occurrences over the Wasatch Mountains, 25 miles east of Salt Lake City, Utah. Snow melt water from this area furnishes the water supply for Salt Lake City and the surrounding irrigated agricultural areas. The bulk of the water supply occurs during a few weeks during May and June and usually in the form of rushing floods. This period is also when maximum storms, warm weather, and melting of the winter snowpack occurs. Ground water supply does not play an important part. For sufficient year round supplies, reservoir storage is essential. Rain gage measurements and snow survey measurements are used to compute the probable runoff for reservoir management. No data or procedures are presented.
Keywords: Water management

Improvements in snow survey apparatus - Church, J.E. (4th Annual Western Interstate Snow Survey Conference, 1936)
A snow sampler combining the capacity and strength of the Mt. Rose sampler and the lightness of the Utah sampler was ordered by the U.S. Bureau of Agricultural Engineers. Dur-aluminum and steel samplers are evaluated as construction materials for strength, core removal, and ease of sampling. Most of the fundamental features of the Mt. Rose sampler were adopted. Design deviations from both sampler types are listed. The Mt. Rose spring balance is considered superior to the tubular or Utah balance. Designs of a new springless balance and a weighting staff of dur-aluminum for use with the spring balance are described and shown in pictures. Tabulations of types of balance are shown.
Keywords: Snow survey sampling tubes, Snow survey weighing scales

Soil-absorption and its effect on streamflow forecasts in Utah - Clyde, G.D. (4th Annual Western Interstate Snow Survey Conference, 1936)
Basic factors affecting relationships of snow cover to runoff, and in particular, results of quantitative measurements of the moisture absorption from the snow cover are discussed. The annual absorption loss is neither a constant quantity nor a percentage, but a function of the permeability of and the percentage of moisture in, the soil at the start of the melting season, of the water-holding capacity of the soil, and the melting rate of the snow cover. The percentage absorption is higher during years of light snow cover. Soil-moisture determinations under the snow cover at the beginning of the melt period may furnish an absorption correlation factor valuable for use in making streamflow forecasts. Theories advanced are illustrated by data within text analysis.
Keywords: Soil absorption, Soil moisture measurement

The Adirondack snow surveys - Cullings, E.C. (4th Annual Western Interstate Snow Survey Conference, 1936)
The topography and temperature of the 12,000 sq. mi. Adirondack Region in northern New York State is described. The drainage system consists of 12 streams flowing in all directions from the Central Highland. Systematical snow surveys were started about 1926 and are made on Feb. 1, Mar. 1, and about the third week in March of each year. Snow surveying equipment, consisting of snow tube, scale, hook, notebook, and canvas bag, is described in terms of construction and usage. Snow and water depths are tabulated and results plotted on a map at the conclusion of each survey. It is recommended that snow surveying be combined with ground water observations and that correlations between snow, ground water, and streamflow be studied. Instructions to observers on purpose, procedure, equipment, measurement and computation are presented.
Keywords: Snow survey equipment, Snow survey procedures

Lamoille creek basin normals: a case in which extension of normals by comparison with precipitation-data proved more valuable by comparison with another stream - Elges, C. (4th Annual Western Interstate Snow Survey Conference, 1936)
An example is given of extended snow cover normals by comparison with precipitation data for a small basin in Eastern Nevada. The expansion was accomplished by comparing the snow cover and an elevation of 7400 ft on March 1 with Nov.-Feb. precipitation. In this case the expansion from precipitation data yielded better results than could be expected by comparison to the stream flow data of the Humboldt River. Tabulation of data and a graph illustrates the results with detailed text analysis.
Keywords: Snow survey normals, Water supply forecasting

Questionaire and answers on snow survey equipment and methods - Jones, J.E. (4th Annual Western Interstate Snow Survey Conference, 1936)
By virtue of the relatively new science of snow surveying and water supply forecasting, the Western Interstate Snow Survey Conference sent a questionnaire to some 231 offices, engineers, and scientists involved in the study of streamflow from snow melt and related problems. Answers to (6) questions and comments were to be included. I.Field equipment; your preference as to type, style, and material and why. 16 items were listed. II. Snow survey courses; location, No./basin. No. points. III. Water supply forecasting; methods, procedures, justify. IV. Collateral data; variables used, length records. V. Streamflow data; normals, extension procedure, use. VI. Cost of snow surveys; per survey, transportation, equipment, observers, annual budgets.
Keywords: Snow Survey questionnaire

Calculation of normals for use with snow survey data - Lee, C.H. (4th Annual Western Interstate Snow Survey Conference, 1936)
Two principal methods are used to forecast summer run-off from snow survey data: the area method, which gives quantitative results but requires gathering field information and is seldom practical for use at present; and the percentage method, which expresses snow cover for any given time as a percent of the normal and requires stable normal values. A 25-year record is sufficient for stable values in humid regions and a 40- to 5--year record is sufficient for semi-arid and dry regions. It is now generally impractical to compute snow normals for snow-cover data alone.
Keywords: Statistical analysis, Water supply forecasting

Status of coordination and standardization of snow surveying - Marr, J.C. (4th Annual Western Interstate Snow Survey Conference, 1936)
The growth to international importance of snow surveys for streamflow forecasting resulted in some progress but lacks in coordination and standardization of procedures. The Bureau of Agricultural Engineering investigated the possibility of correlating the existing snow surveys and the need for new networks, with emphasis on Calif., Nevada, Utah, Oregon, Wyoming, Colorado, and Idaho. Experience useful for a country-wide water supply forecasts was gained. Equipment to be tested is described. Agreement was reached on the minimum number of snow courses in each important drainage basin, surveying and sketching of snow courses. New courses were laid out in Colorado, Wyoming, and the Snake River drainage basin, and a schedule of measurements wet up. Cooperation with the Forest Service, Park Service and the Bureau of Reclamation, together with the Weather Bureau was arranged, together with other agencies.
Keywords: Snow Survey cooperation, Snow Survey network

Extension of normals by precipitation-data and by comparison with another stream - Parker, G.L. (4th Annual Western Interstate Snow Survey Conference, 1936)
A narrative is presented describing possible procedures for estimating the streamflow NORMALS, (Monthly, Seasonal), for gaging stations with short periods of record. By virtue of the great variation of precipitation in the high altitudes and the valley stations and various orographic effects from basin to basin aspect, there seems to be very little correlation in this procedure of extending runoff normals. There is apparently sound procedures to correlate stream gage stations where characteristics are similar. The soundest procedure is to establish precipitation stations and snow course surveys in the basin and create a reliable record of streamflow and be patient.
Keywords: Normals - streamflow, Water supply forecasting

Snow cover measurements and irrigation water supply forecasting - Marr, J.C. (3rd Annual Western Interstate Snow Survey Conference, 1935)
Snow survey and water supply forecasting programs [were] recently organized under the U. S. Department of Agricultural Engineers, Division of Irrigation Research, under an act of the 74th Congress effective July 1,1935. The paper presents some of the early history of snow surveying in the Western States under the guidance of Dr. J. E. Church. A discussion of the various instruments for measuring snow and weighing the sample to obtain inches of water in the snowpack is presented. Also the plans for Cooperative Program with other Federal and State and private agencies involved with irrigation and the management of water flowing in streams that are largely fed by melting snow. Note: No other meeting was held in 1935.
Keywords: Snow survey cooperative program, Snow survey organizations, Water supply forecasting

Evaporation at high altitudes and latitudes - Church, J.E. (2nd Annual Western Interstate Snow Survey Conference, 1934)
A report of a study dealing with evaporation from snow-fields and tree accumulation beginning in 1910 on Mt. Rose, Nevada, (10,800) and in the Lake Tahoe Basin, 6225 altitude. A description of field equipment and procedures of measurement is presented. Tabulations of hourly and daily data are shown in the 24 tables. Comparisons of data are discussed in the text, together with discussion of troubles and solutions to improve the measurements. The author has included data collected while on the Hobbs Exposition to the Ice Cap of Greenland in 1926. Evaporation from snow surfaces were made at that time and data with discussion of resulting information is also included.
Keywords: Evaporation from snow surface, Evaporation from tree accumulation

Relationship of degree-days above freezing to runoff - Collins, E.H. (2nd Annual Western Interstate Snow Survey Conference, 1934)
Methods of predicting the water supply available at the low-water period in Coeur d’Alene Lake, the storage reservoir for hydro-electric power development on the Spokane River, are assessed. Snow surveys were unsatisfactory because of the low elevation of the drainage area, and the storage rights limiting the retaining of flood waters. Temperature studies indicate that below freezing did not influence runoff, but that temp. above freezing effected snowmelt. The relation between degree days above 32 degF and runoff were computed and plotted against runoff to create a graph for predicting runoff satisfactorily. By using a combination of the summation of degree-days and a summation runoff prior to the date of prediction better results are experienced.A discussion of the paper by Carl Elges and J.E. Church is presented on page 629 (of this same publication).
Keywords: Degree days, Water supply forecasting

Improvements in forecasting the flow of the Humboldt River, Nevada - Elges, C. (2nd Annual Western Interstate Snow Survey Conference, 1934)
A description of the revised system of stream-flow forecasting for the Humboldt River in North Central Nevada is presented. The lack of existing records of the streamflow and snow survey data and other meteorological factors in the Humboldt Mountains has hampered accurate results of forecasting. The isolation of the river basin surrounded by wide expanses of dry desert lands poses a major problem to locate correlation data with streamflow. The gageing stations are far downstream and below many diversions for irrigation that are also not measured. A list of six (6) recommendations for new stations to measure the several factors necessary for better forecasting.
Keywords: Water supply forecasting

Improvements in snow-surveying apparatus - Jones, J.E. (2nd Annual Western Interstate Snow Survey Conference, 1934)
The Utah improvements on the Mt. Rose snow sampler by using duraluminum alloy tubing and a cheaper cutting bit and a tubular scale are described. All improvements were made for lightness, cheapness and back-packing facility. The use of the lighter tubing in constructing the sampler allows for a shorter tubular scale without sacrificing accuracy. Snow survey shelter cabins located strategically near the snow course is recommended for safety of the field parties.A discussion by S.P. Ferguson of Blue Hill Observatory relative to the original design of the Mt. rose sampling equipment is included and his recommendations for the new design of sampling tubes and scales now that duraluminum alloy tubing has become available in the correct sizes, and of equal strength.
Keywords: Snow sampling equipment

Temperature-divergence between valleys and mountains - Sager, G.V. (2nd Annual Western Interstate Snow Survey Conference, 1934)
A study is made to ascertain to what extent the temperature at Reno, Nevada, Elev. 4521, could be taken as indicative of the departure at the nearby mountain stations, thus giving a clue to the probable melting of snow in the mountains, runoff, and snow wastage by evaporation. Mountain stations at Tahoe City -6230; Norden (Donner Summit) -7017; Marlette Lake -8000; all having 24 years of records 1910-1933 were used for the study. Normals were computed and means of departures month by month were tabulated and graphed. A summary in the text indicates that other factors, difficult to measure are involved in a formulas to forecast the snowmelt runoff.
Keywords: Snowmelt runoff, Temperature factors

The Stevens annual snow and rain recorder - Stevens, J.C. (2nd Annual Western Interstate Snow Survey Conference, 1934)
A description of a new automatic rain and snowfall record-gage is presented. (Shown in photograph). This instrument is designed to record a winter season catch of precipitation and print the resulting amounts on a graph. The receptacle has a capacity of 100 inches of precipitation either rain or snow. The receptacle is originally charged with a calcium chloride solution to prevent freezing and an oil film to prevent evaporation. The receptacle is balanced on a weighing frame and the weighing beam is kept in balance by a reversible motor that keeps the weighing ‘Paul’ constantly in balance. The weights are recorded on a weight driven ‘Stevens Type 30’ water-stage recorder. A wind motor provides current and charges batteries. The instrument is designed for isolated locations. The manufacturer; Leupold, Volpel Company, Portland, Oregon. Later years Leupold-Stevens Instrument Company.
Keywords: Precipitation gage