TY - Generic T1 - The 1948 flood of the Columbia river an analysis of its cause and its importance in operation planning T2 - 58th Annual Western Snow Conference Y1 - 1990 A1 - Speers, D.D. A1 - Barcellos, D.J. A1 - Wortman, R.T. KW - Floods, Reservoir Operations, Snowmelt modeling, Water supply forecasting AB - The 1948 flood on the Columbia River has significant implications to the Corps of Engineers in the formulation of flood control criteria for reservoirs in the Columbia basin, because it had a large runoff forecast error - in which spring runoff was significantly greater than predicted by snow and winter precipitation indices. An analysis was made of the hydrometeorology of this event, including the magnitude of the snowpack, magnitude and distribution of spring rainfall, and temperatures. Using the SSAARR hydrologic model these factors were simulated in various combinations and compared with other years. The conclusions were that no single factor that produced the flood was extremely rare, but their combination was relatively unique. The event could be considered more rare than its nominal recurrence interval of approximately 50 years computed from streamflow records. JF - 58th Annual Western Snow Conference T3 - Proceedings of the 58th Annual Western Snow Conference PB - Western Snow Conference CY - Sacramento, California UR - sites/westernsnowconference.org/PDFs/1990Speers.pdf ER - TY - Generic T1 - Runoff forecasting for reservoir operations - the past and the future T2 - 50th Annual Western Snow Conference Y1 - 1982 A1 - Speers, D.D. A1 - Versteeg, J.D. KW - Models - snowmelt, Water Supply Forecasting AB - Two techniques of long range water supply forecasting are compared for the Detroit Dam watershed, a 'rain-on-snow' basin in Western Oregon. A traditional multiple regression procedure has been employed to forecast spring runoff, which is of operational interest for refill of the reservoir. The second approach involves the use of a continuous, conceptual hydrologic model, the SSARR model. Comparing an 11 year test period, a similar degree of accuracy was achieved with each type of forecast. The paper illustrates, however, that the use of a hydrologic model can provide advantages over the statistical forcast, namely: (1) improved accuracy in a real-time setting through continuous adjustments of model parameters to observed conditions; (2) a greater variety of forecast products, including short term flood forecasts and probabalistic estimates incorporating a reservoir model. JF - 50th Annual Western Snow Conference T3 - Proceedings of the 50th Annual Western Snow Conference PB - Western Snow Conference CY - Reno, Nevada UR - sites/westernsnowconference.org/PDFs/1982Speers.pdf ER - TY - Generic T1 - CROHMS - an example of successful interagency coordination in data collection T2 - 47th Annual Western Snow Conference Y1 - 1979 A1 - Speers, D.D. KW - Computer operations, Computer procedures, Telemetering - hydrologic data AB - In October 1978 the central computer facility for the Columbia River Operational Hydromet Management System (CROHMS) was placed into operation, thus marking the completion of 10 years of coordination between agencies of the Pacific Northwest in developing a shared data collection system. The CROHMS system consists of a number of automated remote data collection networks, under ownership and operational responsibility of several federal agencies, including the SCS SNOTEL System. Data being collected include snow water equivalent, precipitation, streamflow, and operating data from dams. Data from network controllers are periodically relayed to the CROHMS Central Facility, an extensive data bank in portland, where it is validated, stored, and made available to interagency users on a near 'real-time' basis. Basic policies for the interagency coordination were established by a Memorandum of Understanding, signed in 1970, and implementation has been carried out through the Hydromet Data Committee of the Columbia River Water Management Group. JF - 47th Annual Western Snow Conference T3 - Proceedings of the 47th Annual Western Snow Conference PB - Western Snow Conference CY - Sparks, Nevada UR - sites/westernsnowconference.org/PDFs/1979Speers.pdf ER - TY - Generic T1 - The application of snowmelt forecasting to combat Columbia River nitrogen supersaturation problem T2 - 40th Annual Western Snow Conference Y1 - 1972 A1 - Speers, D.D. KW - Model, Reservoir regulation, Runoff, Simulation, Snowmelt AB - The problem of nitrogen supersaturation on the Columbia River which is alleged to have resulted in severe fisheries losses, is discussed. The cause of nitrogen supersaturation and its effect on fish are reviewed, and several structural solutions to the problem are presented. An effective means in reducing the problem lies in the regulation of upstream reservoirs, and snowmelt forecasting plays an important role in this regulation. Two types of forecasts are utilized, volumetric forecasts determined by multiple regression procedures, and daily simulation of runoff using the SSARR computer model. These procedures are briefly described and examples of their application in combating the nitrogen supersaturation problem are given. JF - 40th Annual Western Snow Conference T3 - Proceedings of the 40th Annual Western Snow Conference PB - Western Snow Conference CY - Phoenix, Arizona UR - sites/westernsnowconference.org/PDFs/1972Speers.pdf ER -