Runoff from rain and snow

TitleRunoff from rain and snow
Publication TypeConference Proceedings
Year of Conference1947
AuthorsPiper, A. M.
Conference Name15th Annual Western Interstate Snow Survey Conference
Series TitleProceedings of the 15th Annual Western Interstate Snow Survey Conference
Date PublishedApril 1947
PublisherAmerican Geophysical Union, Transactions, Part IV:
Conference LocationPortland, Oregon
KeywordsElectric power, Hydrology groundwater

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.