"Hydrology is the science treating of water from the time it hits the earth until it leaves the earth. This never ending movement of water is called the "hydrologic cycle" and is best summarized graphically. The hydrologist is primarily concerned with rainfall, runoff and evaporation. One of the basic aims of the science is to compute the surface runoff from any rain on a given area. Surface runoff is here considered as that water which reaches the channels without penetrating the ground, plus subsurface storm flow. Subsurface storm flow is slower than surface runoff but faster than ground water flow. There is no clear division between surface runoff and subsurface flow and the two are considered as surface runoff in this study.
"A problem of prime importance to the river forecaster is that of estimating what portion of the rain falling during a storm will be absorbed by the soil and what portion will run off the land surface, thus contributing to flood flows. This problem is directly related to the moisture content of the soil and, consequently, observations of soil moisture should be of direct benefit in flood forecasting. Moreover, soil-moisture data are a valuable adjunct to the climatological records which for many years have been collected by the Weather Bureau.”
Small area drainage basins are particularly important in highway engineering. A few years ago 51 percent of all funds spent for State-Federal water way structures were for spans of 20 feet or less. “The hydrologic data available for the design of small drainage structures is pitifully small when one considers the investment that is being made in such structures." In recent years the U.S. Geological Survey, Water Resources Division has directed considerable work toward the collection of basic data on small drainage areas. This information should prove invaluable to state where these studies are going on with the present trend in increased highway construction. Any additional information on the rainfall runoff relation of a small watershed would be of practical value because of the short periods of record of existing data and in many cases the complete absence of data.
There are many variables in the rainfall runoff relationship for any drainage basin; total precipitation, rate of precipitation, soil moisture, surface slope, type of vegetation, type of soil, distribution of precipitation, temperature, humidity, season of the year, etc. The many variables become more complex as the size of the drainage area is increased. If the drainage area is decreased, the variables become less complex but an additional error is introduced in expanding the relationships to an area of larger size for practical application.
This thesis is directed toward the collection of basic data on soil moisture in relation to runoff. A natural drainage basin of 0.227 square miles (measured by transit stadia survey) was selected for this study"--Introduction, pages 2-4.
Gevecker, Vernon A. C., 1909-1992
Civil, Architectural and Environmental Engineering
M.S. in Civil Engineering
Missouri School of Mines and Metallurgy
vi, 78 pages
© 1953 John William Clark, Jr., All rights reserved.
Thesis - Open Access
Runoff -- Mathematical models
Rain and rainfall -- Mathematical models
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Clark, John William Jr., "Runoff and soil moisture" (1953). Masters Theses. 2209.