Forecasting the dry‐weather flow of Pond Creek, Oklahoma: A progress report

Pond Creek in west‐central Oklahoma drains an area of 319 sq mi above the gaging station near Fort Cobb, Caddo County. Ground water, contained in the Permian Rush Springs sandstone under water‐table conditions, moves toward the creek at an almost unchanging rate. The discharge of ground water into the creek as dry‐weather flow is modified by evapotranspiration and antecedent overland runoff. Multiple correlations have been computed relating the dry‐weather flow to the water level in a well and to a factor indicative of the rate of evapotranspiration. A method for forecasting the factor indicative of evapotranspiration and one for forecasting the water level in the well during dry weather are given; the result is a method for forecasting the dry‐weather flow of the Creek. Forecasts of dry‐weather flow for seven and 21 days compare favorably with observed flows. The technique may be utilized to extend a forecast for several months.