Journal of Irrigation and Drainage Engineering

A 0.20‐ha (0.5‐acre) recharge basin was tested for conserving storm runoff that collected in a 16‐ha (40‐acre) playa in the Southern High Plains. The basin was constructed by removing 1.2 m (4 ft) of soil to expose permeable sediments. Turbid water was pumped from the playa to the basin during eight tests over a 7‐yr interval. Average recharge rate during 187 days of flooding was 0.373 m/d (1.22 ft/day). After three recharge tests during the first year, no maintenance was done to the basin bottom. Our research showed that recharge basins could be an effective technique for partially replenishing the depleted Ogallala Aquifer.

Irrigation uniformities are examined for six assumed statistical distributions of depth of water infiltrated. Christiansen's uniformity (UC) and the lower quarter distribution uniformity (DU) are related analytically to the coefficient of variability (CV) in each case. The distributions chosen are the normal, log normal, uniform, a specialized power, beta and gamma distributions. In all cases studied, for CV values of less than 25%, approximate forms of UC and DU were found valid. Three examples are given using the specialized power and beta distribution. It is demonstrated that the specialized power function is exact for level basin irrigation provided the surface water advance is proportional to a power of time and the intake rate everywhere has approached a constant value before recession.

Closed form algebraic solutions are presented for recession and runoff integrals. These integrals first appeared in a paper on border irrigation by Strelkoff who solved them numerically. Later, Reddy presented a numerical solution which was proclaimed to be more economical in terms of computing time. Algebraic solution is more elegant and straight-forward.