The Use of the Compartmented Reservoir in Water Harvesting Agrisystems

Abstract

Runoff farming under most climatic conditions and soil types requires some type of efficient surface water storage in order to maintain production during dry years. The combination of a treated catchment feeding runoff water to a planted area coupled with surface storage is defined as a water harvesting agrisystem. Surface storage in order to be efficient requires evaporation control and in most cases seepage control. Various methods are available for economical seepage control but the cost of the currently used evaporation control methods are high enough to preclude their use for growing conventional crops using water harvesting agrisystems. A promising solution is the use of the compartmented reservoir to reduce evaporation loss. This method utilizes systematic pumping and removal of water from storage to keep water concentrated in the smallest number of compartments built within the typical shallow reservoir. The paper discusses the construction and design of several of these systems. It describes the use of the Compartmented Reservoir Optimization Program (CROP-76) developed in 1976 and improved in 1978 (CROP-78).