OPTIMAL DESIGN OF DRAINS FOR AGRICULTURAL LAND

Abstract

^,$ cr- st iDlays a key role in the economic feasibility of a. drainage project, the optimal analysis in respect of placement of drains is very necessary, It is found from the study t;toptimal solution occurs for a single level drainage system and a bialevel drainage system is not economical due tQ high cost of pipes For a single level drainage system, there is a particular spacing of drain (and the correspond-ing height from the impervious layer) for which the cost of drainage system is minimum'. If optimization procedure is not adopted, the cost of the drainage system may be much on the higher side than the minimum cost. The cost function is more sensitive to the level of alternate drains in comparison to their spacing: ' The optimal cost of drainage system also depends upon the value of recharge/hydraulic conductivity. Further, if the land has become waterlogged due to external source, the drain should be located as near as possible to the impervious layer and nearer to the high es ter table side to have maximum benefit..