RUNOFF MODELLING AND CROP WATER PLANNING GADARWARA WATERSHED IN MADHYA PRADESH

Abstract

Runoff modelling is the non lincarprocess a watershed's response to rainfall.The Soil Conservation Service Curve Number method (SCS-CN, 1972), is widely used for the estimation of direct runoff for a given rainfall event from small agricultural watersheds. There are scveral approaches to estimate runoff in ungauged watersheds. Many methods are used to estimate the runoff from a watershed. The curve number method, also known as the hydrological soil cover complex method, is a versatile and widely used procedure for runoff estimation. This study was carried out for Gadarwara catchment located in Narsinghpur District of Madhya Pradesh. Soil map and land use maps were generated in GIS (Geographical Information System) environment. Remote sensing and GIS is very reliable technique for the preparation of most of the input data required by the SCS curve number model The SCS-CN versatile model is used for the 10 year data for estimation of the Surface Runoff. The Calibration used for 3 year data and Validation used for 7 year data of the Watershed. The resulting efficiency of modified SCS-CN model is 76.65% and 70.08% respectively. The Runoff is used for the crop planning for the Gadarwara watershed. The crop planning is performed using the linear programming in Lingo software. The linear analytical model provides near optimal solution due to the approximation involved in Ii nearising complex natural phenomena. Linear Programming specifies target for irrigation which are further modified by simulation. Linear Programming model optimized the crop areas for four different suitably devised cropping patterns which could be proposed. The four optimal annual irrigation requirements from L.P. model were used as the first approximation of the design variable for simulation. Average flows have been used in the L.P. model whereas continuous monthly intlow series have been used in simulation studied.