The needs and availability analysis of irrigation water of Way Wayah Irrigation Area

Abstract

Optimization of agricultural land is an effort to mprove and increase land support capacity, in such a way become more productive farmland. The Local Government of Pringsewu Regency planned to develop irrigation network by utilizing Way Wayah river. This study aims to design irrigation area in Way Wayah and to analyse water availability of Way Wayah river and water need of the planned irrigation area. Irrigation network design includes analysis of determining the location of the weir, so that it can be estimated the area of designed paddy field, the catchment area as well as the availability of water resources. Analysis includes spatial analysis using Geographical Information System, hydrologic analysis for water availability and Penman method for irrigation water need. The results show that (1) the planned weir will be located in Giri Tunggal with catchment area of 7,238.9 ha, the area of total paddy rice fields (existing and planned paddy rice fields) is 960.46 ha; (2) The need for water are 6196.88 m3 ha-1 season-1 and 6556.96 m3 ha-1 season-1 for planting seasons 1 and 2 respectively. Water availability is sufficient during preparation and planting periods