IID/MWD water conservation program - improved irrigation water management through system automation

Abstract

Imperial Irrigation District (IID) services 450,000 acres in Imperial Valley, California, USA. The sole source of supply is the Colorado River. Imperial Darn diverts water from the Colorado River into the All American Canal (AAC) and subsequently into three main canals. Each main canal is approximately 40 miles in length and can divert 1,200 to 2,200 cfs. Lateral canals are then serviced by the main canals. There are 240 laterals that vary in length from 1 to 10 miles and from 40 to 160 cfs in capacity. Farm deliveries are made through laterals via 5,500 individual user gates. Each has a 20 cfs minimum capacity. On average each delivery services 80 acre parcels. Based on operational considerations, the geographic distribution of control sites, the high inertia of the system and the harsh desert environment a distributed control design was implemented. Commercially available industrial control components were integrated into a SCADA system in a non-traditional manner. Three subsystems were developed; field site automation, communication network, water control center. The level of automation implemented at field sites allows more flexible main canal operation. This allowed the various projects developed under the IID/MWD Water Conservation Agreement to be optimally managed and have water savings verified.