As part of a district wide conservation and energy management program, irrigation systems at 155 district sites have been installed or upgraded to operate on an Irrigation Management Control System (IMCS). The IMCS provides 24-hour monitoring and control of scheduled and unscheduled water flow at district sites. A central control unit calculates daily irrigation application schedules based on data from the district's weather station and information about plant types, evaporation rates, and other variables. These steps significantly reduce water use by replacing only the water used by the plant material and lost to evaporation.

In the picture above, plants at Bay Point are receiving the correct amount of irrigation as calculated by the IMCS.

With the IMCS and an efficient, proactive management program, SDUSD has realized a water cost savings of 45 percent annually over the last five years. On average, the district has saved 97 million gallons of irrigation water worth $380,000 per year.

Although water savings through efficient irrigation scheduling is the major benefit of the IMCS, as an ideal environmental management tool it also provides several additional direct and indirect cost savings. Other benefits the district has received from the IMCS include:

An Irrigation Control System Specialist (ICSS), manipulating the individual irrigation schedules from a central IMCS computer, eliminates the need for manual adjustments at individual site controllers.

Currently, the District maintains 320 controllers operating 8500 individual irrigation stations. Using the IMCS, schedule changes can be performed in minutes, and systems can be shut down in seconds. Adding up the time spent visiting each controller to make schedule adjustments and the drive time between sites, it could take a single individual 21 working days to accomplish these tasks manually.

One of the most troubling (and expensive) losses of water is a system leak. Without an IMCS, a leak that occurs underground could take several months or even years to detect. Leaks of 5-25 gallons per hour may go undetected altogether but result in a substantial dollar loss over time. Automatic system flow monitoring detects leaks in just hours, saving potentially huge amounts of water and money.

Use of fertilizers and other soil additives or nutrients can be reduced through better irrigation management. Proper watering means less leaching and runoff, which reduces the need for additional fertilization applications. In turn, good plant health reduces pest infestation and disease. Liquid fertilizers can be applied directly through the irrigation system, in concert with the central control system, eliminating most or all manual fertilizer application costs.

The IMCS monitors water flow on a minute-by-minute basis, including nonscheduled manual use of the system. The system can compare actual usage to a water budget and fine-tune the irrigation system to obtain optimum water savings.

Broken sprinkler pipe and heads can result in costly soil erosion, wasted water, and more importantly, a public liability of incalculable cost. The IMCS automatically shuts down portions of a system when excess water flow is detected, and warns system operators that a problem exists. A traditional maintenance crew may take several days to notice these breakages.

For more information on the irrigation central control system go to: