Approximately 80 percent of the irrigated acreage in Stanislaus County requires 32 to 40 inches of irrigation water; without it, major investments in orchards or in dairy facilities and herds are at risk. In 2014, most irrigation district water allocations were 24 inches and will probably be that or less for 2015. During 2014, irrigation districts used extensive groundwater pumping to supplement their surface water supplies and this will continue during 2015.
Annual precipitation during a dry year may add 4 to 7 inches to the irrigation district water allocation of 24 inches. That makes the annual water supply available for crops 28 to 31 inches. The difference will be offset by private groundwater pumping.
Private groundwater pumping is more expensive than the subsidized irrigation water from MID. The immediate future will probably include increasing dependence on groundwater. Under these circumstances, irrigation districts will probably try to increase their groundwater pumping capacity. In fact, this was mentioned in the Feb. 10 MID Board of Directors meeting workshop. There is one alternative that maybe considered, to rent privately owned wells and then sell the water back to the owners at subsidized irrigation rates.
Steve Mohasci, Modesto