Farm water analysts on the west side of the San Joaquin Valley are less than optimistic about the water supply for next summer despite a good snowpack so far this year.
West siders suspect a key Valley reservoir won’t fill up this year, due to water pumping restrictions that protect dying fish in the Sacramento-San Joaquin River Delta.
It’s a familiar refrain. For years, west siders have been making the point about fish protections reducing irrigation deliveries. This year, the farm-water analysts are projecting 40% to 55% of contractual allotments even if the Sierra gets all the snow it usually gets.
The projection comes from the San Luis & Delta-Mendota Water Authority, representing west Valley farmers on the federal Central Valley Project. Among those farmers are Westlands Water District growers.
Here’s how the water delivery works: Water flows from Northern California rivers through the delta to the huge pumps near Tracy in the south delta. The water is pumped south — which is uphill, by the way — to San Luis Reservoir in western Merced County.
To fill San Luis, a steady flow of pumped water continues through the winter. When the water is interrupted, it’s tough to catch up with the loss of pumping.
Salmon and delta smelts sometimes are nearby, so pumping must be slowed or stopped to prevent them from being dragged into the pumps and killed.
Analysts say the restricted pumping in December equates to about a 10% reduction in available farm water supply. The situation may not get any better this month or next month if the fish are still exposed to the danger.
And if the winter suddenly turns dry — as it sometimes does in California — the projection of available water would drop to somewhere between 35% and 40%, according to the authority.