In late May when the state of California shut off the pumps transferring water from Northern California to Southern California to protect an endangered minnow, the Department of Water Resources said the anticipated 7-10 day shutdown would have “no impact” on 23 million Californians and millions of acres of farmland relying on that water.

When more than 100 Westlands Water District farmers met 13 days later, they compared that “no impact” to the January freeze that caused $800 million in losses to the state’s citrus industry.

Fortunately, at that Westlands meeting the farmer-friendly Bureau of Reclamation announced it had, the evening before, turned on two of the six pumps at its Delta pumping station, averting a major disaster in the 600,000-acre district where about 15,000 acres of grapes are planted.

The pumps sent water south to the San Luis Reservoir, the 2 million acre feet-capacity lake near Los Banos that is a holding lake for water from both the state and federal water projects.

After the pumps were shut off, the lake began dropping 2 feet per day as farmers and cities continued to use the water. It quickly approached a critical level, where the bureau could have been forced to stop withdrawals to protect the huge earthen dam from sloughing off.

The state pumps shutdown, which lasted well beyond the 10 days, was to protect the juvenile stage of the Delta smelt, a non-native California fish that is classified as endangered.

Westlands had only a 25-day supply of water in the reservoir when Central Valley Water Project pumps were turned on again. The state pumps were not turned on when the bureau turned on its pumping station.

Both had the authority to re-start the movement of water, and both had access to the same biological information regarding the smelt population near the pumps.

With the state shutdown, Westlands growers were sent scrambling for water. Many were counting on about 120,000 acre feet of surplus water the district was purchasing to supplement the 50 percent allocation each received, and the shutdown put that water in jeopardy for timely use this season.

Last year the district received its full allotment, but this season a below-normal Sierra snow pack resulted in reduced deliveries.

The pump shutdown happened as the valley began its first heat wave of the season when temperatures reached 100 degrees for the first time and sent irrigation demands soaring.

Growers began abandoning row crops like cotton to preserve water available in San Luis for permanent crops like grapes. About 20 percent of the district is in permanent crops.

There was a limited supply of water put up for auction after the shutdown. One auction for 100-acre-feet netted the seller $510 per acre, roughly four times the average cost of Westlands surface of groundwater.

While the bureau’s decision to turn on the pumps averted a major crisis — a total shutdown of the largest irrigation district in the nation — the farmers were not out of the woods. It takes time to move water to the reservoir and into the fields.

There was also a chance the tiny minnow could re-appear near the pumps, although that seemed unlikely with water temperatures rising to lethal levels for Delta smelt.

Just in case, Westlands developed voluntary and mandatory water curtailment plans should the situation worsen.

A bureau spokesman predicted the smelt-driven crisis would be over soon, and all pumps would be back on by July 1. Hopefully, that will be in time to deliver irrigation water to finish the grape crop in Westlands.