Despite a winter that’s provided disappointing rainfall numbers, Turlock Irrigation District customers are still enjoying the benefits of last year’s record-setting rainfall with a 48-inch irrigation cap for the 2018 season set to begin Thursday.
Growers took advantage of a 48-inch allotment last year as the 2017 irrigation season began in the midst of a historic precipitation year, which at the time had received over 200 percent of the region’s historical average for rainfall with 51.4 inches. It was declared the wettest year on record, followed by 1983 and 1969.
This year, however, there has been little rain in the area. TID originally considered entering into an early irrigation period in January after the Tuolumne River Watershed had accumulated just 7.76 inches of precipitation since September and .72 inches total that month, but a small-yet-welcome rush of rain quickly put a stop to the plan.
The area has received even less than that in February – .58 inches – and the 12.3 total inches of rain that the watershed has now received since September is just 50.1 percent of average.
Because of the drier-than-normal conditions, TID Water Distribution Department Manager Mike Kavarian announced on Feb. 6 that the 2018 irrigation season would begin at the beginning of March if conditions persisted. Last year, the season didn’t begin until March 30, but that same year’s ample rainfall filled Don Pedro enough to provide 48 inches for farmers again this year.
Turlock did receive rain this week and it could continue to rain through Sunday in areas of the district, providing about four to five inches of precipitation in the watershed, said TID Utility Analyst Jason Carkeet. Even with the rain, which Carkeet described as a “March miracle” at Tuesday’s Board of Directors meeting, irrigation season will still begin March 1, said Kavarian. The TID Water Call Center will open Wednesday.
“The forecast for the next 16 days is three to seven inches in the watershed, but that doesn’t translate into rain in the Valley or enough for us to push anything back,” said Kavarian. “We’d have to have pretty substantial downpours.”
In addition to the 48 inches of surface water that will be available this season, growers will also have the opportunity to take advantage of supplemental replenishment water at $15 and $20 per acre foot.
Director Michael Frantz questioned if it was a good idea to provide extra water for farmers during the uncertainty of a dry year, but Kavarian pointed out that a majority of growers who would use replenishment water could pull ground water from their own wells if necessary.
“We’re talking 300 to 500 parcels – it’s really nothing substantial, and a majority have access to wells,” said Kavarian. “We’d rather them use gravity water from above ground than ground water from their wells.”
This week’s rainfall is welcome by TID, added Kavarian, as it will bring about a slower start to the irrigation season – a plus for a water management department that has new staff and several vacancies. The four to five inches of precipitation should decrease the irrigation flows by up to 1,000 cfs, he said.
“Even if it rains, people are going to want to irrigate,” said Kavarian. “It’s better that we start off slow… this is a good way to start.”