It didn’t take long for Weisenberger, general manager of the Banta-Carbona Irrigation District, to confirm that the water level southeast of Tracy was 6 inches below sea level — a near record low, according to Weisenberger.
His assessment was verified by the sound of pump No. 1 in the pump house sucking air.
“This happens when we have a low flow of water in the river and a low tide,” he said. “But usually, we pump several inches above sea level, and now we’re below zero.”
While a rise in the tide would get the pump moving water in a few hours, it is another signal that water in the San Joaquin River east of Tracy is flowing at half the usual volume for this time of year. And more ominously, that low river flow is a warning sign that the real impact of a growing shortage of water could affect many Tracy-area farms a year from now.
“We can get by without any major problems this year — July is our peak month for water deliveries — and major plantings of almond trees in the past several years are actually helping, at least temporarily, since young trees require less water than mature ones.” he said.
Unless there is heavy rain in the valley, and especially a huge snow pack in the Sierra Nevada this coming winter and spring, Weisenberger said 2014 could “be a very rough water year.”
The possibility of a serious water shortage in the 2014 has prompted Weisenberger and the BCID board of directors to send out a letter this week to farmers in the 18,000-acre district, warning of possible water rationing in the coming year.
“We want our growers to be aware that rationing is one of the measures we may have to employ in 2014,” he said. “We will consider all options.”
What many people in agriculture are calling “the water crisis” has been triggered by two dry rainfall and snowfall years, capped off by a record dry spell beginning in January.
The combination has left the Sierra snow pack this year at 17 percent of its normal level.
Although water managers are attempting to retain as much water in reservoirs as possible, the water levels are decreasing to meet often-competing goals for agriculture, water quality, fish and the environment.
New Melones Reservoir on the Stanislaus River, which flows into the San Joaquin River just below the BCID intake, is at 48 percent of capacity and is slowly dropping from releases. It will take a huge snowfall in the coming winter to be replenished.
Despite the New Melones releases, the flow in the San Joaquin River at the Durham Ferry Road Bridge in Vernalis, southeast of Tracy, is currently at 525 cubic feet per second.
“A normal year this time of year, we would have 1,000 cfs in the river,” Weisenberger said. “This year, you can walk across in some places.”
Although Banta-Carbona pumps 90 percent of its water from the San Joaquin River, it still has a contract — this year only 20 percent of full allocation — for water from the Delta-Mendota Canal.
“We are using the DMC water as a reserve cushion this year, but next year our allocation could quite possibility be zero,” Weisenberger said.
He noted that farmers in the district are increasingly implementing water-saving programs, such as buying water-carrying strips of tape below ground for controlled, continuous irrigation.
Closer to Tracy, the 4,800-acre West Side Irrigation District has avoided feeling any major impact of low river flows because of the steady level of Old River, where the district’s pumps are located, reported Dave Kaiser, the district general manager.
“There are temporary rock dams with tidal flaps installed each summer on the Old River, Grant Line Canal and Middle River,” he said. “Although the flow in Old River is less than normal this year, the dams maintain the river levels and control salt-water intrusion.”
West Side’s 20 percent-of-full allocation of Delta Mendota water is being wheeled south of Los Banos to parched irrigation districts relying solely on canal water, he reported.
Like Weisenberger, Kaiser said West Side directors are worried about next year, especially if the drought continues.
“This is feeling a lot like 1976-77, when there was one of the driest periods in recent memory,” he said.
• Contact Sam Matthews at 830-4234 or firstname.lastname@example.org.