Southern San Joaquin Valley Rivers are running at near historic lows — again.
In fact, the Bakersfield City Council passed a resolution Wednesday officially declaring the Kern River as running at only 17% of normal, it’s second driest year since record keeping began in 1893.
The driest year on record was 2015, the worst year of the 2012-2016 drought.
The resolution notes the river is so low this year, the city won’t have any “excess” water to sell to local agricultural irrigation districts. This is the first time the City Water Resources Department has made such a resolution.
“They know there’s a lot of attention and concern about water, so the department wanted to make sure the public and the City Council are aware of the situation and what the department is doing to make sure the city has a reliable water supply,” said Colin Pearce, Bakersfield’s water attorney.
In that vein, Water Resources also made a deal with Kern Delta Water District in late spring to keep enough water in the river to supply the northeast water treatment plant, which takes water directly off the Kern River.
That plant, owned by Cal Water, serves thousands of homes and businesses in northeast Bakersfield and came uncomfortably close to going dry back in 2015 when the Kern River dropped to 11% of its normal flow.
City and Cal Water officials had to scramble back then to exchange city-owned water in other areas for river water through Kern Delta to keep taps flowing.
Officials weren’t taking any chances this year.
In early May, when it was apparent there would be no more snow in the Sierra Nevadas and the parched forest ground was sucking up what little runoff there was, Bakersfield Water Resources again reached out to Kern Delta, according to General Manager Steve Teglia.
The ag district has been feeding its Kern River water to the treatment plant since about mid-May, he said.
“We’re doing an operational exchange where we’re allowing our water to stay in the river for the city and they’re delivering a like amount to Arvin-Edison Water Storage District on our behalf,” Teglia said.
Though this year is not quite as dry overall as 2015 was, Teglia said, in some ways, the river’s flow is actually worse this year.
That’s because there were intermittent thunderstorms over the Kern River watershed in 2015 that boosted its flows at least occasionally. This year has just been dry and drier, Teglia said.
Rivers up the valley are all experiencing the same dry conditions.
The Kaweah River is at 16% of normal for this time of year; the Tule River is 15.6% of normal and the Kings River was running at only 10% of its average flow on July 12.
And as rivers go dry and imported water is short, water tables are dropping.
While most agricultural districts and even new groundwater sustainability agencies formed under the state’s new Sustainable Groundwater Management Act only check water tables twice a year, in spring and fall, some water districts keep monthly tabs.
Rosedale-Rio Bravo Water Storage district, which covers lands northeast of Bakersfield, checks 42 wells throughout its area. About half of those are in or near water banks so water levels in those wells fluctuate significantly.
Of the 20 domestic and individual ag wells, water levels have dropped about 5.15 feet, on average, since the beginning of the year.
The Kern County Water Agency also checks water levels in a host of wells throughout Kern County. Some are already below their 2015 levels. And most show a steady downward trajectory even after flush water years.
It’s the same story all over the valley. Groundwater maps on the Department of Water Resource’s SGMA online portal show water levels in a majority of the wells that are monitored by the state in the San Joaquin Valley have dropped more than 10 feet from spring 2010 to spring 2020.
“The problem with groundwater rebounding is it takes a lot longer than surface water,” said Helen Dahlke, an associate professor of integrated hydrologic science at UC Davis who’s been studying groundwater recharge models.
Reservoirs will fill to the brim in good water years, but groundwater takes its time, she explained.
Even after the last drought when farmers, water districts and even valley cities began to recharge groundwater in earnest, “it will take time before we can make a dip in our overdraft,” Dahlke said.
Meanwhile, the only way to stem the drop in groundwater is to idle the land, she said.
“I say that as a scientist. But for farmers that’s a very difficult decision.”