By Ron McNicoll
The Department of Water Resources’ recent snow gauge report has confirmed what many Californians suspected — this is a dry year for the state’s snow melt water. That fact will impact water agencies throughout the state.
At Zone 7 Water Agency, the staff and board are ready for it. The agency creates a report every five years to notify the public whether Zone 7 will have enough water to meet demands over the following five years. This year’s version will account for 2020 through 2024. The board was scheduled to discuss the version at its regular meeting May 20, with a virtual public hearing set for June.
Much of Zone 7’s water comes from Lake Oroville, which with its dam, provides the major source of water for the State Water Project (SWP). As of March 31, the lake was measured at 53% of average level and 65% of capacity.
In the broader statewide picture, a survey taken April 30 at 99 electronically reporting monitoring stations in the Sierra showed 53% of average snowfall, the 11th driest in 71 years of record keeping.
By contrast, the average snow measured last year at the Phillips station at South Lake Tahoe was recorded at 188%, one of the highest levels in recent years. There is plenty of water left from last year to serve Zone 7, caught by reservoirs, both in the Valley and at two water storage districts in the southern Central Valley, as well as in the Valley’s underground water basin.
Zone 7 assumes that, from 2022 through 2024, snowfall levels will be close to normal, so the prospects look good for the entire five-year period, according to the report’s draft. Looking at previous records, Zone 7 is confident there will be near-normal years of snow melt following one dry year, despite climate change. If it does not turn out that way, Zone 7 will have various water and storage agencies from which it can buy more water.
In June 2017, Zone 7 approved a policy of conserving a minimum of 10% of its total demand to help serve as a back-up. However, actual conservation figures have reached 18%, because customers have been conserving at a higher rate than the minimum, said Zone 7 General Manager Valerie Pryor. A high amount of the voluntary cutbacks has come from reductions in landscape watering.
Zone 7 will receive an allotment from the SWP of only 15% in “new” water in the next calendar year, compared to 49% in 2016, a level published in the report. The lowest allocation in the driest year would amount to 10%, the report indicated.
Zone 7 will be diverting some of its stored supplies to usage in the coming calendar year and picking up more water from such places as the Semitropic Groundwater Bank in Kern County. If 2021 and 2022 turn out to be critically dry years — not the normal years the agency predicts — Zone 7 would seek more transfers from other districts to meet demands.