State to audit ‘broken’ water supply forecast

The Joint Legislative Audit Committee has approved Assemblymember Adam Gray’s (D-Merced) request to audit California’s water operations after the state overestimated the forecast and prematurely released 700,000 acre-feet of water last year.

“Errors on this scale have real and measurable consequences,” said Gray. “The managers of the largest local, state, and federal reservoirs use this information to determine when to let water accumulate and when to let water out to make room for the coming snowmelt. Growers use the information to predict how much water they can expect for their farms and how many acres they can afford to plant. The estimates are used to inform everything from flood control to power generation and water quality standards.”

The audit, which is expected to take six to seven months to complete, will shine a light on the Department of Water Resources and the State Water Resources Control Board and their failures to accurately forecast California’s water supply and the impacts of those flawed forecasts on reservoir operations and the allocation of water to rights holders.

Gray pointed out that other public agencies – including local irrigation districts and a federal agency whose duties include calculating how much water is in the annual snowpack – did not make similar mistakes.

“No one expects DWR or any of these organizations to get the number exactly right,” said Gray. “But when the state’s best forecasts are demonstrably inferior to local and federal forecasts we need to ask why, and we need to fix the problems as soon as possible. Until we understand what has gone wrong with the agencies charged with managing California’s water, we cannot understand how to fix the problem.