California's Dependence On Groundwater Reserves Increases; New Reservoir Project Moves Forward

Mar 3, 2015

California’s farms and, increasingly, urban residents will be dependent on groundwater reserves for water supplies as parched conditions continue into a fourth year. Meanwhile, long-term plans to help ease California’s chronic water shortages took another small step forward. 

Hopes for enough rain and snow to break the ongoing drought have gone from doubtful to nearly unfathomable as winter yields week after week of unusually warm and dry weather.

On Friday, authorities with the federal Bureau of Reclamation made a widely expected announcement that little water is available to distribute. 

Agricultural growers holding highly coveted “senior water rights” will likely wind up getting about half of what they are promised while those with junior rights will get no water at all. Municipalities and industrial users were told to expect a quarter of their allotments. State officials meanwhile Monday increased planned deliveries to a fifth of contracted amounts. 

It all adds up to greater dependence on water pumped out of deep underground aquifers. It is unclear exactly how much water lies hidden below the surface or how many wet years would be needed to replenish it. There are also concerns that over-pumping and land subsidence may prevent such underground reservoirs from completely refilling. 

Federal and state officials will continue recalculating allotment figures monthly, but with March already underway and the state’s snowpack at barely a fifth of normal, it’s increasingly hard to imagine conditions improving. Federal officials said a second consecutive year without allocations would be unprecedented. 

Meanwhile, a project that could potentially smooth out some of California’s chronic feast or famine water cycle took another step forward late last week. Congressmen John Garamendi, a Walnut Grove Democrat and Oroville Republican Doug LaMalfa introduced enabling legislation for a new reservoir west of Maxwell in Colusa County.

The proposed dam and reservoir would not block any new rivers to capture water, but would instead use mainly existing canals to divert occasional flood water off the Sacramento.

“Sites reservoir would create water in two ways,” Garamendi said. “First, it’s an off-stream reservoir. So, water would be pumped into it when there are flood flows in the Sacramento River. That water would not be required in the Delta or in San Francisco Bay. So that’s all ‘new’ water. In addition to that, Sites Reservoir allows for flexibility on all of the reservoirs in the Sacramento River system.”

The furthest downstream intake for Sites would be at Moulton Weir, just downstream from the Sacramento’s confluence with Butte Creek, north of Colusa. Garamendi said if all goes according to plan, the reservoir could be completed a decade from now.