groundwater

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New Bill Would Make Confidential Groundwater Info Public

Documents include details on depth and location of wells in California

Sasha Khokha/KQED

A well on a farm in the Central Valley. Groundwater accounts for 30-to-40 percent of all water used in California.

[POST UPDATED, 4/3, 5:04pm]

It’s no secret that with several recent years of drought, California’s groundwater supplies have come under increasing strain. But Dennis O’Connor, a water consultant with the State Senate Natural Resources and Water committee, wants to rewrite an arcane piece of California water law that, for decades, has kept documents containing information on the state’s groundwater resources under wraps.

The documents O’Connor wants released to the public are called well completion reports, or “well logs” – technical documents filed by well drillers with the state. Under California water law, well logs are confidential, accessible only by individuals in state agencies or those who meet special criteria.

“These logs are rich sources of information. The data can help you connect the dots and create a three-dimensional picture of what’s going on underground,” O’Connor told me. Logs contain data on the depth, location and geology of the sites as well as engineering details such as the kind of casing used and the angle of drilling.

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A Watered-down Bond for Water System Improvements?

CA Senate President Pro Tem tells water conference $11 billion is too much 

Kimberly Ayers

Is the 2012 water bond heading for the drain?

“There are two subjects water people least want to talk about: politics and money,” said the former head of the Los Angeles Department of Water and Power, David Nahai. He was speaking at the “Future of Water in Southern California” conference on a dry and windy Friday, here in the City of Angels. And those two were the uncomfortable topics State Senate President Pro Tem Darrell Steinberg (D-Sacramento) talked about in his lunch hour keynote.

“Everybody asks ‘what’s gonna happen with the bond?’ I don’t know,” Steinberg countered, to modest chuckles.

Sponsored by UCLA’s Luskin School of Public Affairs, the conference was generously sprinkled with Southland water and sanitation district staff. They’d just spent the morning presenting new ideas for water “banking,” and new technologies for advanced recycling, and Steinberg knew the idea of less money would not wash down well with the noontime pasta salad and sandwiches. In fact, a proposal to cut 25% from each project in the water bond measure even failed an Assembly committee vote on Jan. 10th. Continue reading

The Central Valley’s Giant Sucking Sound

Studies reveal huge water withdrawals from aquifers under California’s Central Valley

The New York Times this weekend published a story and useful graphic describing new findings on the intensity of groundwater pumping in California’s San Joaquin Valley.

One eye-opening note from Felicity Barringer’s article:

“…the total loss of groundwater from the Sacramento and San Joaquin River basins in California’s Central Valley from 2003 to 2010 was just under 16.5 million acre-feet — approximately the volume of the Lower Colorado River reservoir, Lake Mead, when it is full.”

Lake Mead is the nation’s largest man-made reservoir (and has not been full for some time).

The research, by scientists at a Massachusetts arm of the Stockholm Environment Institute, includes projections for water supply and demand in California and the Southwest. The article points out that about a third of Californians’ total water use is groundwater.

California Losing Groundwater Rapidly

Nearly lost amid the three-ring circus of Copenhagen coverage is the annual gathering in San Francisco of the American Geophysical Union. We’re doing our best to staff selected sessions there. Climate Watch contributor Lauren Sommer was there for some grim new research on groundwater in the Central Valley.

California’s Central Valley has lost nearly enough water in the past six years to fill Lake Mead, according to NASA scientists presenting at the American Geophysical Union Conference in San Francisco this week. Nearly two-thirds of that loss–20.3 cubic kilometers of water–is from groundwater depletion.

With the recent drought, groundwater has been an important water source for California’s Central Valley agriculture, but getting a picture of that water use hasn’t been easy. Water districts haven’t been required to report groundwater pumping in their areas. That’s something the recent Delta overhaul package of legislation now requires, but according to Jay Famiglietti of UC Irvine, the records to date aren’t very complete. Wells are sparse and the measurements have been sporadic.

The majority of the water loss since 2003 has been focused in the San Joaquin Basin at the southern end of the Central Valley, which is losing 3.5 cubic kilometers of water each year. The bulk of that loss is the result of groundwater depletion.

Famiglietti says this is due to a “triple threat” in California.  First came the drought, then decreased water allocation and more groundwater pumping. Finally, with less surface water, the groundwater aquifers have a reduced opportunity to recharge. Famiglietti says it’s clear that California is using groundwater at an unsustainable rate, which “poses significant threats to food production in US and the California economy.”

Groundwater basins in the Central Valley. Image: NASA

Groundwater basins in the Central Valley. Image: NASA

This large-scale picture of California’s groundwater comes from NASA’s Grace project. Twin satellites orbiting the Earth detect changes in the gravitational field, caused by the movement of water. Those satellite measurements act like a“scale at the bottom of the ocean weighing how much water is in each of these spots,” according to NASA’s Michael Watkins.  They also detect changes in snow, surface water and soil moisture.

The Grace project, though, is becoming a “senior citizen,” according to Watkins and is reaching the end of its technological life. He says quality of their water research, which has included other spots around the globe, speaks to the need for another generation of the project.  Famiglietti says, though this data can’t replace ground measurements, he hopes it will be taken into account by state agencies faced with making the tough choices about California’s aquifers.