Conjunctive Use: Banking for a Dry Day
Traditionally treated as two separate resources, surface water and groundwater are increasingly linked in California as water leaders search for a way to close the gap between water demand and water supply. Although some water districts have coordinated use of surface water and groundwater for years, conjunctive use has become the catchphrase when it comes to developing additional water supply for the 21st century.
The Association of Ground Water Agencies (AGWA) released a conjunctive use report in late 2000 that identifies the potential to store 21.5 million acre-feet of water in groundwater basins from Kern to San Diego counties. The CALFED Bay-Delta Program’s preferred alternative includes a goal of implementing enough conjunctive use projects to create 500,000 to 1 million acre-feet of additional water storage. And in April, the Metropolitan Water District of Southern California (MWD) announced that it had awarded $45 million in state bond monies to nine regional conjunctive use programs that will yield approximately 64,000 acre-feet of water during dry years.
“We are going to put more and more water underground for that dry day when we need it,” said David K. Todd of Todd Engineers.
For example, this year’s dry weather conditions resulted in only a 35 percent supply for State Water Project contractors. The ability to tap a local source of groundwater – or a distant groundwater bank – during such periods can help a district cope with such drought-related cutbacks. Conjunctive use projects, in effect, allow water purveyors to meet the constant demand for water despite the state’s variable hydrology.
The idea of developing more underground storage has gained broad political support from all stakeholders – including environmental groups that appear to be opposed to any proposed new surface storage reservoirs such as Sites Reservoir.
“Conjunctive use will be a substantial part of the answer to water supply in the state,” said Greg Thomas, president of the Natural Heritage Institute (NHI).
And in this new era of collaboration, more and more regions are working to develop coordinated plans to share and manage groundwater and surface water resources. “Without regional cooperation, you cannot succeed,” said Ed Winkler, general manager of the Sacramento North Area Groundwater Management Authority, which is developing a regional conjunctive use plan. “Past solutions will not always fit the future and there is wisdom in diversifying your water supply.”
Each conjunctive use project, however, is different, with its own set of legal, political and technical challenges, and some question how much “new” water such projects will ultimately yield.
“There clearly is a growing interest in conjunctive management these days and in many cases, a strong belief that it is going to solve a significant portion of our water supply problems,” said hydrogeologist Anthony Saracino, a principal in the firm Saracino-Kirby-Snow. “I really don’t think that’s the case. It is a useful tool and can certainly help with increasing water supply reliability, but there are a lot of issues to overcome.”
Where do you get the surface water to store in a groundwater aquifer? How do you determine a groundwater basin’s safe yield? How long will it take to extract the groundwater? What about overlying landowners’ rights to the native groundwater? How do you protect the quality of that native underground supply? And in light of the current energy crisis, the costs to run groundwater pumps and recover the stored water joins the long list of issues that must be addressed as local districts, regional forums and state officials pursue plans to increase conjunctive use.
Some issues may prove more difficult to resolve than others. Perhaps the biggest challenge – although a somewhat intangible issue – is the question of trust. Trust in the technical information regarding an asset that is highly valued, but hidden. Trust in the idea that water artificially recharged into a groundwater basin will not contaminate the native water. Trust that the groundwater overlying g users have relied on for years will be there – even as others extract the new water.
“Trust will only come when the technical evaluation of a basin is made public and the public begins to understand how the basin works,” said Carl Hauge, chief hydrogeologist for the California Department of Water Resources (DWR). “People have had a hard time understanding conjunctive use, but until they understand it, they’re not going to support these export-import schemes.”
At the core of any conjunctive use project is a concept many in California have resisted -groundwater management. For a conjunctive use program to succeed, water must be measured and managed as it is extracted from and/or recharged into a groundwater aquifer. Yet managing a groundwater basin, to some, equals a state-dictated system for a resource that has, historically, been considered a property right of overlying landowners. And while the state’s surface water system is devoted to the concept of moving water from areas of plenty to areas of need, proposals to transfer groundwater from one area of the state to another invite suspicion.
“Trying to get past the political and institutional barriers is 80 percent of the challenge, to even get people to think that active conjunctive management is something they want to do,” said Mark Meeks, who is leading the conjunctive use component of DWR’s Integrated Storage Investigations.
Despite all of these stumbling blocks, there is growing interest in conjunctive use as providing at least one piece of the water supply puzzle.
“We live in a state extremely ripe for conjunctive use to succeed,” said Bill Mills, general manager of the Orange County Water District (OCWD), which has received national recognition for its progressive and ambitious groundwater recharge programs. “The big question,” he said, “is ‘can we resolve these issues in a timely manner?”
The constraints and opportunities for conjunctive use were the subject of an April conference, “Conjunctive Use: Successful Experiences and New Frontiers,” held in Ontario, Calif. The conference was sponsored by AGWA, a membership organization comprised primarily of southern California groundwater management agencies devoted to interagency solutions to groundwater management, the American Ground Water Trust and the Water Education Foundation.
This issue of Western Water focuses on conjunctive use. It includes background information explaining how conjunctive use works, discusses the potential storage capacity, provides an overview of the hurdles that must be overcome to develop a successful project, and profiles several projects. Much of the information was drawn from the April conference.
Additional information, including computerized graphics illustrating how conjunctive use works, can be found in the Foundation’s 11-minute video, Conjunctive Use: A Comprehensive Approach to Water Planning. More background information on California groundwater can be found in the Foundation’s Layperson’s Guide to Groundwater. Copies of the October 2000 AGWA report, Groundwater and Surface Water in Southern California, A Guide to Conjunctive Use, can be purchased from the Foundation.
NOTE: A complete copy of this 16-page magazine is available from the Foundation for $3. Visit our on-line store and add the July/August 2001 issue of Western Water to your shopping cart. Or, contact us by phone at 916-444-6240.
At one point in the Foundation’s new public television documentary, a special effect allows us to illustrate how Lake Tahoe is in danger of being transformed from the extraordinary, cobalt blue lake we see today into an average, everyday green lake. It’s a dramatic illustration of the scientific fact behind the well-known “Keep Tahoe Blue” campaign: algae is growing in Lake Tahoe at an alarming rate.
Our new program tells the story of how the many voices in the Tahoe Basin – once at-odds over who is at fault for the lake’s transformation – have united in a common effort to stop and reverse this trend. Narrated by Actor Bruce Dern, The Fate of the Jewel was produced by Sue Pearson Atkinson, the independent television producer who has been our partner on many programs.
Television is a powerful medium and through PBS documentaries such as this, we can teach millions of people throughout the West and the rest of the nation about our water problems, and potential solutions. The Fate of the Jewel will be released this fall on the PBS satellite. Watch your local channel for an air date. Video tape copies of the program as well as a Viewer’s Guide will soon be available, contact the Foundation for more information.
We have expanded our work in groundwater education in recent months. In partnership with the Association of Ground Water Agencies (AGWA) and Montgomery Watson, we developed a report on conjunctive use potential in southern California last year. In April, we helped AGWA and the American Ground Water Trust organize a conference on conjunctive use in Ontario, Calif. Chief Writer Sue McClurg drew upon that conference in developing this issue of Western Water.
In September, we will host our first Southern California Groundwater Tour (see details on our tour page and for April 2002, we will work with AGWA to develop and organize the program for their annual conference.
Also on the calendar for this fall is the Biennial Groundwater Conference co-sponsored by the Foundation, the University of California, Department of Water Resources and the Groundwater Resources Association of California. I am serving as co-chair of the planning committee for this important conference along with DWR’s Carl Hauge. The two-day conference will be held this fall in Sacramento.
But despite all this work, we still have not developed universal support to address a key groundwater issues of ongoing debate – whether groundwater is one word or two. When DWR switched to one word several years ago, we switched, too. Others, like AGWA, continue to favor ground water over groundwater.
However you spell it, it’s clear that groundwater is only going to increase in importance as we work to stretch supplies for all sectors of the water world.
In the News
California’s answer to the clean air vs. clean water controversy when the gasoline oxygenate MTBE was found in groundwater wells, lakes and reservoirs was to ban its use. Gov. Gray Davis issued this order in 1999, setting a target date of December 31, 2002, for the complete elimination of MTBE (methyl tertiary butyl ether) in California gasoline supplies.
State officials, in turn, petitioned the U.S. Environmental Protection Agency (EPA) for a waiver from the oxygenate requirement, arguing that California could meet clean air standards without an oxygenate. Oxygenates, designed to help fuel burn cleaner and reduce tailpipe emissions, are required under the federal Clean Air Act in certain smoggy regions, including much of California.
The Clinton administration never acted on California’s request and in mid-June, the Bush administration rejected it, saying the state had not demonstrated what the impact on smog would be from such a waiver. “We cannot grant a wavier for California since there is no clear evidence that a waiver will help California to reduce harmful levels of air pollution,” EPA Administrator Christie Whitman said in a prepared statement.
MTBE, classified by EPA as a possible human carcinogen, has been detected in approximately 10,000 water sources in California. Its turpentine-like odor and taste can be detected at levels far below health advisory levels developed by state and federal officials, forcing cities to close wells and find alternative sources of supply.
With the rejection of the waiver, the state will have to dramatically increase its use of ethanol – the other leading fuel oxygenate. Most of the nation’s ethanol currently is produced by the Midwest corn-belt states and California’s conversion to ethanol is viewed as a lucrative market for farmers in these states.
California officials fear the switch to ethanol will result in higher gas prices and potential gas shortages for the state’s residents. In a May 22 letter to Bush urging him to approve the waiver, Davis said that without it, Californians would have to pay at least $450 million more annually for their gas, predicting short-term increases of as much as 50 cents per gallon and long-term increases of 3 to 5 cents per gallon.
Ethanol industry leaders say the use of methanol will not drive gas prices up that drastically, and that they will be able to meet the anticipated demand.
California currently produces about 8 million gallons of ethanol a year. State Sen. Jim Costa, D-Fresno, calculates that 580 million gallons more will be needed once MTBE is phased out, and in mid-June he introduced legislation to provide $25 million in grants to California farmers to subsidize the production of ethanol from agricultural waste products such as rice straw.
On a separate front, U.S. Sen. Dianne Feinstein, D-Calif., has said she will introduce legislation that would allow oil refiners to produce reformulated gasoline without MTBE or ethanol as long as producers can meet clean air standards. Only Congress can change the oxygenate mandate.