Getting Serious About Salt
Urban Water Purveyors Seek Solution to Mounting Problem
Sodium, chloride, magnesium, calcium, potassium, sulfate, carbonate, bicarbonate and nitrate can all be summed up in one word: salt. We can taste it on our skin when we sweat and we add a common variety of it (NaCl – sodium chloride) to our meals to offset blandness. Salts are naturally occurring minerals and are integral to life on this planet.
But just as salts are necessary for survival, too much of them can kill. An overabundance of salts can even leave oceans lifeless as exemplified by the Dead Sea in the Middle East.
In a semi-arid climate such as California’s, monitoring and maintaining water supplies is essential and as a result, how to handle salt is an especially important – and complex – issue. The effects of increased salinity permeate nearly every facet of water in California. As the leading agricultural state in the nation, farmers must have quality water to grow their crops. Salt can, and has, ruined millions of dollars worth of produce. This is complicated by the fact that the very nature of irrigation can add salt to water supplies by flushing salts from the soil and into water sources.
The September/October 1995 Western Water dealt specifically with salts in agriculture and this issue contains a short update of developments in Westlands Water District. But as the nation’s most populous state, California’s urban areas also suffer great financial hardship from saline water and for that reason, this issue of Western Water intentionally examines salt in the urban setting.
According to U.S. Bureau of Reclamation (Bureau) figures, the Lower Colorado River Basin suffers an estimated $750 million a year in economic damage as a result of saline Colorado River water. Approximately $382.5 million of that damage occurs to residential areas, $180 million to infrastructure utilities and $37.5 million to industry. Southern California is the largest user of this water supply – about 5.2 million acre-feet annually in recent years.
The impacts of salt on urban areas, however, don’t stop with tangible damage to pipes, appliances and water heater corrosion. Health concerns also have been raised about the carcinogenicity of disinfection byproducts created when water high in organic matter and certain ions (including bromide – found in sea water) is treated with chlorine and other disinfectants.
Groundwater and water recycling also are susceptible to salt in the water supply.
“In this era of competition over water supplies, salt is now a serious factor in how far we can stretch that supply, especially with regards to water recycling and conjunctive use,” said Byron Buck, executive director of California Urban Water Agencies (CUWA).
Water recycling and groundwater recharge depend on water low in salts to be effective and both water management techniques have been identified as increasingly important sources of water for California into the future. With conjunctive use – the practice where water is stored underground for use in dry years – becoming more prevalent as a water management tool for urban areas, contaminated groundwater basins can pose a serious problem. Likewise, areas dependent on recycled water can see the recycling process severely limited by increased salt in the source water supply. Ironically, the salt content of imported water increases just when recycled water and groundwater pumping are needed the most: during a drought.
For these reasons, improving the quality of California’s urban water supply by reducing salt is fast becoming an important goal of water purveyors around the state. These concerns were highlighted at a January 1999 Salinity Summit held in Pomona. There, 100 senior managers and technical experts representing 60 agencies met to discuss a regional management plan to address salts. In an April 14 letter signed by sponsors of the summit, salt was called “one of the state’s biggest water quality problems going into the twenty-first century.”
“Salinity in the Central Valley and southern California is probably the biggest water problem in the state that isn’t being adequately addressed,” said Walt Pettit, executive director of the State Water Resources Control Board (State Board), the agency responsible for setting and enforcing state water quality standards.
One method of reducing salts in urban water supplies is by controlling and improving the source of the water used by California cities. California, with one of the most intricate water systems in the world, depends heavily on an imported water supply. The bulk of the state’s population – over 20 million - live in southern cities. Much of this population is dependent on flows from the Colorado River, a water source with (on average) over twice the salts of northern California water sources. Water purveyors in southern California, such as Metropolitan Water District of Southern California (MWD), blend salt-laden Colorado River water with typically less salty State Water Project (SWP) water from the Sacramento-San Joaquin Delta (Delta) to reduce the overall salt content in their supply.
“There seems to be an inseparable relationship between quantity and quality of water supplies,” said Andy Sienkiewich manager of the local resources program for MWD, the state’s largest water wholesaler with 16 million customers. “One of the classic dilemmas we see is that during a drought, salt content increases in imported State Water Project water and that leads to a greater use of that imported water for blending. Recycled water also becomes saltier and less attractive to irrigators at a time it is needed the most.”
Conversely, Sienkiewich said, the less saline the imported water sources, the less SWP water is needed for dilution of Colorado River supplies. In the past, seasonal demand controlled the amount of blend and MWD customers sometimes would receive straight Colorado River water with a salt content of up to 700 mg/L during the winter months. MWD is now working to operate its system to provide its customers with a better quality 500 mg/L blend on a year-round basis, consistent with the secondary standard for TDS.
Water from the SWP originates in northern California’s Feather River. Flows from the Feather combine with those of the Sacramento River and other rivers on the way to the Delta. There, DWR exports that water via the California Aqueduct to the Bay Area and central and southern California. But once it enters the Delta, this fresh water is subject to hydrologic conditions (such as tides, winter runoff volume, saltier San Joaquin River flows, agricultural return flows and urban discharges) that can drastically increase salts in the SWP, especially during drought years.
CALFED, the state-federal program involving regional stakeholders developing a “fix” for the Delta’s ailments, is working on solutions to improve water quality for the region and, consequently, for southern California.
“The key issue when dealing with salt loads is to ensure the ability to use and reuse water,” said Steve Ritchie, deputy director for CALFED. “It starts by focusing on source control for salts in the San Joaquin River Basin in terms of better drainage management and agricultural efficiency.”
Although a new two parts per thousand salinity standard for the Delta was adopted by the State Board in 1995, which water users ultimately must give up how much water to meet those standards is still being debated.
Water supply is not the only factor affecting salt loads in California’s water. The use of salt in water softeners has fostered serious disagreements both within and outside of the water softening industry. This debate is continuing in the state Legislature over the ability of regions to regulate these devices that contribute significantly to increased total salt in urban wastewater and ultimately, urban recycled water and groundwater supplies.
This issue of Western Water examines the problem of salt in urban water supplies and what can be done to lessen the continual buildup of such salts.
by Josh Newcom
NOTE: A complete copy of this 20-page magazine is available from the Foundation for $3. Visit our Products Page and add the September/October 1999 issue of Western Water to your shopping cart.
For me, fall is synonymous with “Back to School,” a season of learning new facts and discovering new ideas. At the Foundation, we strive to educate all ages about water and have a wide variety of programs available for children and adults. As students everywhere prepare to hit the books, I thought this would be a good opportunity to review our classroom curricula.
Under the able leadership of Education Director Judy Wheatley, the Foundation has developed lesson plans for grades 4 through 14. These programs are all consistent with the standards of the California State Frameworks for Science and History/Social Science. For fourth through sixth graders, there is The California Water Story in which students learn about the state’s geography and history.
Students in grades 7-10 can learn about California’s vast groundwater resources in our Groundwater Education program, a 52-page teacher’s booklet with lesson plans, lectures and laboratory exercises. Two lessons are available in Spanish. Project Water Science is a general science unit designed for physical or earth science classrooms in grades 7-12 and includes lessons on nonpoint source pollution. California Water Problems offers students in grades 9-14 the chance to take on the role of the various interests and parties involved in four critical water challenges, including how to solve the Delta dilemma.
In addition to these programs, Judy serves as the California coordinator of Project WET – Water Education for Teachers. This nationwide program has developed a broad curriculum with more than 90 lessons designed for grades K-12. The 530-page guide is available (for a nominal fee) to classroom teachers, park rangers, naturalists and scout leaders who participate in a Project WET workshop. Contact the Foundation for a calendar of upcoming workshops.
A new docudrama and lesson plan booklet, Fountains of Columbia, comes just in time to recognize the California Sesquicentennial, the 150th anniversary of the Gold Rush. The video tells the story of a young girl growing up during the 1850s in the mining town of Columbia. The innovative film, part of the California Legacy 2000 series, was developed by Cambria Productions in association with the Foundation and the Metropolitan Water District of Southern California. A teacher’s lesson plan accompanies the video; the package will be available soon.
For young adults who want to take leadership roles on California water issues we offer our Water Leaders Program. Applications for our fourth annual class are due Nov. 30. Please see page 14 for more information and call for your brochure.
Finally, we encourage every adult involved in water issues to join us on one – or all – of our annual water tours. The last tour for 1999, the Northern California Tour, is Oct. 6-8. We are now working on the 2000 tours – including a new one that will examine the watersheds of the American River, Lake Tahoe, Truckee River and Yuba River. Watch the web for more details or call and request to be put on the mailing list for our upcoming tour brochure.
In the News
Re-watering the San Joaquin
A project currently sending water down a dry, 19-mile stretch of the San Joaquin River could be a sign that members of a long-standing feud over water rights are laying down their swords – at least for the time being.
Under a pilot program agreement between the Friant Water Users Authority (FWUA), CALFED, the U.S. Bureau of Reclamation (Bureau) and the Natural Resources Defense Council (NRDC) (and 14 other environmental groups), 35,000 acre-feet of water are being released from Millerton Reservoir to the tune of $2.5 million dollars in funding from CALFED.
In its natural state, water from the San Joaquin River flowed unimpeded from the mountains to the Sacramento-San Joaquin Delta. With completion of Friant Dam in 1944, water from the reservoir is transported through the Friant-Kern and Madera canals to Eastside farms. Only a small amount of water is released for riparian water-right holders below the dam. As a result, the stretch of river above Mendota Pool seldom sees water.
In 1988, 15 environmental groups headed by NRDC sued FWUA and the Bureau under Section 5937 of the State Fish & Game Code. The suit claims that the lack of water in the river channel has caused serious detriment to the riparian ecosystem and specifically, fish populations in the San Joaquin.
David Behar, a consultant with NRDC and legal representative for the plaintiffs, says the pilot project flows provide three objectives: restoring riparian vegetation along the stretch of the river through seed germination; keeping the cottonwood and willow seedlings established during recent flood years growing; and producing data on the impacts of the releases to area groundwater and surface water losses during the flows.
At the onset, flows from Friant were being released at about 600 cfs and by the end of the program will be cut in half. The ramping down of the flows, according to Behar, is intended to mimic the natural hydrograph of the river.
For FWUA, the project provides a chance to aid in river restoration without an impact to water supply. According to Dan Fults, special projects officer for FWUA, the water users will suffer no net loss on the 35,000 acre-feet of water being released over the four-month period from July to the end of September/early October. Fults said monies are in place to purchase any missing water.
“The $2.5 million being fronted by CALFED will allow us to purchase the water lost because of ground [water] percolation and evaporation,” Fults said. Costs include pumping and conveyance charges for the purchased water.
The remaining 20,000 acre-feet eventually reaches the Mendota Pool where it is consumed by federal contractors on the westside – users who normally get their water from the Delta via the Delta-Mendota Canal. Water normally consumed by the westside contractors is then redirected to the California Aqueduct and the Cross Valley Canal where it is returned to FWUA participants in the pilot project.
So why would the parties involved in the project be interested?
“Rather than proceed in court, we believed we would be better off seeing what we could do in a cooperative effort,” Fults said.
Behar agreed. “It’s a step toward resolution of the issues that have haunted this river,” he said. “It’s also a resolution of the lawsuit to the extent that it demonstrates an ability to make progress.”
But Behar also expressed the coalition’s desire to continue restoration efforts in court, if need be. “It’s about rehabilitating a river back to something that resembles a natural river,” he said. “You don’t just add water and stir.”
Whether or not the project will continue into the future remains to be seen.