Risk of Lead Extremely Low
in Local Drinking Water
The recent news about lead-contaminated drinking water in Flint, Michigan, has raised a lot of questions about whether it can happen elsewhere in the country.
Locally, in Zone 7 Water Agency's service area, lead levels are controlled and monitored closely, both by Zone 7 and the water retailers that deliver your water. The Flint crisis is extremely unlikely to occur here, for the following reasons:
- Lead in drinking water rarely comes from a water treatment plant or from water mains of the type and age used in this area. Primary local sources of lead are older faucets, plumbing fixtures and lead solder within the home and from lead service lines, if any are present.
- Lead can be leached from such sources in the presence of corrosive water. However Zone 7 adjusts pH as a corrosion-prevention treatment which is approved by the State’s Division of Drinking Water.
- The City of Flint had changed its water source, which altered the water’s pH balance making the water extremely corrosive. Because of the city’s bankruptcy, the city did not have the money to implement appropriate corrosion-control measures to prevent lead from leaching from old pipes that were present throughout the area into the tap water.
- Zone ‘s corrosion-control program has been working effectively for decades. There has been no significant change in supply since its implementation.
- Recent rate increases have assured that Zone 7 has the money to continue all appropriate treatment needed to maintain high-quality drinking water.
- Zone 7 groundwater supplies that are not treated with reverse osmosis do not require any pH adjustment for corrosion control because adequate protection is provided by the naturally high minerals, alkalinity and calcium content of the groundwater.
- Zone 7 does more than simply comply with regulations; we set internal goals that go above and beyond the letter of the law. Our water treatment plants continuously monitor the pH of water as well as other important parameters 24 hours a day, seven days a week.
- Zone 7’s state-of-the art Environmental Laboratory Accreditation Program-certified laboratory performs lead testing throughout the year to ensure our delivered water is in compliance with the law.
- Under the Lead and Copper Rule, local water providers are required to monitor and report the effectiveness of corrosion control programs in their distribution systems by analyzing samples taken from customers’ water taps. They also are required to provide their customers with an annual Consumer Confidence Report (CCR) - a water quality report that details water quality testing results for the prior year.
- Your local water retailer (the City of Livermore, the City of Pleasanton, California Water Service Company in Livermore, or Dublin San Ramon Services District) reports water quality sampling results in its CCR.
Despite the fact that California requires new household plumbing and fixtures to be lead-free, lead is still present in some older plumbing fixtures, especially those originally installed in houses built before 1986. The addition of corrosion-control chemicals helps to prevent any lead that might be present from leaching into your tap water. Results of required lead testing is reported in the annual Consumer Confidence Reports from Zone 7 (see http://www.zone7water.com/index.php/publications-reports/reports-planning-documents/36-public/content/120-consumer-confidence-report
) and your water retailer.
Helpful resources on lead:
For more information from Zone 7 Water Agency
, you can contact Water Quality Manager Gurpal Deol at:
Assessing the Adequacy
of Local Water Supplies to Meet
Future Needs of the Community
Zone 7 Water Agency’s newly released Water Supply Evaluation Update concludes that while new alternative supplies can help shore up the Agency’s long-term potable water reliability for its urban customers, the community will always depend on Delta conveyance to import the vast majority of its water.
About 80 percent of the water delivered by Zone 7 to Livermore, Pleasanton, Dublin and the Dougherty Valley in San Ramon is Sierra snowmelt captured by the State Water Project in Lake Oroville and conveyed through aging, vulnerable, non-ecofriendly facilities in the Delta. That makes a Delta solution critical to restoring long-term water reliability for the Tri-Valley community, even as Zone 7 continues to work aggressively on other fronts to develop locally controlled water supplies such as optimizing recycled water use and maximizing conservation.
The update to Zone 7’s 2011 Water Supply Evaluation provides background for Zone 7’s 2015 Urban Water Management Plan. This Plan must be updated and submitted to the state every five years. The Plan is required to address water availability for urban uses. In preparation, the updated Water Supply Evaluation or WSE takes a conservative approach, assuming maximum reasonable demands during the study period and includes lessons learned from the current drought. The WSE conservatively assumes that Tri-Valley customers will resume using 80 percent of the water they used before drought restrictions were put in place in the first study year and then evaluates both projected development and a more rapid development, again to assure that adequate supplies will be available for all reasonably foreseeable scenarios.
Measures identified to potentially diversify drinking water sources for increased future reliability include 1) desalination of brackish Delta Water in a consortium with Contra Costa Water District and other Bay Area water suppliers, and 2) expanded water recycling using highly purified waste water. A recent public poll showed growing support for use of purified recycled water treated through reverse-osmosis technology, especially if the water is not used directly.
The WSE concludes that desalination and enhanced use of recycled water could improve reliability especially during droughts, but that neither one can solve Zone 7’s long-term challenges without the California WaterFix, which addresses the Delta's broken water conveyance infrastructure. The California WaterFix is identified as being the least costly per acre-foot of water developed of the measures evaluated.
To view a copy of Zone 7's Water Supply Evaluation Update, click here
Updated California Water Action Plan
In January, the California Natural Resources Agency, the California Department of Food and Agriculture and the California Environmental Protection Agency released the 2016 Update to the California Water Action Plan: http://resources.ca.gov/california_water_action_plan/
. The 2016 Update includes both the California WaterFix, planned to restore the reliability of the Valley’s primary source of water by upgrading the conveyance infrastructure through the Delta; and California EcoRestore, planned to improve the Delta’s troubled ecosystem.
Two years ago, the Zone 7 Board adopted a resolution supporting the original California Water Action Plan which also included support for the co-equal goals for the Delta of water reliability and ecosystem improvements. Last month, the state updated the California Water Action Plan, acknowledging progress made over the last two years and shifts in approach including the new California WaterFix and California EcoRestore. A brief overview was provided to the Zone 7 board at the February 17, 2016 Board meeting (video to be posted at http://www.zone7water.com/index.php/36-public/content/210-2016-board-meetings
). Further discussions are scheduled for the March 16, 2016 Zone 7 Board meeting.
California WaterFix maintains the co-equal goals of increasing statewide water supply reliability and, in coordination with California EcoRestore, enhancing the ecologically fragile Delta. It would modernize the nearly 60-year-old State Water Project conveyance infrastructure that takes water released from the Oroville Reservoir through the Delta by replacing the most vulnerable section of the conveyance infrastructure with two 30-mile long tunnels linking the Sacramento River to existing pump facilities in the south Delta.
The existing State Water Project (SWP) infrastructure is outdated, seismically vulnerable, inefficient and in desperate need of repair and upgrades. The California WaterFix will improve reliability by:
- reducing the vulnerability of the SWP to earthquakes, climate change, sea level rise and outages due to maintenance and environmental impacts,
- not only preserving the reliability of existing supplies but restoring supplies lost due to regulatory rulings that limit pumping due to potential impacts on endangered species of fish in the Delta, and
- improving the water quality of SWP deliveries, reducing the salt loading on the local groundwater basin and reducing salt content for untreated water users.
While other Delta proposals have been put forward, the California WaterFix is the only one that has taken over ten years to develop, undergoing an unprecedented level of public engagement with more than 600 public meetings conducted and allowing more than 300 days of public comment on related environmental documents. The project has been developed based on the best science available; for example, the intakes have been sited so that they avoid the highest densities of sensitive fish species and are designed with state-of-the-art screening facilities.