Water quality

EBMUD Water Operations Update 

EBMUD makes adjustments to the way we operate our vast system for reasons including infrastructure improvements, seasonal changes, drought response, and shifting water demands from customers. In all cases, the water that reaches customer taps meets or exceeds all standards for safe drinking water.

Most of EBMUD’s water supply comes from Pardee Reservoir about 90 miles east of our service area. Because of the drought, however, we are relying more heavily on local reservoirs compared to a typical year. This locally stored water has more minerals, making it taste more salty. In addition. the water from east bay reservoirs can be affected by algae blooms which give the water an earthy or musty taste and odor. Both the Sobrante and Upper San Leandro Water Treatment Plants treat water from these local reservoirs. Their ozonation systems are designed to remove these smelly compounds but not the minerals. Regardless of the treatment plant in service, all customers receive high-quality drinking water.

Lower water levels visible at USL Reservoir: Hikers along Upper San Leandro Reservoir may notice lower supply levels as EBMUD uses this local reservoir to supply more water than usual to accommodate various construction projects in our water system. In addition, EBMUD is also managing our water supply during the drought. Our intent is to refill USL later in the fall.

For more information about water quality or to report a water quality concern, call EBMUD at 1-866-403-2683. 

snowmelt.jpgEBMUD is committed to providing high-quality drinking water for all of our 1.4 million customers. Our drinking water consistently meets or surpasses state and federal drinking water standards.

When precipitation is plentiful, ninety percent of EBMUD’s water comes from the Mokelumne River watershed. This 577-square mile area feeds EBMUD’s Pardee Reservoir on the western slope of the Sierra Nevada. In dry years, EBMUD expands our reliance on other supplies such as Sacramento River water from the Freeport Regional Water Project. No matter the source, you can rest assured that EBMUD is committed to quality.

Before water reaches your tap, EBMUD takes many steps to ensure its quality. This starts with carefully managing and protecting our watershed lands and reservoirs. EBMUD then treats the water and maintains its high quality through a complex system of pipes, pumps, and reservoirs.

Every day of the year, EBMUD's laboratory tests water samples to ensure that water quality meets federal and state standards, checking for trace organics like pesticides, metals, and microbes. These efforts ensure that all customers receive high-quality drinking water.

Annual water quality report 

AWQR thumbnail.jpgEBMUD is pleased to report that in 2020 your drinking water quality surpassed every state and federal requirements that safeguard public health. If you would like a report mailed to you, please email us or call 510-986-7555.

Previous years' reports can be viewed on the Archives page.

Water quality FAQs

Customers may have similar water quality concerns. Find answers to the most common water quality questions in our Frequently Asked Questions page.

If you still have questions, concerns or problems regarding water quality, such as taste, odor, appearance, etc., or if you have a water quality emergency, please contact us at 1-866-403-2683.

Water treatment

Every drop of water that comes out of your tap is first treated at one of our treatment plants at one of our treatment plants. EBMUD's six water treatment plants in the East Bay can filter and process more than 375 million gallons of water daily.

Take a virtual tour of Orinda Water Treatment Plant.

Water sampling and testing

In laboratories and in the field, EBMUD samples and tests your water extensively to make sure it is safe to drink. We look for more than 100 substances in the water including microorganisms, pesticides, herbicides, asbestos, lead, copper, petroleum products and by-products of industrial and water treatment processes. More than 20,000 annual laboratory tests ensure the safety of your drinking water.

Public Health Goals Report

Every three years, the District is required to prepare a report with information about any contaminants detected above the state's Public Health Goals (PHGs). PHGs are non-enforceable standards set at very low levels that pose no significant health risk. We are also required to hold a public hearing at which the report is discussed, and receive public comment. For the 2016-2018 calendar years, the report can be found below. The report was discussed at the July 9, 2019 Board of Directors public meeting.  

Document Type Size
Public Health Goals Report (2016-2018) PDF <1 MB