Some Pleasanton water customers may notice an earthy taste or odor in their drinking water over the next several days. This temporary condition is affecting multiple Tri-Valley water agencies and is associated with seasonal algae in the source water and planned State Water Project maintenance being conducted by Zone 7 Water Agency from June 27 through July 2.
The water remains safe to drink and continues to meet all state and federal drinking water standards. Zone 7 performs extensive water quality testing throughout the treatment process, and the City of Pleasanton is independently collecting samples throughout the distribution system to verify and confirm water quality.
Seasonal algae can produce naturally occurring compounds known as geosmin and methylisoborneol (MIB), which may affect the taste and odor characteristics of treated water, resulting in an earthy smell or taste. Temporary changes in water sources and treatment operations during the State Water Project maintenance period may make these conditions more noticeable. Zone 7 anticipates that changing water sources during the maintenance period will help alleviate the taste and odor issues.
Customers who notice an earthy taste or odor may find that refrigerating an open pitcher of water helps the taste and odor dissipate.
For additional information about seasonal taste and odor changes, including answers to frequently asked questions, please visit Zone 7 Water Agency’s Water Taste & Odor FAQ.
Public Works crews will continue monitoring water quality closely and coordinating with Zone 7 throughout the maintenance period. The City appreciates the community’s patience while Zone 7 completes its planned maintenance and treatment adjustments.