East Bay Municipal Utility District has begun the Carter and Arroyo Reservoir Improvement Project with the intention of enhancing water quality, renewing aging infrastructure, and improving operational flexibility and resiliency for the Carter Pressure Zone located at the end of Alta Mesa Drive in Moraga. The project also includes replacing the Town’s existing Arroyo Reservoir with two new tanks located at the end of Shannon Court.

    EBMUD held a community Zoom meeting on Jan. 29 to discuss their plans and answer any questions from the public. The utility’s representatives included: EBMUD Board Director Marguerite Young, Community Affairs Representative Joe Voelker, Associate Civil Engineer Construction Division Michael Reid, Manager of Water Distribution Planning Dave Rehnstrom, Manager of Construction Division Michael Hartlaub, Director of Operations and Maintenance Dave Briggs, and Senior Civil Engineer Ben Townley.

    Besides the aforementioned objectives, additional goals include maintaining fire flow capacity for emergency response readiness and improving site safety by incorporating the latest safety standards at Carter Reservoir.

    Until recently, Arroyo Reservoir was the only facility in service. It holds 1 million gallons of water. The Carter Reservoir had been out of service since 2011 and was not contributing to the system.  Both pumping plants worked together to move water to its destinations with a total pumping capacity of 1.1 million gallons per day. With that combined capacity, only Arroyo Reservoir has been the sole operational storage facility for the past 14 years.  Even though Carter Reservoir had been out of service for over a decade, its water distribution system was still operational to maintain existing fire flow requirements to protect the Town.

    Phase 1 of the Project took place between April and December 2025 with the rehabilitation of Carter Reservoir and its return to service with a new protective coating and roof replacement to ensure long-term reliability. During this time Arroyo Reservoir remained functional.

    January 2026 to December 2027 will see the replacement of Arroyo Reservoir which will entail substituting it with two smaller tanks, each with a 0.29-million-gallon capacity, for a total of 0.58 million gallons. The replacement will serve to modernize the water distribution system and improve flexibility during seasonal demands.

    The entire project is expected to be completed by December 2027 with a total water storage capacity of 0.83 million gallons that will balance supply and demand.  The pumping capacity will remain at 1.1 million gallons, thereby ensuring continued water reliability and fire protection for Moraga.

    EBMUD wants to reassure residents that no “hot work” will be done during Red Flag Warning days. This means that no electrical work will be performed that might cause sparking to dry grasses. There will be a dedicated fire watch during all hot work, and any areas around hot work will be wetted before and during construction.

    Additionally, water service will continue throughout the construction process with reliable pressure during the Project. EBMUD addressed Moraga-Orinda Fire District concerns by adding an on-site generator.

    Sign up for alerts at:  ebmud.com/alerts. For any questions send emails to: construction-east@ebmud.com.