El Sobrante, California

To enhance water quality and service resilience for East Bay Municipal Utility District (EBMUD) customers, the Sobrante Water Treatment Plant (SOWTP) is undergoing phased upgrades that expand capacity and improve treatment reliability. These upgrades are designed to increase the plant's capacity from 60 to 80 million gallons per day, accommodate drought contingency operations using water from the Folsom South Canal Connection, and reduce disinfection byproducts.

The improvements, executed in two phases, include new treatment facilities such as flocculation and sedimentation basins, gravity thickeners, a chlorine contact basin, and dual-media filters. Supporting infrastructure enhancements include a new maintenance building, upgraded site access and security features, and site-wide landscaping and stormwater management improvements.

Merrill Morris Partners provided landscape architectural services in support of the environmental review, site planning, and design documentation. MMP's contributions include:

• Visual and site context analysis to guide aesthetics and screening strategies.
• Concept development and detailing of landscape and site design for all above-grade facilities.
• Photo-realistic visual simulations illustrating site evolution through multiple phases of construction and vegetation maturity.
• Development of the Aesthetics Design Report, including site plans, planting schemes, finishes, and visual simulations for use in the Environmental Impact Report.
• Participation in community and agency presentations, refining designs in response to stakeholder feedback.
• Coordination with the consultant team to ensure visual quality aligns with site functionality, security, and long-term maintenance needs.

MMP’s work supports both CEQA compliance and long-term integration of the SOWTP within its surrounding landscape and community.

Owner/Client: EBMUD

Team Lead: MWA Architects