
Reservoir Management System Replacement Phase IV
Owner
Moulton Niguel Water District
Location
Mission Viejo and Laguna Niguel, California
Value
$9.3 million
Completion
2026
Contractor
Pacific Hydrotech Corporation
Designer/Engineer
Brown and Caldwell
Project Overview
Butier Engineering, Inc. provided construction management and inspection services. Phase IV of the Reservoir Management System Program included the demolition of the existing OSG systems at four (4) RMS sites, including all equipment, connected piping, buildings, foundations, and utilities. The systems were replaced with 12.5% bulk hypochlorite or new OSG systems and ammonia systems. The scope of work included all equipment, new ammonia systems, connected piping, foundations, containment and separation of chemicals, block buildings, electrical, instrumentation, HVAC, shower/eyewash stations, and site modifications and improvements. New major equipment included bulk chemical tanks, metering pumps, reservoir mixers, instrumentation, and PLCs that interface with the District’s central SCADA system.
The reservoir sites included the following:
- El Dorado Reservoir (2.25 MG) – Located near 26491 Lope De Vega Drive, Mission Viejo, CA 92691. Work included new OSG systems and demolition of existing equipment, connected piping, buildings, foundations, and utilities.
- La Paz Reservoirs (Two 2 MG) – Located near 26842 Preciados Drive, Mission Viejo, CA 92691. Work included new OSG systems and the existing system was demolished at the start of construction to make room for the new RMS facility.
- Rancho Reservoirs (Two 1.5 MG and One 2.8 MG) – Located near the intersection of Golden Lantern and Hidden Hills Road, Laguna Niguel, CA 92677. Work included the construction of new 12.5% bulk sodium hypochlorite.
- Saddleback Reservoir (2.0 MG) – Located near the intersection of Marguerite Parkway and Medical Center Road, Mission Viejo, CA 92691. Work included the construction of a new 12.5% bulk sodium hypochlorite.
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