River Islands Lake Management

Lathrop, CA

PACE provided engineering services to manage a system of 26 interconnected lakes located in the River Islands development in Lathrop, California. The 5,000-acre community is located along the San Joaquin River and provides residents access to riverfront trails, parks and green spaces, schools, and business centers. The lakes are spread throughout the development, providing over 5 miles of shoreline access and waterside recreation for the community to enjoy. The lake system is multifunctional, providing stormwater capture and detention, water quality management, and irrigation for the development. Equalization piping connects all 26 lakes and optimizes the system’s detention capacity. The lake system is designed to capture and detain the 100-year, 48-hour storm. Stormwater runoff is directed to the stormwater evacuation pumps, which route and discharge excess stormwater to outfalls located along the existing Paradise Cut. Water quality is maintained by recirculation, alum and ozone treatment, aeration, sediment basins, and a wetland system. Two large pump stations, with respective capacities of 54 cfs and 75 cfs, house all of the stormwater evacuation pumps, recirculation pumps, and irrigation pumps, allowing for efficient, centralized management of the entire lake system.

Key Features:

• Stormwater capture and detention for a 5,000-acre community
• Irrigation pumping providing consistent, non-potable water supply
• Flood control utilizing a stormwater evacuation pumping system
• Equalization and circulation piping connecting 26 lakes
• Lake water quality control system with alum and ozone injection, aeration system, wetlands, and sediment basins
• 2 centralized pump stations with respective capacities of 54 cfs and 75 cfs