Reservoir 2B and 3B Replacement Project

Ardurra (formerly MKN) replaced an aging 0.1-million-gallon steel reservoir in South Laguna Beach with two new AWWA D100 welded steel tanks, eliminating significant seismic risk and restoring operational redundancy for South Coast Water District. The $6.3 million project was substantially completed in May 2025, delivered under the original $6.7 million estimate.

Key Highlights:

• Evaluated steel, concrete, and pre-stressed tank alternatives through mixing analysis and hydraulic modeling to optimize sizing and configuration

• Installed soil nail retaining walls up to 25 feet high on a steep, narrow site to accommodate both new tanks safely

• Designed tanks to current seismic standards, including hydrodynamic sloshing forces and full anchorage

• Consolidated two potential sites into one, reducing construction costs and minimizing disruption to the surrounding neighborhood

• Incorporated a bent-plate roof system and cathodic protection system to maximize durability and resist long-term corrosion

• Received two 2026 industry awards: ACEC-CA Engineering Excellence Commendation Award and CWEA SARBS Engineering Achievement Silver Award

Strategic site consolidation, seismically resilient design, and careful cost management delivered a durable, code-compliant facility under budget, ensuring reliable fire protection and water storage for South Laguna Beach residents for decades to come.