Westlake Reservoir - 2008 ASCE Project of the Year Award, Santa Barbara and Ventura Counties:

• Owner: Calleguas Municipal Water District
• Cost: $13,500,000

The existing Calleguas Municipal Water District 7.0 MG concrete reservoir, located in the City of Thousand Oaks, had been severely damaged during the Northridge earthquake and was no longer considered adequate as determined by Perliter & Ingalsbe.

The District's staff determined to demolish the existing partially buried 20' high rectangular reservoir and construct a new 5.0 MG concrete reservoir at a higher elevation to meet current hydraulic requirements. Perliter & Ingalsbe provided a full range of engineering services including assessment of the existing reservoir, preliminary layout of the new facilities, final design of the reservoir and associated components, and bidding and construction support services.

Major Components and Special Features:

• Demolition of existing 7.0 MG concrete reservoir
• 260'x 160'x 20' deep buried cast-in-place concrete reservoir unit with total storage capacity of 5.0 MG
• Reservoir access road and facility perimeter road
• 30" inlet and outlet pipes and valves
• 24" reservoir overflow, 12" drain, 6" sub-drain, and washdown piping
• Three large concrete vaults
• Hatches, ladders, stairways, gravity vents, etc.
• Electrical power supply, controls and instrumentation

• Entrance gate and retaining walls
• Security features, including intrusion alarms, security fencing, etc.
• Landscaping and irrigation system
• Raising reservoir pad by 15 feet using soil cement
• Proximity to affluent residential area and public outreach program
• Narrow access road
• Practically no staging and storage space
• Aesthetic requirements of the City and community HOA