City of Visalia Water Conservation Plant Upgrade and Expansion – Visalia, CA
Client
- City of Visalia
Project Value 
$135 Million
Market
Water And Wastewater
Services
Design, Engineering
We served as the designer/engineer of record to upgrade and expand the WCP to 22 mgd with reliable biochemical oxygen demand, nitrogen removal, and tertiary treatment (Title 22) processes. Other important drivers include incorporating sustainability, pollution-free energy recovery, groundwater recharge, and extensive water recycling.
The scope of work involved a technology evaluation and life-cycle cost analysis to compare conventional tertiary treatment systems (i.e., tertiary filters and chlorine disinfection) with advanced systems (MBR and UV disinfection). The design team assisted the City with selecting and pre-purchasing a 22-mgd MBR. The MBR system produces high-quality recycled water for landscape irrigation, agricultural irrigation, and groundwater recharge. For disinfection of wastewater, UV light was the chosen technology. The design team also assisted the City with preselecting a renewable power generation system and related equipment. The IC engine system was sized to maximize the use of digester gas for power generation and heat recovery.
Additional scope included evaluating and preselecting turbo blowers and fine bubble diffusers for aeration, sludge disintegration for improving digester performance, and sludge dewatering equipment.
Other processes designed include fine screening structures and modifications to aeration basins, chemical feed systems, an anaerobic digester, an existing digester, digester gas storage and handling systems, and an odor control system. The biosolids-handling facilities include secondary sludge thickening, a food waste (grease) facility, anaerobic digesters, dewatering using screw press, and land application. Parsons assisted the City with applying and securing $500,000 in grant money from Southern California Edison to implement energy-saving ideas using California’s “Savings By Design” approach. Parsons also supported the city in preparing its SRF application and evaluating available grants for potential use on the project.
In an effort to develop sustainable and green energy alternatives, planning and preliminary design services were provided for a 1 MW solar photovoltaic system at the WCP, which was procured using the power purchase agreement (PPA) method.
Our Scope
- WWTP expansion design
- MBR design/integration
- UV disinfection systems
- Biosolids processing systems
- Energy recovery systems
- Startup & commissioning
