back to Treatment

White Slough Water Pollution Control Facility Multi-Year Treatment Facilities Design, Planning, and Regulatory Compliance Support

City of Lodi, CA

West Yost has been providing wastewater treatment and disposal system planning, regulatory compliance, and engineering design services for the City of Lodi’s White Slough Water Pollution Control Facility (WPCF) since the late 1990s. This project work started with a role in the development of a flexible Wastewater Master Plan to identify the improvements needed to address Lodi’s capacity and rehabilitation needs over a 25-year planning horizon. The Plan was completed in December 2000.

The Master Plan, followed by additional pilot studies, stakeholder negotiations, and regulatory coordination efforts provided by West Yost, guided Lodi through the completion of all the upgrades necessary for compliance. In 2005, Lodi constructed a cloth media tertiary filtration system and UV disinfection facilities. In 2009, Lodi constructed the facilities needed to expand the treatment capacity from 6.5 mgd to 8.5 mgd, while adding in the improvements needed to achieve reliable nitrification and denitrification.

In 2014 and onward, West Yost designed a new anaerobic digester, pumped-mixing system, flame arrester, heat exchanger, boiler, gas piping, and accessories as part of a project to increase the average flow capacity of the plant from 6.8 mgd to 8.5 mgd. Subsequently, plant staff discovered sludge in the attic space of two floating digester covers, and West Yost design replacement covers and the replacement of the gas-mixed systems with pump-mixed systems. In addition, West Yost designed a new digester gas/natural gas-fired boiler, heat exchanger and hot water piping loop, digester gas scrubbing and waste gas burner improvements, and new biosolids dewatering and storage facilities.

West Yost has also provided regulatory assistance services for Lodi over this entire period, including support with adoption of new NPDES Permits in 2007, 2015, and 2019.

Team Spotlight

Kathryn Gies, PE, ENV SP

Regulatory and Planning Practice Area Leader. Engineering Manager II

Charles Hardy, PE

Senior Engineer II

Bill Schilling, PE

Principal Engineer I