(Credit: Pixabay)California’s West County Wastewater (WCW) will undergo a comprehensive energy, infrastructure, and process improvement project designed to significantly reduce the organization's carbon footprint and greenhouse gas emissions. This infrastructure upgrade project will reduce WCW’s overall greenhouse gas emissions by 93% at its Water Quality and Resource Recovery Plant and is expected to save more than $83 million over the project's lifetime.
The new comprehensive infrastructure project will help WCW achieve its vision. Led by ENGIE North America, the initiative will include significant upgrades to WCW's Water Quality and Resource Recovery Plant. Two new digesters, an addition of 1.1 megawatts (MW) of solar power generation, a thermal sludge drying system, and solids dewatering, among other improvements, will greatly improve WCW's control over its handling of biosolids.
Historically, biosolids produced by WCW have been sent to landfill due to the fact they did not meet the high-quality standards required for beneficial reuse. By generating Class A biosolids—suitable for agricultural and other reclamation uses—these upgrades will eliminate organic material being sent to landfill. This will prepare the organization for the 2022 implementation of SB 1383, the "Short-Lived Climate Pollutants: Organic Waste Reductions" regulations and reduce ongoing disposal costs. The project will also result in a substantial reduction in greenhouse gas emissions from the decomposition of sludge in the landfills.
ENGIE will implement the plant improvements and maintain the installed equipment over the next 20 years under an energy savings performance contract. ENGIE is targeting a 4.2 million kWh reduction in WCW's annual energy use.
The scope of the project comprises a 1.1 MW solar power system, LED lighting, electric vehicle charging stations and wastewater treatment plant upgrades including a new grit separation system, rotary drum thickeners, a high efficiency aeration blower, new digesters, a 450 kW cogeneration system powered by biogas from the digester, a sludge dewatering system, a sludge thermal dryer system and equalization basins. Together, these systems' onsite generation will meet close to 100% of the district’s facilities and wastewater treatment electricity needs.
