White Slough WPCF Storage Expansion and Surface, Agricultural, and Groundwater Supply Improvement

White Slough WPCF Storage Expansion and Surface, Agricultural, and Groundwater Supply Improvement

The city of Lodi is proposing the construction of a 70-acre Expansion Pond and associated conveyance infrastructure at the City-owned White Slough WPCF. The Expansion Pond will consist of 4 individual ponds with an overall storage capacity of up to 388 acre-feet. The Expansion Pond will be used exclusively to store disinfected, tertiary-treated effluent produced by the WPCF for use as irrigation water on the 886.67 acres of agricultural land that surrounds the WPCF. The purpose of the project is to provide additional WPCF effluent supplies for agricultural irrigation on these properties and to offset groundwater pumping. The project would be funded by the DWR proposition 84 Grant Funding Program, which is intended to assist in the development of projects which increase agricultural and drinking water supplies, decrease groundwater pumping or assist in preserving water quality at source intakes. The City intends to divert filtered, disinfected recycled water tot eh new storage ponds. However, the diversion facilities that direct treated effluent to the existing storage ponds convey undisinfected secondary-treated water. Therefore, the Project needs to include new facilities that allow for diversion of tertiary flows separately from the existing effluent diversion facilities. Tertiary treated wastewater will be diverted from the effluent control chamber of the WPCF's existing Filter Pump Station structure and conveyed through a new 18-inch diameter pipeline. The Project will also include conveyance infrastructure to provide for delivery of the treated effluent from the new storage ponds to the City's existing irrigation water delivery system. During irrigation months (generally late April through Sept.) the new Tertiary Storage Pond Pump Station will pump stored water to the WPCF's existing main irrigation distribution box. From this location, the WPCF's existing irrigation distribution system can deliver this water to various City-owned agricultural fields. The White Slough WPCF requires expansion and additional measures to prevent excess surface water discharge tot eh Delta and decrease groundwater pumping for irrigation, rather than being discharged to the Delta. Overall, by combining the need to increase on-site wastewater storage with the need to reduce surface water discharge and groundwater pumping, the proposed project is anticipated to have a multitude of benefits that are both local and regional in scope. Some of the major benefits include increased irrigation water supply, improved surface water quality in the Delta, and the potential increase groundwater storage.

Lodi

San Joaquin