SCH Number 2019089002

Project Info

Title

ENV17-0002 (Emergency Recycled Water Storage Pond Project)

Description

The proposed project involves the construction and operation of an emergency recycled water storage pond, which would provide up to ten million gallons of additional emergency storage in the City's recycled water system. The approximately 5.9-acre, five-sided pond would have a varying width between approximately 225 and 308 feet, with a 21.8-foot height to the water surface and 14.4 inches of freeboard. The total project disturbance area is estimated to be 7.2 acres, including the pond site, access road, and temporary construction easement. The emergency storage would be utilized to reduce flows from the City's Hale Avenue Resource Recovery Facility (HARRF) during wet weather storm events. As part of the City's Eastern Recycled Water System Project (which is a separate but associated project under the City's larger recycled water project), the Hogback reservoir would be converted to recycled water. The second component of the Eastern Recycled Water System Project would be a new recycled water pipeline, to be extended from the converted Hogback Reservoir along the east and south sides of the proposed emergency storage pond (City File No. ENV16-0007) to provide recycled water to agricultural growers. The proposed project would tie into this new pipeline through a new fill pipe on the east side of the pond with a manual valve that would be opened during heavy storm events when additional storage is needed. The stored recycled water would be utilized for agricultural irrigation and would be emptied through a drain line on the southwestern side of the pond. The City has opted to construct additional emergency recycled water storage in their wastewater system, which includes the treated effluent from the City's wastewater treatment facility, the Hale Avenue Resource Recovery Facility (HARRF). This additional emergency storage is part of a requirement by the San Diego Regional Water Quality Control Board (RWQCB) that was established to reduce the amount of flow during wet weather storm events. The City has chosen to meet this effluent flow reduction requirement by constructing emergency recycled water storage in the eastern portion of the City's service area. Based on the latest Wastewater Master Plan prepared by Brown & Caldwell (2006), the City needs to provide ten million gallons of additional emergency storage to meet the Board's treated effluent storage requirement. The emergency storage would be utilized to reduce treated effluent flows from the HARRF to the land outfall only during wet weather storm events and only if the flows are exceeding the discharge capacity of the land outfall. Historically, when flows have exceeded the land outfall capacity, the treated effluent would spill to Escondido Creek. In years past, the RWQCB issued the City a temporary emergency live stream discharge permit which allowed the City to discharge tertiary treated recycled water to the creek. The RWQCB has indicated that the temporary permit would not be renewed in the future and has instead required the City to begin the process of developing additional emergency recycled water storage.

2 documents in project