Planning Commission approves Carpinteria Advanced Purification Project after extended review and public comment

The Carpinteria Planning Commission on a 4-0 vote approved permits to build and operate the Carpinteria Advanced Purification (CAP) project, a water-reuse system that will treat wastewater to a potable standard and inject up to 1,200 acre-feet per year into the Carpinteria Valley Groundwater Basin for later extraction.

The project, presented to the commission by city planner Brett McNulty, would place the main treatment building and supporting equipment at the existing Carpinteria Sanitary District wastewater treatment plant, add roughly 5,475 feet of buried conveyance pipe and two injection well sites — one in the Meadowview Lane right-of-way and one at Linden Avenue near St. Joseph’s Church — plus monitoring well clusters. The Carpinteria Valley Water District will operate conveyance and injection systems; the Sanitary District is leasing site space at the treatment plant for the advanced treatment facility.

Why it matters: the CAP project is intended to reduce Carpinteria’s reliance on imported supplies and to help stabilize groundwater levels in the coastal basin, reducing susceptibility to seawater intrusion. The project team told commissioners the facility is designed to produce up to 1,200 acre-feet per year (about 1.2 million gallons per day) and could supply roughly one-quarter of the district’s water needs.

Project details and operation Brett McNulty told the commission the AWPF footprint is on a 2.78-acre parcel adjacent to Carpinteria Creek and the existing wastewater plant and includes a main building, a 200,000-gallon equalization tank (clear well), piping and electrical improvements and floodwall extension. Treated water would travel via buried PVC pipelines along Olive and Maple avenues and cross under Highway 101 to Meadowview Lane, where two injection wells and monitoring clusters will be installed. The district will also install a 24-inch buried pipe to store backwash water so the project does not rely on an aboveground backwash tank.

The Carpinteria Sanitary District’s general manager, Craig Murray, described the work as part of climate-adaptation and flood-protection planning: “This is an important project for us,” he said, noting the main electrical feed to the plant sits outside the floodwall and the project would allow vulnerable infrastructure to be enclosed and protected.

Public comments and…