East County AWP construction boosts cost, but officials say recycled water supply is worth the price

By Mike Allen

Photo: Education Center at AWP plant

December 5, 2025 (Santee) -- Three years into construction, the massive East County Advanced Water Purification Program is approaching the finish line late next year when the region’s sewage now being treated at Point Loma will be pumped to a new Santee plant and converted to drinkable, purified water.

Last month, the four-person board that oversees the more than $1 billion AWP project approved a $34 million allocation for another phase of Package 5 of the project that broke ground in mid-2022. There are five packages for the AWP that is a collaboration among four agencies—Padre Dam Municipal Water District, San Diego County, the city of El Cajon, and Helix Water District.

While the main sewage treatment and water purification plant is out of sight at the farthest end of Fanita Parkway in Santee, there’s plenty of pipeline work that’s evident to anyone driving in and around Santee and other parts of East County.

Pipelines that will carry sewage from East County to Santee, and those carrying purified water to La Mesa via Lakeside, are conspicuous along Mission Gorge Drive, Mast Boulevard, and the Grantville neighborhood of San Diego.

The project often involved night construction, street or lane closures and noisy bulldozers, but the project’s spokeswoman said while it’s received complaints when noise and drive-way blocking occurred, the predominant response has been good. “We did a lot of outreach to the community starting in 2022,” said Melissa McChesney. “People are generally aware of the project and I would say we’ve had an overwhelming positive response to the project.”

When it comes to the main treatment plant and the pipelines connecting to that and to the Lake Jennings reservoir, work is about 90 percent done, McChesney said. Other key facets of the project involve the upgrading of the Mission Gorge pump station, installing pipes connecting to the station, and a 7-mile brine line that connects to Mission Valley and San Diego’s sewer system.

The latter line, which will capture any sewage overflows during heavy wet weather, was the subject of a dispute between the AWP’s joint powers authority (JPA) and the city of San Diego in 2022 when San Diego dragged its heels over a prior agreement to sell the pump station. Frustrated at the constant delays, the JPA filed an eminent domain action in Superior Court, a highly unusual action when government agencies are involved. The settlement calls for the city to assume about 60 percent of the now $180 million estimated price tag for the brine line with the AWP paying the remainder.

The most recent $34 million amendment to Package 5 covers the final design and some construction of an energy recovery system at the main plant. It would convert biogases created from the solid waste to generate electricity for the plant. The power from the system  would be sufficient to cut the plant’s electrical cost by 20 percent as well as decrease its greenhouse gas emissions, said Director Mark Niemiec.

But the final price on this system isn’t known yet, and negotiations with contractors are still ongoing, Niemiac said. The total costs for the AWP haven’t always been clearly divulged as administrators tend to reveal costs in piecemeal fashion whenever a new phase of a package is proposed and approved by the JPA board.

However, in its most recent audit for the year ended June 30, it was disclosed the total cost for all five packages for the AWP, including reserves and contingencies, to be $1.2 billion.

That’s way up from the earliest estimate in 2015 at $500 million, and the $600 million estimate made in 2021. In the following year, the revised estimate was tabbed at $950 million, but that was surpassed earlier this year. There’s no telling what the actual, final sum will be when the system begins operating by the end of next year.

Officials at Padre Dam Water District have consistently said it’s all money well spent if the East County region is to secure some stability in water costs and maintain a more reliable source of water in the future. This takes on even greater importance in the face of ongoing negotiations among the seven Western states that use the severely depleted Colorado River due to decades long droughts and increased population. A temporary agreement reached in 2023 will expire in late 2026, and the states failed to meet a negotiating deadline earlier this month.

If the states can’t come to some agreement, the federal government could step in and determine how much water each state gets, said Niemiec. By building the AWP, the East County region would be in a better position in having a reliable water supply than if the region did nothing, he said.

And yet, even given the AWP’s promise of producing about 30 percent of the region’s need and selling water at 91 percent of the rate charged by the County Water Authority, customers’ bills won’t decrease, McChesney said. That’s because the costs for importing water will continue to rise, as well as inflationary increases on everything associated with delivering water.

Coincidently, the Padre Dam Water District, which has some of the highest water rates in the county, approved its latest annual rate hike to customer bills starting Jan. 1 that will cover the external increases charged by the CWA and SDG&E. McChesney said Padre Dam will not increase the rate it controls. She said the typical user will see the higher charges on their February bills of about 5 percent for most users in the western part of the district and 6 percent for those living in the eastern part, including Alpine and Harbison Canyon, Dehesa and Crest.