With groundwater supplies in dwindling supply and questionable quality, members of the Stanislaus Regional Water Authority (SRWA) acted formally on Thursday to start the process of building a plant to deliver treated Tuolumne River water to homes in Ceres and Turlock by 2022.

The SRWA is a joint powers authority with a board comprised of two members of the Ceres City Council and two from the Turlock City Council.

On-again, off-again talk of building a surface water plant for the two cities dates back three decades with plans falling apart over raw water costs. Turlock Irrigation District and the JPA reached an agreement on raw water costs. Now the only thing that could spoil the plan is a proposal of the State Water Resources Control Board to take more water from Don Pedro Reservoir. The board has yet to make a decision on the so-called Bay-Delta Water Quality Control Plan, which could result in a 40 percent unimpaired flow out of Don Pedro.

The SRWA board met at Turlock City Hall on Thursday and received a report that detailed the plant will be sized to siphon and treat up to 15 million gallons per day (mgd) for use in the two cities. Both Ceres and Turlock would blend the new source of water with treated groundwater. Turlock could receive up to 10 mgd while Ceres has a claim of 5 mgd. Construction of the plant will cost $288 million with Turlock paying $182 million and Ceres $100 million.

To cover expenses, both cities will need to raise water rates under the protest hearing outlined in Prop. 218. A rate analysis is being conducted so the preliminary numbers offered at the meeting may not prove accurate.

Ceres projects that the average monthly water bill would be $51 in 2020 with no surface water plant constructed. With the plant, rates are expected to be $27 higher, or $78 per month by 2020.

In Turlock the average water bill is expected to jump from $43 per month in 2018 to $54 in 2020 without a surface water plant. With the plant water rates would be driven up by $26 per month, to about $83 per month by 2020.

"When we are out talking to our residents ... about this topic, yeah you'd like to have cheaper water rates but they're going to up regardless and so we have to look at the cost of what brings up reliability," said Turlock Mayor Gary Soiseth. He pointed out the newer water rates will be on par of what communities in the Valley are already paying. "Our rates have been artificially low for a very long time."

Ceres Mayor Chris Vierra said the plant is a necessity for a guaranteed source of clean and reliable water.

"I think the do-nothing alternative is really not an option," said Vierra. "The requirements for our drinking water quality gets ratcheted tighter and tighter."

Ceres City Councilman Ken Lane who sits on the board said the cities will benefit from the action.

"In the long run it's going to cost a lot more if we stay on the same avenue," said Lane.

Ceres City Manager Toby Wells said both cities want to break its 100 percent reliance on groundwater for two main reasons.

"As we all saw through the drought, that becomes very difficult to manage and that drought has impacted our groundwater levels as well as water quality changes ... that come from federal and state regulations changing," said Wells. "Those water quality challenges continue to get worse and worse."

Wells said Ceres and Turlock are dealing with the same water issues.

Ceres as 12 active wells but new regulations for Trichloropropane (TCP) will affect seven of the wells and trigger more costly treatments. He explained that the water table is about 64 feet below the surface of the ground but that the pumping level has dropped 40 feet.

"It's taking a lot more work to get that same volume of water out of the ground and we're pulling from a much deeper strata of water which is leading to some different water quality than we've seen in the past."

It's been a challenge for the cities to deal with naturally occurring levels of arsenics, nitrates and uranium with wellhead treatment running $1 million to $2 million.

Michael Cook, director of Municipal Services for the city of Turlock, said his city has 17 active wells but had to remove 22 wells from active service in recent years.

"We're constantly struggling with water quality, water quantity, which makes reliance on groundwater increasingly challenging," said Cook.

He said that water sampled from a well near Wakefield School this week shows such a dramatic increase in nitrate levels that it could soon exceed state standards.

"I kind of liken it to Whack-a-Mole," said Cook. "Just when you think you're ahead you get knocked back down again. It's a constant battle."

Six wells in Turlock could face abandonment next year or expensive treatment thanks to more stringent state standards on TCP.

To get by for the interim, Turlock is trying to rehabilitate and rehabilitate wells but they will be incapable of producing the same quantity of water as years ago. The city is also drilling five new test wells.

Added benefits to the surface water system, said Lindsay Smith of West Yost Associates, will be less pumping of the groundwater supplies to allow for a more rapid recharge.

"There's also the environmental benefit to the Tuolumne River aquatic species because we will be providing more water in the Tuolumne River in the 26 miles between the La Grange Dam and where we're diverting water to this project (at Fox Grove)," said Smith.

An added benefit will be reduced hardness and mineral content for households and wastewater discharge.

Smith said the plant will give both cities the potential to offer water to other communities, like Denair and Hughson, or disadvantaged communities.

With an infiltration gallery in place in the river bed on the south side of the river west of Geer Road, the next step will be construct a wet well and pump station. Water will be piped underneath the Geer Road Bridge to a treatment plant that will be situated southeast of the Fox Grove Fishing Access parking lot.

Ceres will receive water through a five-mile 24-inch water line to be constructed down Hatch Road to an above-ground tank to be constructed at Ceres River Bluff Regional Park. A seven-mile water line will be constructed down Berkeley Avenue to Turlock, which will also need to install new pipes along N. Quincy, Canal Drive and E. Taylor.

A majority of the project will be financed by a 30-year loan from the Drinking Water State Revolving Fund (SRF). Currently the state offers a 1.9 percent interest rate. The agency will also pursue a number of grant opportunities.

The SRWA recently lobbied for passage of special legislation in SB 373 which enables the agency to construct the plant using a design-build delivery method. Such a method enables the plant to be built faster and cheaper than the alternative.

Gerry Nakano of West Yost Associates said environmental work is continuing and appraisals have been completed for the purchase of land needed for a wet well.

He also noted that the agency is in the process of hiring a general manager.