Upgrading Sacramento’s wastewater treatment could cost $2 billion

Some jokingly call it the Big Flush.

Officials at Sacramento’s immense wastewater treatment plant intend to begin construction this year on what could be the largest public works project in Sacramento County’s history – an expansion they say will cost between $1.5 billion and $2 billion.

The Sacramento Regional Wastewater Treatment Plant, near Elk Grove, needs major upgrades after state water authorities determined it was discharging too many pollutants into the Sacramento River, threatening public health and harming aquatic life in the Sacramento-San Joaquin Delta.

The sanitation district, which operates the plant, challenged those findings in a lawsuit. But on Friday it agreed to settle the last of its claims, dropping the lawsuit and moving forward with the massive upgrade to its treatment facilities.

Only a few recent public works projects in the capital region have carried anywhere close to such a huge price tag. They include the construction of a new terminal and jet concourse at Sacramento International Airport, known as the Big Build, the strengthening of Natomas basin levees, and a new flood-control spillway at Folsom Dam. Each cost about $1 billion. Major highway improvements, such as the Big Fix of Interstate 5 in 2008 and today’s Fix50 project, cost only a fraction as much.

Unlike other large-scale efforts, the changes at the treatment plant will be mostly invisible to the public. Roughly 1.4 million customers in Sacramento County and West Sacramento will see their sewer bills rise in coming years, but they won’t experience different service or witness the process, unless they sign up for a tour.

Built in the late 1970s, the treatment plant was the largest public works project of its time in Sacramento County. Today, it’s one of the region’s least-known infrastructure giants, employing 350 workers and operating every day, around the clock.

“For most people, it’s generally out of sight, out of mind,” said Prabhakar Somavarapu, district engineer and head of the treatment plant. “But when you’re asking people to pay greater rates, they want to know where you are and what you do. Outreach is important.”

Sanitation officials launched a public awareness campaign last year. To overcome their awkward name – the Sacramento Regional County Sanitation District – they adopted a nickname, Regional San, hosted a series of plant tours, and created a motto: “Regional San: Taking the waste out of water.”

“We’re trying to be more approachable,” said district spokeswoman Claudia Goss.

They dubbed the massive upgrade project “EchoWater,” to evoke “bringing water back to its natural state, like an echo,” said Somavarapu. Plus, he added, smiling, it sounded better than “the Big Flush.”

Sanitation authorities also hope the project will allow them to raise revenue by selling billions of gallons of highly treated wastewater to farmers in southern Sacramento County and a power plant at the former Campbell Soup factory in south Sacramento.

Discharge posed risks

To understand how things got to this point, it helps to go back to the early 1970s, when Congress passed the Clean Water Act. At that time Sacramento County was still served by 22 smaller treatment plants scattered along the American and Sacramento rivers. Some discharged untreated or partially treated sewage into the rivers, fouling the water downstream.

Sacramento County, the city of Sacramento and Folsom teamed up to create the Sacramento Regional County Sanitation District. They eventually won a federal grant of $450 million to build a treatment plant and pipelines that could serve the needs of the county and beyond. The whole project cost more than $500 million, Somavarapu said.

They bought about 3,400 acres from farmers and other landowners in the south part of the county, providing plenty of room for the plant and a large rural buffer from its nearest neighbors to reduce odor complaints and provide wildlife habitat. Construction began in 1976, and the plant went online in 1982.

The estimated price of fixing the sewage plant reflects its enormous scale. Sprawled across 900 acres, it looks like the set of a 1970s science fiction movie, with vast plains of concrete, windowless towers and miles of underground passageways. Guards, gates and video cameras protect the facility. The region could be crippled if it went out of service.

More than 175 miles of transmission pipelines, some 12 feet across, link Sacramento, Elk Grove, Rancho Cordova and other communities to the plant. It handles about 150 million gallons of wastewater each day. The treated water then flows into the Sacramento River through an outlet near the Freeport Bridge.

In December 2010, the Central Valley Regional Water Quality Control Board told the plant to clean up its effluent as a condition of renewing its state discharge permit. The board found that high volumes of ammonia in the water were disrupting the food chain and endangering fish such as salmon and Delta smelt. Single-celled organisms posed health risks to people who came in contact with the river water, board members concluded.

The board ordered the district to reduce those pollutants by instituting additional layers of filtering and disinfection known as “tertiary” treatment, the highest level under state law. It gave the sewer agency a decade to comply.

The sanitation district’s board, made up of elected officials from around the region, fought the order for years. It appealed to the State Water Resources Control Board, claiming the regional board had failed to back its order with adequate science and saying the upgrades would be prohibitively expensive to ratepayers at a cost of $2 billion.

It also filed a lawsuit in 2011 against the regulators. The district settled part of the case in April 2013, agreeing not to fight the terms of the permit that required it to remove ammonia and to meet a deadline of May 2021. The district plans to use bacteria in open-air tanks to break down ammonia in the wastewater.

On Friday, officials from the sanitation district and water board announced they had agreed to settle the second part of the case, involving requirements that the district filter out the pathogens giardia and cryptosporidium, which can sicken humans.

The compromise agreement requires the district to filter the vast majority of wastewater flowing into the plant, but not all of it. That will reduce potential harm while saving a large amount in construction costs, both sides said.

“If our board adopts the settlement, and no one appeals, the district will drop its lawsuit,” said Ken Landau, assistant executive officer of the regional water quality control board. “It will save them about $100 million.”

A district pilot program showed that filtering wastewater with sand and anthracite coal, a relatively inexpensive method, effectively removes most of the parasites. The process will save an additional $200 million over more costly methods, Somavarapu said.

‘Embrace the water’

Even with those reductions, the project will cost at least $1.5 billion, he said. Ratepayers will ultimately foot the bill. The district expects its customers’ monthly sewer rates, now $26 for a single-family home, to potentially double by 2023. There will be gradual increases along the way. A $3 monthly rate hike is scheduled for July.

The district also is looking at ways to raise revenue by selling more recycled water to commercial and government customers. Under state law, wastewater that undergoes tertiary treatment can be used for watering lawns, irrigating crops and cooling power plants.

The plant already has a small, outdated unit that can produce about 3 million gallons of recycled water per day, which it sells to the Sacramento County Water Agency to irrigate school lawns and parks in Elk Grove.

“When we upgrade the plant in seven or eight years, our entire output is available for recycling,” Somavarapu said.

In anticipation, district officials are working on plans to pipe water 6 miles north to the Sacramento Municipal Utility District’s cogeneration facility at the former Campbell Soup plant in south Sacramento. The power plant could use about 365 million gallons a year for cooling, the district estimates. The recycled water would replace the drinkable water the power plant now uses.

Another plan is to pipe water south to farmers growing alfalfa and other crops. The district’s South County Ag Program could provide up to 12 billion gallons per year to irrigate farm fields in southern Sacramento County. Farmers now use groundwater, depleting underground aquifers. Running pipes to the area could cost about $175 million, district officials say.

Ken Oneto, a south county farmer and board member of the Sacramento County Farm Bureau, said farmers might buy recycled water if it cost about the same as pumping groundwater and didn’t raise health concerns.

“It makes more sense to use that water than groundwater, which is a real precious commodity,” Oneto said. “I think everybody around here would embrace the water if the price was comparable.”

To sell recycled water, which the plant would otherwise be putting back into the Sacramento River, the district would have to get permission from the state Water Resources Control Board, Somavarapu said. The plant is the largest inland discharger of water in the state, replenishing flows to the depleted Delta, so permission to divert its output isn’t guaranteed.

But officials said they think the appeal of using recycled water in place of drinking water or groundwater may win the day. The district now sells methane gas, a byproduct of waste treatment, to a neighboring SMUD power plant. An on-site contractor turns dried solid waste into fertilizer pellets. Recycling water is the next big step, Somavarapu said.

“Sustainability is part of our fabric,” he said.