December 26, 2010 in City

Spokane’s sewage system undergoing quiet upgrade

Next phase: storage tanks to catch overflows of rain and snowmelt
By The Spokesman-Review
 
Jonathan Brunt photo

Untreated sewage and storm water flow into the Spokane River under the Monroe Street Bridge on Dec. 15. The city has about 30 pipes that release sewage into the river during rain or snowmelt.
(Full-size photo)

Fast facts: Before the city’s overflow tank program began, the city’s sewer system dumped about

80 million gallons of raw sewage into the Spokane River annually during rain and snowmelt. That’s about two days’ worth of sewage that arrives daily at the city’s sewage treatment plant.

When it rains in Spokane, it pours sewage into the Spokane River.

Faced with a 2017 deadline to stop discharging millions of gallons of raw sewage annually into the Spokane River, the city in 2011 will build several underground tanks to help stem the flow – although the biggest and most expensive projects won’t be completed until much closer to the deadline.

Before the city began pursuing its latest strategy to keep untreated wastewater out of the river more than a decade ago, an average of about 80 million gallons of sewage a year flowed to the river during rain and snowmelt.

The city already has stopped the flow from six overflow pipes by building tanks to store wastewater when sewers get overwhelmed. The wastewater then is piped back into the system and treated when capacity is available. 

The early projects were smaller – although the city estimates that 4.4 million gallons a year on average is diverted to the treatment plant from the overflow pipes.

Next year, the city will finish projects to capture an additional 5.7 million gallons from six overflow pipes.

To Lars Hendron, the city’s principal wastewater engineer leading the project, the numbers signal progress.

“We’ve been taxiing for a while, and now we’re just about ready for liftoff,” he said. “There is a definite ‘yuck factor.’ Citizens expect to be able to use the river knowing that there’s hardly ever any sewage in it.”

But the solution comes with an estimated $300 million price tag that is coupled with steep jumps on utility bills. Just last week, the Spokane City Council approved a 17 percent boost in sewage rates to help pay for the overflow prevention system. 

Besides the city’s hefty 20 percent utility tax, the rates also will help finance a separate program to improve treatment at the city’s plant. The increase was on top of a similar hike last year, and more double-digit increases are expected in the next few years. Even with larger revenues from bills, the city still expects to borrow money to finish the upgrades.

Mayor Mary Verner said she is committed to completing the program but has asked state leaders to consider extending the deadline to help spread out the cost.

Richard Koch, senior environmental engineer for the state Department of Ecology, said the state has no plans to change the Dec. 31, 2017, deadline, which is included in the city’s permit to discharge wastewater.   

“At the current time, we’re saying, ‘No way,’ ” Koch said. He added, however, that if in a few years the city has made significant progress and has a clear path to finish, the state might be willing to reconsider. “The city is correct to be concerned about cost,” Koch said. “Yet this is the cost of maintaining the environment, which is one of the main selling points of Spokane.”

The city’s permit says that as of the end of 2017 each of the city’s overflow pipes will be limited to one overflow per year from rain or snow melt. Currently, the city’s most active pipe overflows about 50 times.

Next year, homeowners in Spokane will pay $43.73 a month for sewer service. Koch noted the cost in some rural parts of the state is well over $80.

Councilwoman Nancy McLaughlin, who voted against the wastewater rate increase, said she supports the upgrades to keep sewage out of the river but believes residents can’t afford the spikes.

“That’s important work that we’re doing, but we need more flexibility,” she said. McLaughlin also criticizes the state and federal governments for setting strict rules while providing little money to complete upgrades.

Rachael Paschal Osborn, executive director of the Center for Environmental Law and Policy, criticized any request to extend the deadline.

“It’s really time to get the raw sewage out of the river,” she said, noting that the city was given nearly two decades to achieve the goal. “It was plenty of time to figure it out, how to fund it and get it done.”

Some critics note that the city would have more money to complete the projects if it didn’t divert 20 percent of rates for utility taxes. Verner and the City Council decided a couple years ago to begin taxing rates devoted to capital projects, which previously weren’t taxed.

Spokane and other cities have lobbied the state Legislature for help meeting the environmental rules for sewage. 

State Rep. Timm Ormbsy, D-Spokane, sponsored a bill earlier this year that would have raised fees on petroleum in part to help finance municipal sewer projects like Spokane’s. Ormsby said he expects the issue to be discussed again next year, though it’s unclear if there’s much chance of approving fees or taxes to pay for sewage upgrades given the anti-tax sentiment voters expressed in November.

“I felt that it was a shared public responsibility because all of us collectively have an interest in water quality,” Ormsby said.

Koch said dumping raw sewage into the river is a public heath concern and adds phosphorus to the water, which contributes to toxic algae blooms in Lake Spokane.

Spokane’s problems with sewage overflows are similar to those in many cities that have sanitary sewers connected to storm water systems.

In the 1930s, the city pooh-poohed state officials who criticized Spokane for not treating its sewage before dumping it into the river. Treatment didn’t begin until the 1950s. Because the storm water flowed into the sewers, pipes directly to the river remained so that when the system was overwhelmed sewage could go into the river to prevent backups.

In the 1980s, Spokane separated storm and sanitary sewers so that rain could be piped to the river without affecting sewage. Much of Spokane’s North Side has separate sewers for wastewater and storm water. 

But because of more stringent rules on dumping storm water into the river, Spokane shifted its strategy in the 1990s to building overflow tanks.

Hendron, the wastewater engineer, said much of the past decade was spent planning for the tanks and learning from them so the city can better plan the larger ones. 

“We also knew we would have quite a learning curve,” Hendron said.

While the city’s main strategy is building tanks, the city also has constructed other kinds of systems in hope of reducing storm water flow so that future tanks can be reduced in size. The largest tanks are expected to hold 5 million gallons – enough to roughly fill eight Olympic-size swimming pools.

In some areas the city has redirected storm water to flow into the ground. One high-profile project completed this year on Lincoln Street on the South Hill captures rain and takes it to a pond in Cannon Hill Park.

“While we’re doing the gradual build-out (of tanks), we’re also exploring and building other innovative storm water catchment,” Verner said.

Councilman Jon Snyder said he believes the city is on the right path to solving the problem even if improving the sewers isn’t as popular as building roads or bridges.

“Sewer infrastructure is often the forgotten aspect of infrastructure.” Snyder said. “No one wants a combined sewage overflow tank named after them.”


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