Will decades-old plant get new treatment at last?

Scott Swanson

City officials are watching costs skyrocket as they plan for a new wastewater treatment plant that, they say, is decades overdue.

But how needful, really, is a new plant in the first place?

Essentially, they say, Sweet Home’s plant is far too old, too small and too trouble-prone to continue to serve a city that’s growing in population.

Plus, although government environmental agencies have already cut it slack in regard to the nearly annual spillage of untreated sewage into the South Santiam River during heavy rainfall, the day of grace will not last forever.

City Public Works Director Greg Springman said the current plant is “extremely aged.”

“Most of the equipment is beyond its useful life,” he said. “Secondly, the capacity is undersized for the current community and for rainwater. In the wintertime we violate consistently, month to month, during heavy rain events.”

This is not a new discussion. It was in full swing in June of 2017 when Springman arrived, and it had been on the table for decades before that.

“During some of our research, we found a newspaper from Oct. 25, 1978, about the city having the same discussion about what to do,” Springman said. “How much do they build? They don’t have the funds. What will this do to ratepayers?

“Here we are, 40-some years later, having the same discussion.”

The city entered an agreement with the Oregon Department of Environmental Quality in January 2001 to address ongoing wastewater system overflows and discharge violations primarily caused by inflow and infiltration in the collection system, which is water that enters the sewer system through deteriorating pipes and cross connections with storm drainage.

The city spent some $15 million during the following 10 years in four phases to repair and replace sewer lines, reducing the amount of I&I entering the system, and city officials began seriously looking at plant upgrades to increase capacity in case of major weather events.

Costs on Rise

Over time, the price tag has gone up, particularly in recent months.

“We’ve seen the cost of the plant rise from an initial estimate of $28.2 million,” Interim City Manager Christy Wurster said. “And we are now seeing projections near $55 million; that includes the engineering costs.”

So where is the money coming from for a new plant and what do Sweet Home residents need to pay to make a new plant happen?

The city has already been awarded two grants from the state, totaling $9 million, for the construction project.

More recently, Wurster and City Finance Director Brandon Neish said, the city has been granted a $30 million EPA loan from the U.S. Department of Agriculture, which will provide money to get the project rolling.

City officials initially thought the money might be a grant, but that was due to unclear wording from the office of Rep. Pete DeFazio, who helped engineer financing. That turned out not to be the case, they discovered a few days after the announcement from DeFazio’s office, but Neish said the loan will “provide interim funding for us until the project is complete.”

“The USDA requires that you finish your project before they’ll distribute, so you need something to fill in the gap in the interim, because we don’t have $30 or $55 million in cash on hand. So DEQ, through the EPA will provide that interim financing for us until the project is complete.”

The cost to taypayers, over the 40-year duration of a loan, would be about $12.50 a month, Neish told the council on May 10. (See related story on page 1).

City Council members discussed the situation that day, voting to move forward with engineering designs for a new plant while the city waits to see if market prices go down.

Old, ‘Well-Past’

Steve Haney, Sweet Home’s utilities manager, noted that the current plant, located off Pleasant Valley Road across from White’s Park on the north side of the river, was constructed in 1947 and has had one major upgrade since – in 1974 and some minor improvements in the 1990s.

“Essentially, it’s a 1974 plant,” he said. “That’s 47 years ago.”

He said the 1974 upgrades were likely intended with a 20-year lifespan in mind – “maybe 30, but 20 is really typical.”

“So it was designed to last till 1994, and it really hasn’t had any major upgrades since then. We’re just well past.”

He said the plant is inadequate to meet the needs of the city’s current population, listed at 10,131 in the 2020 census. It had a population of 3,603 in the 1950 census and 3,799 in 1970.

“We’re just well past,” Haney said.

For instance, of the four variable frequency drives that pump sewage into the plant, one is so old that technicians won’t work on it, he said.

“It’s just waiting for a complete failure. There’s no repairing it, at this point. It’s just a full replacement, so we’re hoping that the new wastewater plant shows up before the failure.”

When a resident flushes a toilet, runs the garbage disposal, etc., the sewer water runs through pipes to the plant, where it is run through a “primary treatment,” starting with a device called a “comminutor,” which cuts up solids in the raw sewage in preparation for purifying treatment.

It then goes through processes to remove solids, which are transported to a landfill. The remaining liquid is then put through a “secondary treatment” that involves further settling and aeration of the effluent liquid before it is finally disinfected and discharged into the river.

The entire process uses gravity to allow solids to settle, in tanks called “clarifiers” and when the effluent becomes cleaner, it is aerated in other tanks that mix oxygen with the water to shorten the time needed to process the sewage.

At Sweet Home’s plant, Haney said, the clarifying tanks have holes “so big I could put my fist through them.”

Sewage, he noted, is not leaking through because the tanks are enclosed in concrete, but equipment used to suck material from the bottom does not function as well as it should.

Employees daily have to rake the screens that filter out large, non-treatable substances such as sanitary napkins, which fill buckets sitting alongside the tanks, several times a day. In the new plant, the current 1-inch screens will be replaced with quarter-inch screens that will be automated, Haney said.

The plant’s aeration basin uses motors that Sweet Home was able to acquire when Lebanon built a new sewer treatment plant, completed in 2019.

Before the treated effluent goes into the river, it’s run through sand filters, which are also too small and too old, Haney said.

The city has had ongoing issues with state environmental agencies as it has vented stormwater that includes raw sewage into the South Santiam River, due to the fact that the plant can’t process that volume.

“We’re only designed for a continuous capacity of 6 million gallons a day, a peak of 7,” Haney said. During the first week of May, “we were at 6 for a while and over 6. The plant just wasn’t designed for that.”

On May 6 the city had to discharge untreated sewage into the river, he said.

“We lost power, our generator wasn’t able to keep up because it’s undersized to run our facility. And we had a sanitary sewer overflow for approximately 4½ hours.

“Potentially, it wasn’t a lot, but we don’t have the telemetry. We don’t have the controls. We don’t even know how much went into the river, to be completely honest.”

New Plant Plans

The city contracted with Murraysmith engineering services in July of 2019 to produce plans and provide construction management services for the new plant, which will expand sewage treatment capacity from 7 mgd to 12.

Springman said the new plant will be built at the same location as the old one, with a slight expansion of the fenceline that borders the driveway from Pleasant Valley to the boat ramp.

The project will be completed in two phases, according to current plan. Phase I is expected to start this summer, with demolition, electrical and pre-work. Phase 2 will follow, depending on funding, hopefully with groundbreaking by June of 2023.

Springman said the cost of such a project is painful for small communities like Sweet Home, but it’s necessary. He said state and federal representatives and senators have communicated the need, and the city has been in regular contact with the DEQ, which has held off on fines “but we will be if we don’t conform at some point.”

“The ultimate goal of state or DEQ fines is to be a carrot to get us to do what we need to do,” he said.

“We want to be good neighbors to our neighbors downstream and to the environment by controlling organic materials going into the river.

“We want people to come to the South Santiam and fish and raft and take part of the river that’s outside of our community. We don’t want to have issues. Building this plant will allow us to efficiently and consistently achieve compliance.”