The City of Moab is planning to replace its existing wastewater treatment plant on 400 North with a new facility just across the street. [Moab Sun News file photo]

The odors that waft up from Moab’s wastewater treatment plant aren’t pleasant at times, but city officials say they pose no direct threats to human health.

“I admit it’s a nuisance, but I’m not aware of any health concerns that could come from this sort of odor,” Bowen Collins engineer Jeff Beckman said during a Feb. 23 Moab City Council workshop on the issue.

Wastewater treatment operators currently add ferric chloride to the material they process in an effort to keep the odors under control. That hasn’t always worked, but Beckman suggested that in the short term, at least, the city could address the problem by adding the same chemical during another phase of the treatment process.

The city is about one-third of the way through the design phase for a new treatment facility, which could be up and running by mid-2018, according to Moab City Manager Rebecca Davidson.

But until that date actually arrives, county resident Bill Love is urging the city and county councils to place a moratorium on future construction, arguing that smells from the existing plant may be affecting human health.

Love said he believes that officials have increased the severity of the odor problem by approving “hundreds” of apartments, hotel rooms and restaurants that are now under construction. That problem could only grow, he said, if developers are allowed to pursue plans for hundreds of additional units.

“The promise of a new plant sometime in the future is not sufficient to protect the health of the residents today,” he said in an open letter to city officials. “The current problem may reach a crisis when hundreds of new apartments, hotel rooms and restaurants under construction will open in 2016 or 2017.”

Moab City Engineer Philip Bowman said the strong odors that residents in surrounding neighborhoods smell on occasion are associated with the sewage treatment process. While they’re admittedly a nuisance, he said, they are not harmful.

At the same time, Bowman rejected Love’s allegations that the city is dumping raw sewage directly into the Colorado River and the Matheson Wetlands during the visitor season, when volumes flowing into the treatment plant are at their highest.

“That is not true – that is not happening,” he said.

According to Bowman, the city is releasing treated effluent into the river, as it’s allowed to do under the terms of its state discharge permit.

At certain times of the year when the river is running at high volumes, the pressure builds up inside a pipe that carries the effluent, causing a manhole cover at the wetlands to pop off, he said.

In those cases, Beckman said that treated water may spill out onto the Matheson preserve.

Moab Mosquito Abatement District Manager Bob Phillips said he believes that any discharges at the wetlands pose significant harm to the environment.

“(The) evidence suggests that much of the fish kill that occurs in the Preserve during high river is caused by this undiluted, deoxygenated, and chlorinated sewage effluent,” he said in an email to Love.

Moreover, Phillips is concerned that the discharges could lead to an increase in pest mosquitos, as well as a heightened risk of mosquito-borne diseases.

Bowman said that officials are committed to solving the problem.

Beckman said the city is eager to get started on site preparation work for the new facility, which will be located near the corner of Stewart Lane and 400 North just across the street from the current plant.

“We want to get this going as fast as possible,” he said.

Although the existing 1950s-era facility is doing what it was designed to do, Beckman said that total suspended solids and biochemical oxygen demand levels have climbed over the years.

“The problem we have (is) it’s slowly increased, and that’s pushing the treatment plant to its capacity,” he said.

In addition to processing wastewater from within the city limits, the facility handles highly concentrated septage from private haulers and public land management agencies. Concentrations in that foul-smelling stew of materials can be 80 to 100 times higher than regular wastewater flows, and with more and more septage arriving each year, Beckman suggested it could be contributing to the facility’s woes.

“You just look at the load coming in, and yeah, it could be part of the problem,” he said.

In the short term, Beckman suggested that the city could take steps to ensure that septage doesn’t come in at once, and then just sit at the facility for days at a time.

Looking further into the future, Davidson said that final design work on the new treatment plant should be done by the fall of 2016.

Once the city awards a bid for the construction phase of the project, she estimates that it will take contractors about 16 to 18 months to build the facility. Davidson predicts it will have a 20-year lifespan; future additions could extend the new plant’s operating life for another 20 to 30 years.

“We’re trying to get a 50-year life out of what we’re developing right now,” she said during a joint city and council workshop on Monday, Feb. 29.

The new facility will operate as a regional treatment plant, much to the relief of state officials.

“They don’t want sewer plants all over the place,” Davidson said. “So it’s very important for us to work with people that are in our area. That could be San Juan County at the upper end; that could be – and is – the National Park Service and (U.S. Bureau of Land Management) related to septage hauling, and there’s private haulers that push their material to us. And then, of course, there’s our own.”

Davidson estimates that it will cost about $11 million to build the new facility; the city is turning to the state for the bulk of that up-front funding. Later this month, they plan to ask the Utah Division of Water Quality for a $10 million loan, which could be paid off after 20 years.

To help cover the project’s costs, Davidson said that ratepayers can expect to pay more for the sewer services they use – assuming that the council approves recommendations to increase their monthly bills.

“I think we’ll see another 20 percent request from staff to council in July, and then there will be another increase next year in July,” she said. “We think those will bring us up to par.”

However, the city is not undertaking the project on its own, and Davidson said officials want to ensure that the construction and development costs are distributed fairly, so that every entity is footing the bill.

“In prior years, I think the city carried more of the load, from what I’m able to determine, and now, we want the city to pay (its) fair share, but not be carrying the load,” she said.

Officials work to minimize smell as design of new facility continues

I admit it’s a nuisance, but I’m not aware of any health concerns that could come from this sort of odor.