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| What alternatives are there to city’s wastewater plan? |
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| For FMR, wetlands may or may not be the alternative |
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By Jerry Raehal
Mark Schmidt is not afraid to say that the Friends of the Molalla River are dreamers and idealists.
As a spokesman for FMR, he knows it’s the group’s dream to keep the city of Molalla’s wintertime discharge of effluent — municipal sewage treated at the wastewater plant — out of the Molalla River.
And ideally, FMR has promoted the way to do that with a wetlands system that would polish the city’s effluent and allow continued discharge to Bear Creek.
At least that was the thought until recently.
“I think what happened is that people got on the wetlands bandwagon because it is popular, and away they went, and I’m encouraging our group and the community at large that there are maybe other technologies,” Schmidt said. “That maybe wetlands are or maybe wetlands are not the right technology, and to make sure that our Friends and the community at large is not grabbing onto a dream that may not be real.”
Despite the possible change in stance, Schmidt still “feels secure that our engineers are going to be able to keep us out of the Molalla River if the vote comes down.”
The vote he speaks of is on the Sept. 19 election, with ballots going out Sept. 1. A yes vote would amend the city charter prohibiting the city “from discharging any treated or untreated sewage into the Molalla River,” according to the Ballot Summary. “... The measure attempts to prohibit sewage discharges at an outfall location into the Molalla River otherwise allowable under a state administered federal discharge permit.”
The city of Molalla is scheduled to start winter discharge into the Molalla River in November, per its permit with the Department of Environmental Quality.
In the summer, the city has used the reclaimed water to irrigate Steve and Kathy Coleman’s Ranch for the past couple of years — a part of the plan that FMR is in favor of, at least in theory.
‘Pipe dream’ not dead
Also in theory, the Friends of the Molalla River haven’t given up its “pipe dream” of a wetlands, though Schmidt admits other options might be better. One reason for the change in heart, as well as Schmidt’s optimism of a different alternative, is recent meetings with new engineers.
“The (city’s) current plant really isn’t all that bad,” he recalled the engineers telling him. “The facilities that we have, have been developed properly, and the technology that we are using is what is conventionally used in the area to do the same things as cities our size. So as we look at the overall plant, they say, ‘Until we can get inside and look at how it’s being managed and handled, and look at the bottlenecks in the system,’ it’s impossible for them to be any more definitive.”
He noted that engineers weren’t sure why the city’s plant was having problems with Biological Oxygen Demand (BOD) and ammonia — two reasons DEQ has noted as limiting factors in regards to continue discharge to Bear Creek.
Gary Sage, an environmental specialist with DEQ, was skeptical about adding new treatments to Molalla’s plan.
“Additional treatment beyond tertiary (now practiced at Molalla) would be unconventional, i.e. experimental/not common practice,” he wrote in an email. “City could conceivably add ozonation unit to final effluent to reduce BOD5 and ammonia. The life-cycle cost for operation and maintenance of an ozonation unit is unknown.”
In addition to BOD and ammonia, other FMR concerns with the city’s plan include endocrine disrupters — or pharmaceutical active compounds — and chlorine, among other.
Other wetlands
Over the past couple of months, FMR has cited several cities’ plants as examples of wetlands systems that Molalla can try. The issue with wetlands is various cities use them for different treatment issues.
The cities of Silverton, and Woodburn — which is in the process of proposing one — either use or will use their wetlands system for temperature control, with no other function in the treatment process, before discharging into their respected creeks/rivers.
The city of Cannon Beach was one of the first cities in Oregon to use a wetlands system, starting in 1984. It is in the process of updating its wetlands system because of ammonia problems.
“The wetlands will not help (with that),” said Joy Gannon, Cannon Beach public works director, noting their wetland system is used to polish up BOD and for lowering temperature. “We actually did a study on that, and ammonia is one of the main driving factors for the city’s upgrade — the ammonia toxicity with the fish.”
Gannon and Steven Starner, city of Silverton water quality supervisor, both note that wetlands can make excellent parks and/or tourist attractions.
A possibility
However, there is one wetlands example that FMR member Bill Taylor said might meet Molalla’s needs — the Willow Lake Wastewater Treatment Plant, which is a Natural Reclamation System (NRS) demonstration project for the city of Salem.
Stephanie Eisner, NRS project coordinator, said there is a difference between Cannon Beach and the NRS project, one being that Cannon Beach was done in a natural occurring wetlands — a practice the EPA has moved away from.
“Also what we’re doing different is that we just don’t have the wetlands. We have the overland flow and vertical flow,” she said.
With those two extra treatments in place, the pilot project is able to remove ammonia through a process called nitrification that can’t be done in a wetlands system alone. Eisner also pointed out that the plant also helps lower BOD numbers, though at the Salem plant, she noted BOD numbers are very low before it gets to the NRS portion. Those “low numbers” in the winter “are around a 7 or 8” BOD parts per million. The Molalla plant averages a 4 BOD parts per million, and its permit is set for 10 BOD.
Sage points out finding technology that would lower Molalla’s BOD enough to continue discharge into Bear Creek is unlikely.
“If they have to discharge to Bear Creek, we would have to write very strict limits into the permit, including ammonia at practically nothing and a BOD at 2 or less,” he said. “And that would be the limit, and the actual treatment plant would have to do better. Let’s say the permit said 2 milligrams per liter of BOD, then the treatment plant would have to be designed on average to produce a constant rate of 1.
“I guess there are some exotic things that you can do (to get down to 1 MGD),” he said, noting he was unaware of any such treatment.
Wetlands and the winter
To process the Willow Lake Wastewater Treatment Plant’s maximum of 1 MGD limit, the project uses less than 10 acres for treatment area. There is another 15 acres surrounding the plant. Cost for the whole project — including the 15 surrounding acres, which is used as a public park with walking trails — was $3.6 million.
According to a memorandum produced by the Molalla Public Works Director Dean Madison, the city of Molalla Wastewater Treatment Plant is capable of treating an average wet weather flow of 1.92 MGD, nearly twice the amount of the Salem project. With future upgrades, the city will have the capability of doing 3.0 MGD.
Eisner believed that the difference could be made up by having a larger wetlands treatment area, but that there could be problems with the winter time aspect of the discharge. She said that the wetlands system still can have some benefits during the winter months, but the cooler temperatures make the system not as effective, noting that the city of Salem uses the NRS for extra overflow storage in the winter. She estimated the effectiveness of reducing ammonia and BOD goes down by 10-15 percent “off the top of my head.”
A wetlands system used for winter discharge has limitations, according to Ralph Rogers, regional wetlands ecologist with Environmental Protection Agency, noting wetlands tend to work better in the summer.
BOD and ammonia wintertime reduction numbers are important for the FMR as DEQ has cited those factors as main reasons why the city of Molalla cannot continue to discharge into Bear Creek. FMR has argued that if treatment at the Molalla plant was improved, the city of Molalla could continue treating to the stream and revitalize it.
“If they’re looking at it for a winter treatment, it is probably going to have be designed differently than our system was designed because our system was designed to deal with ammonia and temperature during the summer,” Einstein said.
And while Schmidt acknowledges that a wetlands system may or may not be a system that his engineers believe could work in the Molalla, the engineers he’s talked to make him believe there is still a cost effective solution.
“I’m saying that there are alternatives out there that will fall well within the budget that we have established from everything that everybody has pointed to,” he said. “That being said, my uncertainty is that I don’t feel qualified to dictate to our future design engineers where we go with alternatives.”
(In Wednesdays Pioneer — The final part of the series. To review all previous articles in the series, visit www.molallapioneer.com)
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