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| What alternatives are there to city’s wastewater plan? |
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| City releases cost of several alternatives |
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By Jerry Raehal
What’s it going to cost?
During the debate over whether Molalla citizens should vote to stop wintertime effluent discharge from going into the Molalla River, that question has been asked several times.
The lone estimate on the cost of a new treatment plant or plan was $35 million, though there was much debate about that number.
On Tuesday, the Molalla City Hall, in a written statement by City Manger Gene Green, released more possible sanitary sewer disposal options and their possible monetary costs, not including maintenance and operation costs or permitting costs.
All options except one would increase sewer rates, ranging from $15.58 per month to $103.24 per month.
Tom Derry of the Friends of the Molalla River disagreed that a solution would cost more than the city is already planning to spend on upgrades.
“We know that our solution is not going to increase the sewer rates. The experts are telling us that if they did the alternatives that we are recommending that it wouldn’t cost anymore,” he said.
Given that FMR might or might not be moving away from a wetlands option, Derry, could not give an estimate on what the cost of any FMR alternatives might be.
Alternatives
• The first one listed is continued discharge to Bear Creek.
“Our revised calculations estimates an average wet weather flow (AWWF) of 3.01 Million Gallons per Day (MGD) in 2025, the end of the planning period,” the statement read. “Further review of our historical records of flow in Bear Creek, (November 2000 through April 2005) was only 6.5 MGD, giving a 2-1 dilution ratio, at best, with seven of the 30 discharge months having a flow of only 3.0 MGD. It is highly unlikely that DEQ would allow any substantial discharge to Bear Creek, given those numbers.”
• The most costly option listed was an alternative for exclusive summer irrigation with no river discharge.
“Under this alternative, treated effluent would be stored during the winter, non-irrigation season, at storage ponds located near additional irrigable land,” the statement read. “Treated effluent from these ponds as well as directly from the treatment plant would be applied to pasture land, nursery stack and silage throughout the irrigation season. This option would require 180 acres of land for new ponds, plus another 800 acres for irrigation. As there are few large places near the treatment plant, it is assumed that 10 ponds, each supplying water for 80 acres, would be constructed. An irrigation pump station and irrigation equipment would be needed at each location. Underground piping from the treatment plant to each pond would be required.”
According to the statement, costs for the irrigation pipeline would be $1 million, plant improvements would be $2.1 million, and the irrigation system including land would be $36.1 million for a total. Not including other costs, this option would increase rate payers bills by $103.24 per month.
“They would have to build their lagoons bigger, and they would have to work the water balance out,” said Gary Sage, environmental specialist with the Department of Environmental Quality. “They would have to be able to store everything, including rainfall in the winter ... and they would have to increase acreage for irrigation.”
• The Willamette River Discharge would take the city’s effluent an estimated 20 miles out of city limits, according to the statement, and is technically feasible.
“It would require at least one intermediate pumping station, a discharge monitoring structure, some means of aeration and a river outfall. No right of way acquisition costs are included.”
Cost for the pipeline to the Willamette (includes outfall) would be $16.8 million, while plant improvements would be $2.1 million for a total projected cost of $18.9 million. Not including O&M, this option would increase costs to the rate payers by $27.38 per month.
“They would have to buy easements through certain areas, they would have to bore under certain creeks and ponds,” Sage said. “It would not be cheap, that’s for sure.”
• Tom Derry of the Friends of the Molalla River said the city’s next listed option, Bear Creek discharge with enhanced flows, was generated by his group.
“That was one of our ideas — pulling water out of the Molalla River and subsidizing the flows to Bear Creek,” he said. “They have a water line, and they have a water plant down there right now, so they could contribute to the flow of Bear Creek, and possibly meet the dilution requirements that way, between that and cleaning up the water more.”
According to the statement, “This option would entail securing a winter time only water permit for the Molalla River for at least 10 MGD, building a pump station and pumping that 10 MGD a day back into Bear Creek at some point upstream from our existing treatment plant with the object of increasing flows in Bear Creek enough to allow continued wintertime discharge. This would take numerous permits and approvals from various state agencies, but at least is technically possible. This option would use the existing irrigation pressure main as a pipe line back to Bear Creek and with water from the Molalla River used to enhance flows.”
The cost of the intake and pump station would be $3.8 million, plant improvements would be $2.1 million for a total of $5.9 million. This option would increase costs to the rate payers by $15.58 per month.
“It doesn’t make a lot of sense to do that,” Sage said. “I know they do that for drinking water programs ... but why do that with all of the political and administrative hurdles are considerable to divert flows from the Molalla. (It) might mean they would be pumping fish out of the Molalla at some point, unless they had some really good screens.”
• An additional option to the Bear Creek discharge with enhanced flows would be converting treatment plant to add an activated sludge treatment.
“This is the same option as above, but with the addition of further treatment upgrades, including converting the plants operation to an activated sludge system,” the statement read.
Bill Taylor of the Friends of the Molalla River said the activated sludge pump would help deal with the Biological Oxygen Demand (BOD) problems of discharging into Bear Creek.
The cost of the intake and pump station would be $3.8 million, plant improvements would be $10 million for a total $13.8 million. Without considering additional O&M, this option would rate payers bills by $36.43 per month.
• The final option the city presented was storage at low flows in Bear Creek.
“This option assumes the DEQ would allow continued discharge to Bear Creek, at a similar dilution factor as in the current permit,” the statement read. “During low flow periods in Bear Creek treated effluent would be stored in a new lagoon. During high stream flow periods, water would be taken from the new pond, and discharged into Bear Creek along with effluent from the plant.”
The cost for plant improvements would be $2.1 million, storage lagoons would be $12.2 million for a total cost of $14.2 million. Without considering additional O&M, this option would increase costs to the rate payers by $37.48 per month.
As to other options that FMR has looked at other than wetlands, FMR spokesperson Mark Schmidt said there was no tangible plan.
“It’s not that we haven’t (discussed options outside of wetlands),” he said. “We have talked about other alternatives and compromise points and what is reasonable, but as far as developing anything beyond that pipe dream, we haven’t. ... Not being a wastewater engineer, I think we’re at the point that we need to gather a blueprint of the plant and sit down with people who are able to be real about it, and that means dollars, and I don’t think the Friends of the Molalla River has the budget to buy the engineering for the city of Molalla at this time.”
For Sage, looking at alternatives is really a matter of dollars and sense.
“It is up to the city on how much money they want to spend to get the same results (as the current plant),” he said. |
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