Heber Valley Special Services Board seeks sewage odor solutions
An environmental consultant said injecting a "very small amount" of hydrogen peroxide into the system may offer relief.
Heber City Mayor Heidi Franco said her city will do its part to mitigate the smell from the sewage treatment ponds near Midway by adding a probiotic solution to wastewater coming from Heber.
While Heber City residents haven't complained of odor issues, "we should be proactive," she said at Heber Valley Special Service District's board meeting Thursday.
Clair Provost, vice-chair of the Midway Sanitation District, announced the city will be testing for hydrogen sulfide at over 160 manhole covers within Midway’s "area of concern." Provost said the district hopes to have that data within a week.
Wes Johnson, an engineer with the district, added that the sewer lines along Michie Lane — the road in Midway just north of the facility — will be cleaned out soon, a year ahead of schedule.
"After we've done the H₂S, testing, we'll then clean the line summer of ‘23 and then retest, and see if cleaning the line more often has an impact," he said.
The Special Services District has also contracted with Michigan-based Environmental Resources Group to analyze water samples from the ponds themselves and recommend emergency solutions.
Mala Hettiarachchi, a senior engineer with the group, told the board the problem was likely the result of temperature stratification in the ponds, which erodes when the seasons change.
"Before we can recommend a sustainable solution for these odor issues, we need to evaluate the current conditions of the lagoons to actually better understand the nature of the stratification," she said.
Hettiarachchi said hydrogen sulfide was the likely culprit for the smell. She said injecting small amounts of hydrogen peroxide into the system would be the most likely short-term solution, which has proven effective in similar situations elsewhere.
Hettiarachchi said the group would need about a week to analyze the samples once received, and then provide recommendations.
The board also discussed more long-term improvements in the works, which include the planned installation of another aeration basin at the facility’s physical treatment plant. (The plant handles about 20% of the Valley’s wastewater, while the ponds treat the other 80%.)
Brad Rasmussen, principal engineer at Aqua Engineering, told KPCW the aeration system will be installed to accommodate expected future growth in Heber Valley. He said it also presents an opportunity to get sludge out from one of the ponds that’s been accumulating for 40 years.
He said wastewater could temporarily be diverted away from the pond, which would then dry out and leave the sludge behind. The sludge would then be removed by tractors.
"The other option is go in with a dredger that basically is a float with an auger on the front and pumps it out as liquid," he said. "But when you do that, it's going to stir it all up, so it's going to make odors. So it's kind of pick your poison."
The board did not make a final decision on which method it would pursue.
In stark contrast to the previous board meeting, only a few residents came to this one. But they expressed dismay when the board addressed one of the final items on the agenda, the formation of a citizen advisory panel to work with the board on solutions.
The version brought before a vote would have a board chair which would be a member of the services board, three technical experts, and one neighborhood representative. Just before the board voted to approve, Midway resident Jordan Councill voiced his objection, preferring a panel of five citizens.
"The idea is that you're the voice people, not to pack it full of special witnesses and technical people," he said. "It's to be a citizen's voice."
Such a panel seemed more like "grievance panel" instead of one oriented towards solutions, Midway City Mayor Celeste Johnson countered. Having one citizen act as a liaison between the board and residents was more effective, she said.
"And then folks can submit questions and say, 'My 50 hours of Google searching has really shown this.' And then we can have some technical people that can really speak to that," she said. "I think that that's a realistic way to get stuff done."
The board approved the original plan with one tweak — the panel would have two citizens, with one serving as an alternate.