By Dan Gunderson, Minnesota Public Radio News, Published November 09 2009
Failing sewage plant endangers Lake of the Woods
The treatment plant is only nine years old. Replacing it will cost
$1.6 million, and city officials say they can’t afford to fix the problem.
About 200 people live in Williams, just a few miles from Lake of the Woods. There’s a gas station, bar, post office and a sewage treatment plant that was built in 2000.
The plant was designed to last a minimum of 40 years, but the tank that holds the raw sewage is heavily corroded and starting to leak. According to engineers, a major leak could happen any day.
“You can see where it’s starting to come through,” said Leonard Cole as a he examined discolored spots on the tank where moisture is seeping through the corroded metal.
Cole operates the sewage treatment plant. In fact, he is the Williams Public Works Department.
“It works good, It’s just going to heck,” said Cole as he pointed out corroded areas.
That’s a big problem for Williams.
Mayor Nancy Jewell said the sewage plant construction was funded by federal loans and the city has 31 years of loan payments left on a sewage treatment plant that needs to be replaced.
“No one wants to admit responsibility for it. So it’s like we’re stuck between a rock and a hard place,” Jewell said. “We’re responsible for it and we just don’t know what to do. We’ve been pulling our hair out trying to find a way to solve the problem and no one wants to help us.”
The aluminum tank is 60 feet long, 20 feet wide and 12 feet deep. Engineers found the one-fourth inch thick aluminum walls are now less than one-eighth of an inch thick because of corrosion.
The city contends faulty material is to blame. The engineering firm that designed the plant thinks chemicals the city added to the treatment contributed to the corrosion.
The Minneapolis firm that designed the plant 10 years ago said it recommended a steel tank with corrosion coating, but the manufacturer persuaded the city to use aluminum.
The city recently hired a consulting engineer who thinks the corroded tank could last two years, but is more likely to fail much sooner.
One option is coating the inside of the tank to stop the corrosion, but engineers think the corrosion might be too advanced and the tank too weakened to repair. Replacing the treatment plant will cost about $1.6 million.
Consulting Engineer Tim Korby is concerned that if the tank fails, some 50,000 gallons of raw sewage a day will flow into a nearby creek which flows into Lake of the Woods.
“We’re telling the state it is going to fail,” Korby said. “Are we going to do something now or wait until it fails and contaminates Lake of the Woods? There’s ample funds in the state and the feds to do projects like this. It’s a matter of everyone coming together and saying this is a priority. We want to protect Lake of the Woods the water and the fisheries there.”
It’s unclear how a sewage spill would affect Lake of the Woods. Neither the city nor the Minnesota Pollution Control Agency has done an analysis of what would happen in the event of a large sewage discharge.
The MPCA approved the plans for the Williams sewage treatment plant, but their only role is to examine whether the plant satisfies wastewater treatment requirements. According to agency officials, it does not tell engineering firms how to build treatment plants or what materials to use.
MPCA Clean Water Revolving Fund Coordinator Bill Dunn said the agency has engineers examining the problem.
“I think we share the concern that this is a very serious issue that needs to be resolved in a timely basis,” Dunn said. “It may be wise to also take a longer term perspective to determine whether this type of facility is really the best fit for the community in the long run.”
The state Department of Employment and Economic Development has emergency funds for small cities, but Dunn said it’s not clear if Williams meets the criteria to qualify for those funds. He said the project ranks low on the MPCA statewide priority list for funding in part because it’s a relatively new facility.