The Village of Essex Junction has experienced three large accidential discharges from the municipal water treatment facility in the last three months.
Two of the releases totaled between 500,000 and 1 million gallons, but water quality superintendent Jim Jutras said all of the recent releases have been near the end of the treatment process and were not raw sewage.
The recent problems at the facility all center around the chlorination and dechlorination of wastewater, which must be completed before it is released into the Winooski River.
Jutras said the problems have sometimes been related to ongoing upgrades at the treatment center.
“They’re all centering around this one area that’s under heavy construction right now,” Jutras said.
The construction is part of a system overhaul at the treatment facility that Jutras said will introduce more “checks and balances” to prevent overflows and accidental spills.
The difficulty right now, Jutras said, is that the facility has to keep operating and treating wastewater as the upgrades are installed.
“We’re doing everything we can to stay on top of it,” he said on Thursday. “We have automated systems that are partially installed, and hopefully the control guy will show up tomorrow and take us to the next level.”
Upgrades to the system are about 80 percent complete, Jutras said, and all construction near where raw sewage is processed was completed without any accidental releases.
“It’s been the disinfection system,” Jutras said. “That’s been our challenge.”
Ross Saxton, the director of conservation and education at the advocacy group Lake Champlain International, said sewage releases are a big problem in Vermont.
“If you look around the state,” he said, “all of these treatment facilities are out of date.”
While Essex Junction is upgrading its system, most municipalities haven’t dedicated funds to do the same.
“When it comes down to it, it’s the select board of each town who is responsible for ensuring that these treatment facilities … are working properly,” Saxton said.
Even though a large release doesn’t seem to have an immediate impact, Saxton said, “the overflows accumulate, so a million gallons here … 50,000 there … that all adds up, and those overflows contain nutrients like phosphorus that otherwise would have been filtered out and mitigated.”
Some of these “nutrients” can be helpful, but others can lead to big problems downstream such as blue-green algae blooms and killed aquatic life.
The scale of the problem in Vermont, Ross said, is growing as wastewater facilities age, but most towns either don’t recognize or prioritize the issue.
“I think what it comes down to is getting people on the same page where they understand the urgency of the situation,” Ross said.