City of Fitchburg public works staff are recommending the city relieve Lake Barney flooding by moving water toward the Village of Oregon through a drainage ditch leading to Cusick Parkway.
At a Wednesday, March 24, Committee of the Whole meeting, city environmental engineer Claudia Guy and Emmons and Olivier Resources, Inc. water resources engineer Nicholas Hayden presented the Common Council three options for lowering the lake, all of which had the same core principles but lowered the lake to different levels based on how much water is moved out of the area.
The options presented to the council included lowering the lake to 942’ above sea level, which is the lake’s natural height; lowering it to 944’ and then 945’. Because the area around the lake is fairly flat, much of the cost would involve creating a drainage ditch across the state Department of Corrections and Alpine Dairy properties.
Guy recommended the city adopt the 944’ plan as a way to balance impact with cost, which includes construction of the project, an estimate for wetland management and maintenance.
The 945’ option would cost the city and its agency partners the least at $880,000, but provide the least amount of benefit to the surrounding properties. with between $2,000-$7,000 in annual benefit to each city resident with 50 acres of land being reliably farmable. The annual benefit comes in the form of the ability to harvest crops and rent out farmland.
The 944’ plan would cost $1,044,000, in return for a maximum of $12,500 benefit and 59 acres of farmland being usable; and the 942’ plan, the most expensive at $1,436,000, would give a maximum of $28,000 in annual benefit, with 71 acres of land being reliably farmable.
“(It) appears to strike the best balance between project cost, benefit, effectiveness and ability to be approved by permitting agencies,” Guy said.
Lake Barney, which sits near the top of the Badfish Creek Watershed, has grown from a 42-acre body 33 years ago at an elevation of 942’ above sea level, to around 800 acres and 949’ feet above sea level during times of heavy rains. The lake stopped naturally overflowing in July 2020, nearly two years after heavy precipitation first caused it to drastically expand.
The increase in lake capacity has continued to cause problems for Fitchburg and Oregon residents. In addition to the individual costs to keep the water at bay that involve filling in basements and keeping permanent flood barriers up to keep water away from a home, the glacial kettle has also put pressure on the water table, causing fields to flood and drowning out the roots of trees that predate the Revolutionary War.
And after years of flooding, figuring out how to drain the water safely without disrupting the areas downstream continues to be complicated because of who owns what land surrounding it, and where.
The affected areas include jurisdictions of Fitchburg and the town and village of Oregon, as well as protected federal Fish and Wildlife land managed by the state Department of Natural Resources and farmland owned by the state Department of Corrections.
Flooding in the area has caused Village of Oregon’s Rotary bike trail to be submerged, and Netherwood Road to close down multiple times in the last two-and-a-half years, causing water issues for people living around Lerner Park.
Hayden told alders that if the city chose to do nothing with lowering Lake Barney, it would take between 5-10 years for water to infiltrate out of the area under normal climate conditions, but could take longer if recent patterns of high precipitation continue.
“This long timeline for the drawdown is due mostly to the slow nature of groundwater movement,” he said. “Until the water table drops across the area, the lake will continue to drain slowly and will be susceptible to being filled back up again during heavy rain events.”
Without an outlet, the area would also see approximately $185,000 of permanently lost agricultural land devaluation, and a $114,000 cost-to-cure for resident Tom Thayer, who has the permanent flood barriers around his home. At the 942’ option, land devaluation and cost-to-cure for Thayer’s property would be just over $100,000 combined, Hayden said.
Installing an outlet for Lake Barney would cause the lake level to fall rapidly, Hayden said, but surrounding water table levels would fall relatively slowly because soil in the aquifer isn’t quick to release water. With both an outlet and a drainage ditch, Lake Barney could drain in anywhere from 49 to 87 days.
The council will have the final say on which option the city goes with, or if it will do the project at all. The project wouldn’t happen until at least 2023, as the city needs to wait for the Village of Oregon to upgrade its stormwater management infrastructure downstream to ensure that it can handle the water draining from Lake Barney to the north into the rest of the Badfish Creek watershed. The village isn’t planning on starting that project until 2022.