Editor’s note: This article is by Matt Mientka, of the Stowe Reporter, in which it was first published Nov. 13, 2014.
Recreation is gaining the upper hand on flood control at the Waterbury Dam.
This summer, more than 42,000 people used the dam’s 850-acre reservoir for recreation — swimming, boating and picnicking.
In deciding the reservoir’s future, state officials have decided that the summertime water level should be maintained year-round — which would eliminate the longtime practice of draining the reservoir before winter, to make room for spring runoff from Mount Mansfield and the rest of the dam’s expansive watershed.
Many residents are concerned about another flood soon on the heels of devastation caused by Tropical Storm Irene in 2011.
“Hasn’t Waterbury suffered enough?” one commenter opined on VTDigger.org.
The state says the summertime water level, which balances competing environmental, safety and recreational interests, is safe for the town.
The Vermont Department of Environmental Conservation recommended last week that the state stop draining the reservoir every winter, keeping the water level at an average of 589 feet above sea level. Now, the reservoir is drained every winter to between 540 to 560 feet, and then replenished gradually through spring.
By maintaining a consistent water level, the state hopes to protect fish and prevent soil erosion, while continuing to provide flood control.
At the same time, officials want to provide the recreational opportunities that thousands of residents and tourists enjoy every summer.
With the change, water flow through the dam would more closely match the natural flow of the Little River, David Mears, commissioner of the Department of Environmental Conservation, said last week.
The debate about the reservoir was prompted by Green Mountain Power’s application to renew its operating license for a hydroelectric system.
“Waterbury Reservoir and the Little River are widely used and loved by many thousands of Vermonters,” Mears said in a statement. “We have worked hard to develop a water quality certification that meets our obligations to protect water quality, continues to allow Green Mountain Power to generate clean, renewable energy, and ensures that the dam will continue to provide downstream communities with critical protection against flood damage.”
The hydroelectric dam generates an average of 15 million kilowatt-hours per year.
The new plan would reduce water fluctuations that help hydropower production but harm fish and other organisms downstream of the dam. But first, gates and spillways at the dam need to be replaced, a $40 million project. The state will pay about $15 million of that.
Mears said the state will seek an agreement with the U.S. Army Corps of Engineers to assess dam safety when the gates and spillway are replaced.
Water management at the dam would not change until engineers confirmed that the new gates and spillways can be operated safely.
Jeff Crocker, an environmental analyst at the environmental agency, told the Waterbury Record that the state has a plan to manage springtime flooding, which would be manageable even with the reservoir at a higher year-round water level.
“The state will be working with the Army Corps of Engineers during the design of the gates and spillways,” he said. “And at that time, the Corps will also be doing a dam safety assessment to address concerns about managing safety and the possible impact of flooding.”
To control flooding during springtime snowmelt and large storms such as Irene, engineers are considering criteria to draw down water elsewhere besides the reservoir.
The state plans to finalize project details by the end of the year, with construction to be completed within five years. The department will host a public meeting on Saturday, Dec. 6, at 1 p.m. at Crossett Brook Middle School in Duxbury, and will accept written until 4:30 p.m. that day.
The U.S. Army Corps of Engineers built the dam over a three-year period to control springtime floods after a Winooski River disaster killed 55 people in 1927.
