Marcy Dam, an iconic spot for many Adirondack High Peaks hikers, will be removed because of damage done by Tropical Storm Irene, the state Department of Environmental Conservation has decided.
The small dam on Marcy Brook is familiar to thousands of hikers who pass it on their way to Mt. Marcy, Mt. Colden and other popular climbs. There are popular campsites nearby.
The dam, a wooden structure located between concrete abutments, sustained significant damage during the 2011 tropical storm and no longer meets DEC dam safety regulations.
The removal would be done incrementally over five years to minimize the amount of sediment going downstream.
Prior to Irene, a popular hiking trail from the Adirondack Loj into the High Peaks crossed a footbridge on the dam, which held back Marcy Pond. High waters during the storm took out the top of the dam, including the bridge. That caused the pond to drain, leaving mud flats.
DEC spokesman David Winchell said any repairs would have to bring it up to modern standards, at “prohibitive” cost.
The dam has no practical or environmental benefit at this point, he said, and prevents fish from moving upstream.
The state considered just letting the dam deteriorate over time, but decided the risk of a failure that would send damaging amounts of sediment downstream was too great.
“It must be recognized that important principles of wilderness management include allowing rivers and streams to flow unfettered and to minimize human-made structures,” Winchell said.
The pond view, which often reflected the surrounding mountains, was aesthetically pleasing enough that some hikers writing on Adirondack online forums have called for the dam’s replacement.
But Neil Woodworth, executive director of the Adirondack Mountain Club, said removing the dam makes sense.
A replacement would have to comply with new safety standards established after the failure of the Hadlock Pond dam in Washington County in 2005, he noted.
“When DEC replaces a dam, the standards are just so much greater, and hence the cost greater, than they were even 10 years ago,” Woodworth said. “With the amount of money the state has, replacing Marcy Dam doesn’t make sense.”
After Irene, a new footbridge across Marcy Brook was established about 200 feet downstream of the dam. But until now, the dam’s fate was uncertain.
The first phase of dam removal would be to remove two logs on the dam, allowing for a slow release of sediment that has built up behind it.
The dam would ultimately be lowered approximately 15 feet below the spillway crest, returning Marcy Brook to its original stream grade.
Doing the work over a five-year period will allow vegetation to grow on exposed shoreline each year and minimize the amount of sediment that spreads downstream. Marcy Brook eventually flows into the Ausable River, a trout stream.
The dam is about a two-mile hike from the Adirondack Loj, which is about eight miles south of Lake Placid.
Another back-country dam, at Duck Hole on the Cold River, was swept away and is not being replaced despite the wishes of some hikers.
Elsewhere, many High Peaks trails were damaged during the storm. Many of them have since been rerouted.
A water quality permit for the work is under review. Public comments on the Marcy Dam removal plan will be taken through Jan. 23.
Those wishing to comment may contact Erin M. Donhauser, DEC Region 5 headquarters, 1115 Route 86, Ray Brook, NY 12977 or email firstname.lastname@example.org.