HADLEY — The dam whose construction created the Great Sacandaga Lake in 1930 is slated for a major rehabilitation project.
The state announced Tuesday that it will seek proposals for engineering and oversight for work that would start in late 2023 at the earliest. The current state budget allocated $20 million for the project and more will be appropriated if needed, Gov. Kathy Hochul said in a news release.
The hope is that no unusual drawdown of the lake’s water level will be necessary to complete the overhaul, but that is to be determined by the extent of work identified as necessary in the engineering assessment.
The 95-foot tall Conklingville Dam across the Sacandaga River creates a 42-square mile lake containing up to 37.7 billion gallons of water drained from roughly 1,000 square miles of the southern Adirondacks. It is operated by the Hudson River-Black River Regulating District.
District Executive Director John Callaghan said Wednesday that the dam is solid and up to modern standards but it is showing its age.
Some structures built to the standards of their era, even if they don’t deteriorate, become inadequate or obsolete with the passage of time as standards update. But nearly a century later, the Conklingville Dam isn’t one of them.
“Here we have a dam that holds up very well even when viewed in light of modern dam safety,” Callaghan said. So this is not a redesign project, but a maintenance project.
Improvements to be made include:
- Foundation and concrete structural repairs to minimize and eliminate leakage through the rock base and at the rock-concrete joints;
- Replacement of deteriorated concrete on all concrete surfaces;
- Replacement and repair of spalling and damaged concrete along wing wall, outlet channel, and tailrace structures; and
- Replacement of original low-level Dow valve outlets with modern outlet valves.
The Great Sacandaga Lake is a recreation destination and regional resource, and the Hudson River-Black River District hopes to avoid drawing down water levels in the lake so that repairs can be made.
“Our hope and even our tentative plan is to do the work without any disruption or change to normal operating protocols,” Callaghan said.
That could change if the assessment reveals more or different work than expected needs to be done, he said.
This will be the first comprehensive overhaul of the dam in its lifetime, he added. Previous work has been limited to specific components, and some concrete work was done in the 1980s and 1990s.
The Great Flood of 1913, which inundated riverfront communities in Albany and Rensselaer counties and sparked a typhus epidemic in its wake, led directly to the construction of the dam and the Great Sacandaga Lake as a flood control measure.
When heavy rain or snowmelt causes the Sacandaga River to swell, the dam can keep much of that water from entering the Hudson River and threatening downstream communities.
In a news release, Hochul juxtaposed the floods of a century ago against the modern-day series of severe weather events that are causing havoc of their own:
“We are seeing the reality of climate change here in New York and across the country year after year, and it is no longer acceptable to simply hope for the best while failing to make the necessary investments in public safety and resiliency,” she said. “We need to make smart, strategic investments in critical infrastructure like the Conklingville Dam and other flood protection infrastructure without delay as part of a comprehensive strategy to protect our communities and New Yorkers.”
The Great Sacandaga Lake typically fills with snowmelt runoff in spring and is gradually drained down the rest of the year so there’s room to contain the next year’s snowmelt.
“This summer the Great Sacandaga is a bit of a yo-yo,” Callaghan said, particularly after the heavy rains of July.
“That is a storage reservoir doing its job. It takes the peaks and the valleys out of the downstream flow.”
Reach John Cropley at [email protected], 518-395-3104 or @cropjohn on Twitter.