America’s dams are showing their age. The American Society of Civil Engineers has graded the nation’s more than 92,000 dams at D-plus, with nearly 17,000 considered high-hazard potential because failure threatens lives and property.
That backdrop set the stage for a major safety-focused overhaul at Indian Lake Dam in upstate New York. The 550-foot-wide, 47-foot-tall structure, built in 1898 and managed by the Hudson River-Black River Regulating District, combines a concrete masonry dam with an earthen embankment that helps regulate flows and reduce flooding risk in the Upper Hudson River Watershed.
Colliers Engineering and Design began a detailed assessment in 2018 that included records review, field surveys, subsurface borings, breach and stability analyses, and a hydraulic evaluation. The team also examined the dam’s mass concrete core, stone masonry exterior, and access walkway.
Core sampling showed serious deterioration in the concrete portion of the dam, contributing to leakage. The project team performed leakage improvements and installed a retaining wall to strengthen the dam. Work at the gatehouse also required divers placing concrete under about 30 feet of water during Adirondack winter conditions.
Several scope items tie directly to masonry craft and repair decisions that matter on complex infrastructure jobs. The project included repointing masonry both above and below the water level, plus sluice gate modifications that replaced original wooden elements. To boost hydraulic capacity and safety, the team also added an auxiliary spillway.
Engineers targeted three headline issues. Spillway capacity increased with improvements that included raising the crest of the earth portion of the dam. Structural stability improved with anchors built into bedrock. The embankment slope was flattened to improve stability.
The $18.3 million project finished this year, offering a clear reminder for owners and contractors alike that long-standing masonry and concrete structures demand proactive condition assessment, disciplined repair execution, and tight coordination across design and construction teams.
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