As winter settles into the Adirondack High Peaks, few things are as reliable as the steady crunch of road salt underfoot. But in Lake Placid, that familiar winter staple has become a growing environmental concern. Mirror Lake — the village’s centerpiece, both scenic and symbolic — is showing clear signs of stress from decades of heavy salt use, raising questions about how communities can balance safety with sustainability.
Students in Ms. Fagan’s Adirondack Science class shovel pathways to reduce road salt usage on campus. Photo provided.
Each winter, local and state highway crews apply thousands of tons of sodium chloride to roads and sidewalks to combat icy conditions. When temperatures rise or snow melts, that salt washes into nearby streams and storm drains, funneling directly into Mirror Lake. Because the lake sits at the bottom of a steep, developed watershed, it is one of the most salt-vulnerable bodies of water in the Adirondack Park.
Scientists and local nonprofits, including the Ausable River Association, have been tracking the lake’s chemistry for years. Their findings show a steady rise in chloride levels — now high enough to disrupt the lake’s natural mixing. Mirror Lake typically turns over twice a year, in spring and fall, a process that circulates oxygen to deeper waters. Elevated salt concentrations can prevent turnover. In fact, researchers documented a complete mixing failure in several recent years, meaning deep waters went without oxygen for extended periods.
This lack of oxygen has real ecological consequences. Fish species such as lake trout, which rely on cold, oxygen-rich water, face increasing stress. Aquatic insects, plants, and microorganisms that help maintain water quality are also affected. The lake’s overall resilience weakens as its chemical balance drifts further from natural conditions.
Yet the issue is not simply scientific — it’s deeply intertwined with the village’s identity. Mirror Lake is a hub for recreation, from Ironman training swims to summer paddling and winter dog sled rides. Its shoreline anchors Lake Placid’s tourism economy. As chloride levels climb, residents worry about long-term impacts on both the environment and the local lifestyle.
What are we doing to help Northwood?
Our very own Adirondack Science class, taught by Ms. Marcy Fagan, has been helping the maintenance crew shovel before the snow turns to ice. This is very important for reducing salt use at Northwood. Last winter, we achieved a 75% reduction in salt use with this new shoveling team.
Efforts to address the problem are already underway. The Village of Lake Placid and the Town of North Elba have begun reducing salt use by calibrating equipment, improving plow efficiency, and experimenting with brine mixtures that use far less sodium chloride. Some sidewalks in the business district now use alternative traction materials instead of traditional rock salt. Public education campaigns also encourage homeowners and businesses to limit their salt use.
While progress has been noticeable, experts emphasize that recovery will be slow. Chloride can remain in the water and surrounding soils for years. Still, many see Lake Placid as a potential model for how northern communities can rethink winter maintenance while protecting freshwater resources.
For now, Mirror Lake remains clear, beautiful, and central to village life, but its future depends on choices being made each winter. As one local scientist put it, “What happens on our roads doesn’t stay on our roads. It ends up in our water.”
