While trucks were spreading less salt per mile, trip frequency increased, monitors say
By Zachary Matson
A state project to test ways to reduce road salt use may be resulting in more of the environmental pollutant flowing into Lake George.
The state Department of Transportation during a years-long salt reduction study on Route 9N along Lake George actually increased the overall salt load entering the prized lake, according to a multi-year monitoring project by the Lake George waterkeeper.
While state highway crews cut the amount of salt dropped per lane mile, they made more frequent trips and thereby increased the overall amount of salt spread in the Lake George basin, Waterkeeper Chris Navitsky and researchers Jim Sutherland and Brea Arvidson found during a five-year study.
“Each time the truck went out, they were putting down less salt; however, from their own records, they were going out two to three times as often,” Navitsky said in a recent interview. “That offset any reduction from the rates.”
Navitsky and Sutherland initially hoped to partner with DOT to assess the agency’s pilot project but that collaboration fell apart in 2018, a few months after the state agency announced plans for the Lake George pilot project and one in the Lake Placid region.
The waterkeeper report comes as DOT prepares to expand pilot projects to more corners of the Adirondacks with an aim of reducing salt use. In its report, the Adirondack Road Salt Reduction Task Force leaned heavily on the use of pilot projects to test reduction strategies that could be implemented throughout the Adirondack Park.
Rob Fitch, DOT’s director of transportation maintenance, at a road salt summit earlier this month said he expected the agency to have details about the forthcoming pilot projects by Dec. 1.
The task force report proposed expanding existing DOT pilot projects and establishing new ones to test salt reduction strategies and model how to expand those practices widely.
When state officials established the Lake George pilot in 2018, they outlined plans to use new plow blades, brine roads, measure salt application and reduce salt use by 10% along a 17-mile stretch of Route 9N north of the village of Lake George.
The Lake George researchers estimated that during the past five winters DOT exceeded the 10% reduction in its application rate and appeared to apply the reductions throughout the lake basin, not just the Route 9N segment. Those reductions, as high as 20%, though, were offset by an increase in trips.
In a statement, DOT spokesperson Glenn Blain said the waterkeeper report demonstrated DOT had “significantly reduced salt application rates on highways throughout the Lake George Basin” and blamed the increased number of salting trips on weather.
“The number of application events is dependent on weather conditions as NYSDOT must always fulfill its obligation to provide reasonably safe conditions for motorists,” Blain said.
Blain did not respond to questions about how the agency has evaluated the Lake George project, whether it could provide documentation of its own review or how it planned to assess the new pilot projects.
The final requirement under the law establishing the road salt task force mandates DOT provide a report of the pilot projects to lawmakers by August.
Countering DOT’s contentions, Navitsky said precipitation and snowpack records did not align with a trend of increasing winter severity, at least in terms of snowpack. He added that a recommendation from their study was that DOT should more consistently track storm conditions and winter weather. The number of salting trips increased significantly in the third year of the project and stayed elevated in the fourth and fifth years.
“Our feeling is they just went out more often,” Navitsky said.
In 2014, a State of the Lake report summarized three decades of Lake George water chemistry and rated salt levels as one of the biggest threats to the lake, along with invasive species and declining water clarity. That report showed that sodium-chloride concentrations in Lake George nearly tripled between 1980 and 2009, threatening to alter the fragile balance of phytoplankton in the lake and the lake’s circulation patterns.
The 2014 report spurred efforts around the lake to reduce salt use among municipal highway departments, but advocates realized the state was a key driver of salt pollution. Efforts to include DOT culminated in the Route 9N pilot.
State officials initially discussed a monitoring collaboration with non-government researchers but walked away from those plans as the risk of lawsuits over contaminated drinking wells grew in the wake of an Adirondack Watershed Institute study, Navitsky said. The AWI study found that numerous residential wells had been contaminated by road salt runoff from state highways.
The lack of collaboration ultimately delayed the waterkeeper study. As the potential collaboration fell through, DOT staff informed the researchers that agency lawyers advised them to not provide salting data outside the state Freedom of Information Law process.
When the researchers filed document requests, it took the agency 15 months to deliver the data they sought – and at first provided data for the wrong part of the state and in inconsistent formats.
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“We would have had a lot of these answers a lot sooner, if they had been more forthcoming with the data that we requested. So again, not really a cooperative effort,” Sutherland said. “They have just done it the way they want to. That’s DOT: do it the way you want to, because they don’t listen to anybody else.”
To evaluate the DOT pilot, Navitsky and Sutherland studied chloride concentrations and water flows in four tributaries, two within the pilot road segment and two outside of it. In each tributary, they measured chloride levels above and below the state managed road, picking test sites to eliminate other potential sources of salt.
They used DOT’s own data to determine how much salt was used on Lake George and how many trips state highway crews made.
The report also highlighted the existing reservoir of chloride embedded in soil and groundwater after decades of salt use seeping slowly into the Lake George’s tributaries and deep basin. The researchers at two sites calculated much more chloride entering the lake than was put down as road salt that year, a sign of chloride stored in the environment from previous winters gradually migrating to the lake, especially in the southern part of the lake basin.
If state officials hope to learn from the pilot projects outlined by the task force, they should already be collecting baseline data ahead of the new winter season, Navitsky and Sutherland said.
They said DOT should work with local researchers and detail monitoring plans. Instead, they said they don’t know how the agency plans to evaluate the projects.
“I question whether they will be able to provide the data in August in order to develop a definitive report to detail and evaluate their pilot programs,” Navitsky said.
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