ELIZABETHTOWN - Data from an ongoing study indicates that water quality in both branches of the AuSable River steadily declines as it moves downstream and passes through places of human habitation.
According to AuSable River Association Executive Director Dr. Carol Treadwell, both the east and west branches of the AuSable River begin as relatively uncontaminated streams, but become continually more concentrated with dissolved solids as the water moves downstream.
"Some source, human or natural, is contributing a large content of ions," Treadwell said. "We don't know what they are, but we will be spending next summer finding that out."
Initiated in 2009, the Au Sable River Association water quality study measures the amount of particulate and dissolved pollution by measuring the water's electrical conductivity.
Treadwell suspects much of the contamination originates from human activity and points to factors like road salt, water runoff and clearing vegetation along riverbanks as a few possible reasons for increased contamination levels.
"It seems like there may be a large contribution from the roads," Treadwell said.
A recently completed study by Paul Smith's College and ADK Action concluded that road salt has substantially raised the sodium levels of numerous Adirondack water bodies.
The research found especially high levels of contaminates near state Route 73 in Jay and the Keeseville Wastewater Treatment Plant.
Treadwell said that increased particulate and dissolved contamination could devastate trout spawning grounds and decimate the fish population.
In 2003 the state Department of Environmental Conservation estimated that fishing tourism on the Au Sable alone has a $3.8 million economic impact on the region.
Officials estimate the current regional economic impact of the fly fishing industry could be in excess of $5 million annually.
Currently, five businesses that specialize in providing gear and guiding service along the Au Sable employ as many as 51 area residents during the fly fishing season.
Treadwell suggests that municipalities begin spring road cleaning earlier than usual at sites close to the river. She also said vegetative replanting along the river's banks could stem much of the erosion that is dumping tons of particulates into the Au Sable each year.
Essex County Department of Soil and Water Director David Reckahn said each year the county and hundreds of residents plant between 5,000 and 10,000 trees, many of them along the banks of the Au Sable.
Treadwell and her research team will spend the 2010 summer season trying to pin down the exact sources of the contaminants.