By JEFF MEYERS
PLATTSBURGH — Efforts to reduce the amount of phosphorus entering Lake Champlain have not been tremendously successful, but researchers continue to stress the need for ongoing reduction efforts.
Researchers from New York, Vermont and Quebec recently released a technical report looking at phosphorus loading in the Lake Champlain basin between 1990 and 2008. Data from that report shows the region has a long way to go to meet targeted phosphorus levels.
NO SIMPLE ANSWER
"One of the issues we wanted to address is what's the status of phosphorus in relation to our water-quality goals and targets," said Eric Smeltzer of the Vermont Department of Environmental Conservation and lead writer for the report.
"It's hard to give a simple answer to that because the lake is so diverse," he added. "Some areas are meeting targets in the lake; others are not. Most areas have more phosphorus than they should."
Phosphorus is a nutrient that promotes aquatic plant growth, including such unwanted species as blue-green algae. Phosphorus levels vary in regions of the lake based on a variety of factors, such as water depth, currents and sources.
WHERE IT ORIGINATES
"There are two basic sources for phosphorus loading," Smeltzer noted. "There is wastewater discharge, and then everything else is lumped into 'non-point' sources, including agricultural runoff, storm drainage and river stabilization.
"We're adding more phosphorus than we should be, and it's overwhelmingly from non-point sources," he added.
"This is not really new, but when confirmed in the report, it's become even more true."
Basin-wide, the lake's nearly 100 wastewater-treatment plants produce merely 5 percent of the overall phosphorus entering the lake.
In the 1970s, those plants contributed to nearly half of the phosphorus loading, but improved treatment techniques and laws prohibiting phosphorus in laundry detergent have helped correct that problem.
"We have (phosphorus) targets established for wastewater facilities," Smeltzer said. "Every facility in the basin has its own individual limit on tons per year they can put in, and nearly all are meeting their targets.
"The priority clearly belongs to non-point reduction efforts."
OTHER CONTRIBUTORS
Both Vermont and New York have been initiating efforts to reduce non-point-source pollution, including improved agricultural practices and upgraded drainage systems along roadways.
"One thing positive we've found in the report is that inputs are not generally getting larger despite ongoing growth," Smeltzer said. "At least we've been able to compensate for that growth, but we need to do more to hold the line."
One of the challenges researchers face is the fact that the lake does not respond rapidly to changes. Improvements to water quality are not immediately recognized, stretching the patience of a society that often looks for the quick fix.
"What we need are other methods to measure success," Smeltzer said, adding that researchers need to identify increases in the kinds of programs that will eventually lead to success.
The report also looks at trends in phosphorus loading and at levels in the lake's tributaries.
E-mail Jeff Meyers at: jmeyers@pressrepublican.com
