Collaborative LGA Project Redirects, Diffuses Dangers Of Polluted Stormwater

September 18, 2020

This announcement was published prior to the merger of the LGA with The FUND for Lake George in June 2021.

Direct, actual protection of Lake George’s water quality means many different things, including creating new ponds to capture and clean polluted stormwater.

All done with the approval and assistance of New York State.

On a small, steep spit of land between the Northway, the Exit 22 southbound offramp, and the bridge leading to Route 9, LGA Project Manager Randy Rath set about on a project to protect the Lake’s water quality, continuing to smartly use a grant from the Lake Champlain Basin Program dedicated to innovative work.

Randy worked with New York State Department of Transportation crews and staff from Warren County Soil and Water Conservation District to create a “diffuser pond” that dramatically reduces the volume of polluted stormwater getting into the Lake and lowers the impact that nutrients in the polluted stormwater could have on the Lake.

Exit 22 Work Locator Map

“We know that polluted stormwater is the biggest concern for water quality decline,” said Randy. “Polluted stormwater carries phosphorus, nitrogen, salt, soil and many other things that hurt the Lake.”

“The LGA works to stop it everywhere we can, every way we can, to prevent a decline in the water quality and lower the appearance of algae, and potential of a HAB,” Randy said. “Everyone who loves the Lake should work to stop polluted stormwater.”

Lake George has never had a Harmful Algal Bloom (HAB), and the LGA’s goal is to ensure the conditions are never right for one to form. The most important insurance: Stop nutrient-rich polluted stormwater before it gets into the Lake.

The diffuser pond at Northway Exit 22, under construction in the photo at right, expanded on work performed and ideas implemented in 2019 by the LGA, DOT and Soil and Water. When it rains in that area of the Lake George watershed, the stormwater flows from many directions, including the rest area parking lot, and moves over land, collecting nutrients, soil, oil and debris before ending up in asphalt channels that abound in that area.

The new diffuser pond breaks that stream. It diverts the polluted stormwater from the asphalt channel into a grassy channel (similar to those that we installed in other areas around the Exit) allowing the water to “infiltrate” – to be absorbed into the ground.

Randy said, “This project is expected to divert tens of thousands of gallons of polluted stormwater, and dozens of pounds of harmful nutrients, away from the Lake each year. All that will help to preserve the water quality.” 

The water that is not infiltrated into the channel is directed into a rock-filled depression on the hillside that creates a stormwater pond. The water then infiltrates into the sand and rock installed under that pond, keeping the water, and all the nutrients inside, out of the Lake.

diffuser pond next to Northway Exit 22 southbound

Almost directly above the work next to Northway Exit 22 southbound, crews create a ‘diffuser’ pond to capture and infiltrate polluted stormwater before it reaches the Lake and degrades the water quality.

A view of the work from the bridge over the Northway.

A view of the work from the bridge over the Northway.

The channel and pond are built to handle 90 percent of storms.  But when we have another significant rain event (like the 3.4 inches of rain we had on August 4), the stormwater may overtop the pond. In that case, the water flow will mostly diffuse through the rocks into the surrounding property, at speeds and depths that will keep it far from the Lake.

“We are thankful to have partners like the New York DOT and the Soil and Water Conservation District,” said Walt Lender, the LGA’s Executive Director. “We appreciate that they, also, have the best interest of Lake George at heart.”

“Even with the pandemic, it has been a busy summer for projects,” said Randy. “We are happy the DOT is interested in these innovative ideas, and are expending considerable efforts to help protect the Lake’s water quality.”

For more information, please call (518) 668-3558 or see the wealth of information on our updated website at

The Lake George Association is the oldest and most experienced lake protection organization in the country, whose members support water quality protection, water quality monitoring, education and lake-friendly living programs that benefit the watershed from Lake George Village to Ticonderoga.

All the money raised by the Lake George Association goes to projects and programs that benefit the Lake and the watershed, protecting Lake George water quality now and in the future.