Found at - https://www.providencejournal.com/story/news/environment/2015/03/12/snow-melt-poses-hazard-to/35020429007/ The Providence Journal 2015-03-12
Snow melt poses hazard to waterways
Alex Kuffner? Journal Staff Writer
akuffner@providencejournal.com
(401) 277-7457

Water bodies that are close to heavily-traveled roads, such as Blackamore Pond near Route 2 in Cranston, are most susceptible to contamination from run-off.

The Providence Journal / Kris Craig PROVIDENCE, R.I. — The warm weather may be a welcome relief in this never-ending winter, but the melting of all the snow on the ground has environmental groups worried about salt, sand and pollutants running into the state’s water bodies.

While some of the runoff will be cleaned up at wastewater treatment facilities, much of it will not, meaning not just this winter's record-breaking amounts of snow will enter waterways, but also salt and sand as well as oil, grease and other chemicals from roads.

“It’s certainly something that we’re concerned about,” said Elizabeth Herron, program coordinator for the University of Rhode Island’s Watershed Watch. “It’s not just snow. You see all the sand mixed in and all the litter in there. All of that getting washed into the water can be a problem.”

When sand gets into waterways it can have a scouring effect and damage aquatic plants. It can also smother the eggs of bottom-dwelling creatures.

But salt is the main concern in freshwater lakes and ponds that can be most vulnerable to runoff. A stream or river can flush itself out, but that’s not so true for enclosed bodies of water. Frogs, salamanders and other amphibians are at particular risk when salt — or chloride — levels increase, said Herron.

“Chloride gets used by things, but it takes a long time to get out of the system,” she said. “For freshwater animals, it can have a significant impact.”

In Providence and the surrounding communities served by the Narragansett Bay Commission, some of the snow melt enters the treatment system and is cleaned up just like wastewater, said commission spokeswoman Jamie Samons. Sand and silt are removed in grit tanks and then taken to the Central Landfill in Johnston. Salt is treated through biological processes.

But in most of the state, stormwater isn’t treated. Water bodies that are close to heavily traveled roads are most susceptible. They include Blackamore Pond near Route 2 in Cranston and Lake Mishnock near Route 95 in West Greenwich. Both have seen escalating chloride levels in recent years, according to data collected by Watershed Watch.

The program collects samples for much of the state from May to October when water bodies are usually in use. One of the few watersheds monitored year-round is Buckeye Brook in Warwick because of its proximity to T.F. Green Airport, where de-icing fluids are used in the winter.

Members of the Buckeye Brook Coalition take samples throughout the area every two weeks and also after major snow events to check the extent of chemical runoff. Coalition vice president Paul Earnshaw said that last winter they saw rates of dissolved solids, including sand and salt, climb noticeably when the snow melted. When they next take samples, this weekend, he expects the numbers to spike again.

“I can assure you that the rate of dissolved solids will be very high,” he said.

The airport has taken steps to control runoff and is finishing a storage and treatment facility for de-icing chemicals. The approximately $30-million facility has collected 1.7 million gallons of fluids since October and expects to begin treating them in May, according to airport spokeswoman Patti Goldstein.

That’s the type of action organizations like the Conservation Law Foundation want to see more of. The Boston-based group has filed an intent to sue the Environmental Protection Agency for failing to enforce the federal Clean Water Act in Rhode Island and Massachusetts, citing particular damage from runoff from industrial and commercial properties to Mashapaug Pond, the last remaining natural pond in Providence, and water bodies on Aquidneck Island.

"The snow melting is a stark reminder that stormwater is an issue for Rhode Island," said Tricia Jedele, Rhode Island director for the CLF.

Tom Kutcher, baykeeper for Providence-based Save The Bay, said that one answer in dealing with snow-melt is building catch basins to trap sand and the pollutants that stick to it, such as oils and metals. They’re the biggest problems for Narragansett Bay and other salt-water bodies.

“You can’t catch it all, but you can get most of the pollutants,” Kutcher said.

For freshwater ponds and lakes, Herron said reducing the amount of road salts helps. She pointed to New Hampshire, which has worked aggressively to cut down on salt use after freshwater ponds and lakes near Route 93 were found to have toxic levels of chloride.

The Rhode Island Department of Transportation has reduced annual salt use since 2007 by 27 percent, according to a 2014 Statewide Planning report. The five-year average for use was 85,000 tons, though in the 2013-14 winter 130,000 tons were used. It’s unclear how much was used this winter or whether the DOT is working to further reduce salt use. The agency did not respond to multiple requests for comment.

Angelo Liberti, chief of surface water protection at the state Department of Environmental Management, said the problems with runoff shouldn’t be too bad if the snow melts gradually over a number of days. Sand will stay on roadways, where it can get swept up. Pollutants will also be less likely to get washed into waterways.

But a heavy rainfall could cause problems, creating what Liberti called a “double-whammy effect.”

Samons, of the Narragansett Bay Commission, agreed. “Hopefully, we’ll get a nice, slow thaw,” she said.