Salty water makes Westwood, Dedham push MassDOT for a 128 'no-salt zone'

After a conclusive case study proved the high level of chloride in the White Lodge Wellfield was caused mainly by the Massachusetts Department of Transportation, the Dedham-Westwood Water District is requesting that MassDOT make their section of Route 128 a reduced salt zone.

The study, performed by Kilbridge Geological Services and the civil and environmental engineering department at UMass Amherst, showed that three-quarters of the salt found in the White Lodge Wellfield Five came from the de-icing methods taken by MassDOT during the winter months.

After the water district first applied for a reduced salt zone in 2003, MassDOT hired the UMass Amherst CEE department to determine whether the high salt levels were due to MassDOT’s de-icing methods. Their findings would be considered to see whether a reduced salt zone would be necessary.

From 2007 to 2010, UMass and Kilbridge collected chloride data over three de-icing seasons, measuring the quality of the water and soil. They mostly measured chloride as the indicator of the type of chemicals present in the water supply, and showed MassDOT was the main contributor.

Currently, the Dedham-Westwood Water District holds up to 1.5 billion gallons of groundwater per year, and supplies drinking water to 38,000 users in two towns.

White Lodge Wellfield is one of five wells operated by the water district, and the only one that lies north of Route 128. It provides more than 70 percent of the towns’ water, pumping 100 gallons of water per minute to local homes in the area.

Paul Brown, MassDOT director of snow and ice operations, addressed the Dedham-Westwood Water District meeting held Tuesday, Dec. 27. He suggested a number of technological changes, including changing the hydraulic valves on the salting trucks from open loop to closed loop, which means the spread of salt would no longer be determined by the speed of the truck and instead be spread at a constant rate.

But the water district committee members were less interested in hearing Brown’s ideas than they were insistent that their request for a reduced salt zone be revaluated. If MassDOT complies with the request, the stretch of Route 128 running through the towns will have less salt service and more signage and other initiatives intended to increase public awareness that the area is environmentally sensitive.

Brown said those measures will not be enough to maintain safe roads during New England’s harsh winter months.

“Reduced level of service means, more snow, more packed ice and more issues,” Brown said. “We prefer to be proactive before we get into a no salt zone. It’s hard to maintain good and safe roads if we use less-than-perfect materials.”

Brown said the amount of salt used should be dictated by the severity of the storm and the conditions of the road.

He completely ruled out the idea of sand, which would ultimately cost the state more money and cause more damage to the ecosystem.

“Sand is a mineral that doesn’t melt any snow,” Brown said. “It’s good on low-volume highways and gravel, but for roads with faster vehicles and higher volume of traffic, you need something with chloride in it to create a chemical reaction.”

“In fact, sand does more harm than salt,” Brown said. “If it gets into waterways, it clogs, and subjects [the waterway] to more algae growth. It could eventually become marshland or a wetland. Sand needs to be vacuumed up, moved around and put in a landfill, which costs a ton of money. Everyone thinks sand is a panacea, and it’s not.”

Eileen Commane, Dedham-Westwood Water District executive commissioner, still hopes to work with MassDOT to bring down the salt levels within White Lodge.

“I think Brown did bring up some relatively new technologies that MassDOT can use to reduce the amount of de-icing compounds on the ground,” she said. “But from the board’s point of view, we have been taking this sodium issue on for a decade, and feel the best thing to be done is to establish that area of 128 as a low-salt zone.”

UMass professor David Ostendorf, who conducted the study, said it will take a few years for a noticeable reduction in White Lodge’s chloride levels. He also said making a lasting impact on the salt levels will take an effort from the towns of Westwood and Dedham, and not just MassDOT.

“Whatever you do, it is going to take a number of years to manifest in White Lodge,” Ostendorf said. “Not week, not a month, not a year. It will take a gradual change after a number of de-icing seasons to see results.”

“All parties need to be mindful of this,” he said, “Parties who haven’t been mindful, especially private sector people like developers, need to take caution.”

Contact correspondent Marc Filippino at westwood@wickedlocal.com.