Levels of salt along I-93 in N.H. is focus of study
The New Hampshire Department of Transportation and the state Department of Environmental Services are about to embark on a yearlong study to determine why salt levels in the area of Interstate 93 in southern New Hampshire exceed environmental standards.
Road salt has emerged as the most contentious issue in widening a stretch of I-93 between Salem and Manchester. So much road salt from I-93 and surrounding roads and parking lots is seeping into some bodies of water in southern New Hampshire that it is threatening the organisms upon which fish and other species feed. It is the chloride in the salt that is toxic to those freshwater life forms.
Approximately nine streams exceed state and federal clean water standards for chloride levels, with at least two of them feeding into Canobie Lake, a source of drinking water for Salem. Transportation officials and environmental regulators suspect the chloride levels are high because of salting of I-93, other roads, and parking lots in the area during the winter. They also suspect that chloride from water softeners is contributing to the elevated levels.
The $500,000 study, which will tap researchers from Plymouth State University, will hopefully pinpoint the exact causes so the Transportation Department, municipalities, and businesses can craft a plan to reduce salt usage. The Transportation Department is determined to use the same amount of salt or even less after it widens I-93 from two to four lanes in each direction, said Bill Cass, assistant director of project development.
``We can do it with new and more efficient technology," Cass said.
The Transportation Department already has started to reduce its salt use. Two years ago, the department began spraying portions of I-93 with a mixture of salt and water before winter storm s strike, and then expanded the practice last winter.
The mixture, known as brine, helps prevent roads from icing over and reduces salt usage per lane-mile by about 40 percent. The department also is exploring other technologies that will tell salt truck drivers what the exact temperature of the road pavement is so they can adjust how much salt they are dispensing based on temperature.
However, Cass stressed, reducing chloride levels will have to be a joint effort by the state, local officials, and area businesses.
Cass said the study should not delay plans to widen I-93. He said that the department is seeking bids to build a new park and ride lot at Exit 5 in Londonderry, and that work on the first bridge replacement -- the Cross Street bridge in Salem -- should begin next year.
Help in obtaining
T passes, ID cards
As part of its implementation of a new fare-collection system, the Massachusetts Bay Transportation Authority continues its local effort of replacing all valid existing MBTA senior citizen identification cards and transportation access pass cards for persons with disabilities.
MBTA staff will be on hand Aug. 22 from 1 to 4 p.m. at the Arlington Council on Aging, 27 Maple St. They will take photos, issue temporary permits, and provide information on the new passes.
The MBTA staff also will be at the Woburn Senior Center, 144 School St., on Aug. 31 from 1 to 4 p.m.
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