The Carlisle Mosquito Online

Friday, October 1, 2004


ConsCom considers boardwalks and beaver dams

The Conservation Commission welcomed two diversions from last week's plethora of routine Requests for Determination (RDAs) and Notices of Intent (NOIs) and considered citizens' solutions to Nature's challenges. The first concerned a Trails Committee project and the other the unceasing labors of certain furry, flat-tailed engineers.

River Trail boardwalks

First, Steve Tobin, Bert Willard and National Wildlife Refuge Manager Libby Herland sought approval for installation of two boardwalks, 140- and 180-feet long respectively, on the River Trail in the Great Meadows Refuge. According to Tobin, these sections of the path are the last to become passable each spring. In fact, one of them hasn't completely dried up yet this year.

The first problem area spans an intermittent stream in the Refuge, while the second lies just beyond the community gardens at Foss Farm. Herland revealed that she had been able to get $5,000 to pay for materials for the project "because the Trails Committee had done such a good job of planning it."

Tobin told the commission his team planned to use six-inch galvanized pipe filled with cement to anchor the structures. These supports would then be dropped into holes drilled at intervals along the trail. The presenters were quick to adopt a suggestion from Commissioner John Lee that they use dry cement to fill the holes and let the moisture in the ground "wick up" the cement, thus lightening the load when transporting the building materials into the woods. After a brief look at the specifications and calling the application "a great plan" the commission approved construction.

Dam "engineers" raise water levels

The final agenda item concerned a plan for alleviation of flooding conditions near the Maple Street bridge. Brook Street resident Paul Sheedy showed photographs of the high waters emanating from Pages Brook, which have reached 100- to 150-year flood levels and are fast approaching his home. He also informed his audience that one of two spillways at the town-owned Greenough dam is clogged and warned that soon water will have to go over the top. The culprits, of course, are two extended families of beavers who have rebuilt dams near the bridge almost as fast as the department of Public Works has been able to demolish them.

Relaying data he had gleaned from the Internet, Sheedy said there are three admittedly temporary solutions: removing the animals, taking down the dams, and using flow-control devices. The third option is expensive and requires heavy maintenance. Sheedy had already obtained permission from the Board of Health to trap beavers to remove a threat to public health, and was asking ConsCom to approve destruction of the dams.

Commissioner John Lee, who is familiar with beaver problems, felt that the recommended moves could bring the water down to "a normative level" for this time of year, while Commissioner Tom Schultz warned that the town could never solve the problem for long, but that removing the dams would certainly lower the water level for a time. Watson suggested that Sheedy consult Cranberry Bog farmer Mark Duffy "who has extensive experience with beaver activities."

The commission congratulated Sheedy for the thoroughness of his presentation and issued an Emergency Certificate for lowering the water level to alleviate a public health threat to the residence at 428 Brook Street.

2004 The Carlisle Mosquito