The Carlisle Mosquito Online

Friday, January 25, 2008


Planning Board reviews Hanover Hill subdivision

Safe roadways are a major priority during Planning Board review of proposed developments. The board sought to ensure that sight lines are adequate for traffic around the 35-lot Hanover Hill subdivision planned for Westford Street, as they discussed the project on January 14 with Hanover Hill engineer George Dimakarakos (Stamski & McNary) and the applicant's traffic consultant David Friend (Transportation Planning Services).

The definitive subdivision plan shows one new subdivision road (Hanover Street) entering Westford Street at the Cross Street intersection and the other new road (Johnson Road) entering the main road near the house lot at 546 Westford Street (see map at right). The consultant presented sight line data for "intersection sight distance" (ISD) which had been requested by the board. This is the distance that a vehicle driver exiting from the subdivision road can see in both directions before merging with traffic. He referred to data tables that relate needed ISD to speed of main road traffic such that an oncoming car need not reduce its speed to less than 70% of its original speed in order to accommodate the car entering traffic. Given these criteria, he said that both subdivision road locations gave an ISD of at least 400 feet and thus would accommodate a travel speed of between 35 and 40 miles per hour on Westford Street. Board chair Michael Epstein said that its consulting firm Nitsch Engineering, reported data that was more pessimistic but, lacking specifics on the criteria used by Nitsch, he would discuss the discrepancies with the board's consultant.

The present speed limit in this part of Westford Street, between the proposed Johnson Road and Cross Street, is 35 miles per hour. On the hill between Cross Street and Acton Street there is a 30 mph section. Data in an August 2007 Traffic Analysis Report previously submitted by Friend indicated that the weekday travel speeds between the two proposed subdivision roads for the two days monitored were between 39 and 44 mph for the 85th percentile — that is, 85% traveled at or below this speed, while 15% traveled above it.

Fire Department review

David Flannery, Fire Department Chief, reported on his review of the subdivision plan, including the three water cisterns, road width, cul-de-sac turning radii, T-turnaround dimensions, and private common driveway details. He was generally satisfied with the details presented. However, he said that the Fire Department typically requests that private common driveways that serve three lots or more be 16 feet wide with two foot "hard shoulders." This is wider than required by the Planning Board.

Footpaths and trails

The Planning Board Rules and Regulations Governing the Subdivision of Land require the developer to construct footpaths.

"Section 5.C. Footpaths: (1) Footpaths shall be required by the board to improve circulation and connections within existing, proposed and potential future subdivisions, streets and ways unless the board determines that safe pedestrian travel is otherwise provided.... The footpath shall be on at least one side of the street. In addition, the board may require the installation of pedestrian ways, trails, bridle paths, bicycle paths and/or Footpaths where deemed necessary to provide adequate circulation."

"(2) Footpaths may, in appropriate circumstances, be requested to be constructed along existing roadways.

"(8) If approved by the board, the applicant may, in lieu of the installation of all or some of the footpaths in the subdivision, contribute funds to the Town to mitigate the adverse impact of the subdivision on pedestrian safety and vehicular traffic at a rate of $15 per linear foot based on the length of the footpaths that otherwise would have been required by the board. The contributed monies shall be deposited in the 'Carlisle Pathway Account' for the use of constructing and maintaining footpaths and trails in Carlisle."

John Bakewell of the Pedestrian and Bike Safety Advisory Committee reported on discussions with the developer, Rob West. Rather than footpaths within the development, the committee is advocating a paved footpath along Westford Street from the subdivision roads to Virginia Farme. Henry Cox and Steve Tobin, representing the Trails Committee, would like a trail from the cul-de-sac at the end of Virginia Farme Lane into the development to Hanover Street.

An abutter to the proposed Westford Street footpath, Kate Rowan (19 Virginia Farme), had some reservations: "We thought we left sidewalks when we moved from Charlestown." She indicated that the present trees and shrubs provide desirable cover between their home and Westford Street.

Drainage and low impact development

Dimakarakos reported on discussions with Nitsch Engineering, the board's consultant, on the topic of Low Impact Development (LID) as applicable to Hanover Hill.

The Massachusetts Executive Office of Environmental Affairs defines LID as "an approach to environmentally friendly land use planning. It includes a suite of landscaping and design techniques that attempt to maintain the natural, pre-developed ability of a site to manage rainfall. LID techniques capture water on site, filter it through vegetation, and let it soak into the ground where it can recharge the local water table rather than being lost as surface runoff."

Dimakarakos told the board, "You take the site and do what you can. Given this site I've gone as far as we can go." He said that runoff from roofs is handled on each individual lot, runoff from driveways does not flow onto roadways, and infiltration areas and infiltration trenches are provided.

Specific discussion centered on a plan detail of the intersection area opposite Cross Street provided as an "exercise" by Dimakarakos. It showed considerable tree clearing to provide a water runoff infiltration area intended to eliminate catch basins and piping to carry the runoff back into the development. He did not support this approach although it was advocated by Nitsch Engineering. He said that it would adversely affect the "streetscape" and might not totally eliminate the need for catch basins in that area. Associate member David Freedman volunteered to continue the discussion with Nitsch and to consult Gary Davis, head of the Department of Public Works, and to report back to the board.The hearing will be continued at 8:15 p.m. on February 11.

Planning Board

hears technology complaints

Near the end of the meeting Epstein commented that some material he had requested for the board from planning administrator George Mansfield could not be provided because of computer problems which have been chronic for several months. Board member Carol Nathan noted that the Council on Aging is still waiting to have its computer installed. Freedman said, "This seems to be the same situation that we had two and a half years ago. The Technology Advisory Committee was set up by the Selectmen, but I see no evidence of a plan to do anything different." Vice chair Greg Peterson said, "It is ironic given the time and energy expended on technology at the school and at the town offices. I don't understand how we [the Town Office] can function."

Meeting schedule

Epstein announced cancellation of the January 28 meeting since it conflicts with an important Finance Committee (FinCom) meeting. The Conservation Commission, Board of Health and Planning Board are scheduled to meet with FinCom that evening.

The next Planning Board meeting will be February 11, when an application by Omnipoint Communications, Inc. will be addressed. The application is for a special permit and site plan approval to install a personal wireless facility within the steeple of the First Religious Society (27 School Street). This facility, if approved, will be located below the Sprint wireless facility previously approved by the board.

2008 The Carlisle Mosquito