The Planning Board at its meeting Monday night discussed the stormwater management plan for the construction project proposed for the Elmwood Farms III subdivision.

Principal Planner John Gelcich explained that the original Blueberry Lane subdivision was approved in the late 1980s and constructed from the late 1980s to the early 1990s. However, a portion of the project was never built.

“In Massachusetts, when subdivisions are approved and substantially constructed, they are essentially approved forever,” he explained. “The remaining lots can be constructed at any point in time, and the requirements for what they are constructing are locked in at what they were when they were approved.”

Toll Brothers purchased the remaining lots, which are surrounded by proposed roads Fitch Avenue and Myrtle Avenue and the formerly proposed Adams Street.

Gelcich added that the developer has agreed to update the stormwater management system to be compliant with current regulations even though it is not required to do so “given the existing stormwater issues in that area.”

Because the wetlands there have changed over time, four lots have been deemed no longer buildable. Adams Street will no longer be constructed due to the Conservation Commission’s vote to eliminate it. The unbuildable lots will merge and have a conservation restriction placed upon them.

The Planning Board had voted 7-0 to endorse the plan in November for the construction of 20 lots in the new subdivision.

Ted Merchant, the land development director with Toll Brothers, explained that the town advised the applicant to update the stormwater system in the subdivision “to benefit the rest of the community.”

Matt Ashley, the applicant’s civil site engineer from Bohler Engineering, said the stormwater management system will collect runoff throughout the development. It will run along Fitch Avenue and most of Myrtle Avenue to the existing stormwater basins off Blueberry Lane.

A drainage swale is planned behind all of the units, he added. Water will go into an underground stormwater network and into the proposed stormwater management system “to provide a better route,” according to Ashley. Also, the number of infiltration basins was doubled for all of the houses.

Comments on the plans were received from the Department of Public Works and the Health Department. DPW noted that it would accept the proposed roads without stormwater management improvements. The town’s peer review engineer also is to review the plans.

Planning Board chair Gary Trendel said he was “cautiously hopeful” that the stormwater management plan would be “a substantial improvement” that will be effective in controlling the water flow that now travels to Blueberry Lane.

Neighborhood residents questioned Ashley about the impact the development would have on their properties. Blueberry Lane resident Caitlin Lombardi asked whether there would be any proposed improvements to the present drainage system. She also noted that the construction of the new elementary school building near the subdivision likely would cause additional stormwater runoff.

Ashley said the existing stormwater basins will be improved. There is nothing proposed “in Blueberry Lane itself.” While the stormwater analysis did include the hill where the school would be built, it did not encompass the entire school property.

Other residents raised concerns about how the construction of the subdivision will impact water flow and pooling. The planned trail there also was discussed, but there was no update available about its construction.

Gelcich added that there is no way to determine the potential runoff from the school construction because the plans have not been finalized. The school also will need a stormwater management permit.

Trendel thanked the residents for their questions, saying that they “make this a better site.”

The hearing was continued until the March 4 meeting. A site walk will take place on Saturday.

MBTA Communities Act compliance plan mentioned

Trendel said the Planning Board is awaiting the final recommendation from the Zoning Advisory Committee (ZAC) on its proposed plan to comply with the MBTA Communities Act.

Gelcich noted that the consultant who has expertise on this state law will prepare a report on the final plan and will appear at the March 4 meeting to answer questions.

The only public feedback came from Eric Wieland, a board member of The Preserve, who spoke at previous meetings about the potential impact to the homeowners there. He questioned why development couldn’t occur on the state land on both sides of Route 85.

Trendel noted that land is part of Hopkinton State Park, which is under a conservation restriction.

Draft stormwater regulations received

Gelcich noted that a draft of proposed stormwater regulations was received from Tighe & Bond, the DPW’s engineering consultant. The town is seeking to update its stormwater regulations to account for climate change’s effect on precipitation calculations. It also wants to bring the town into alignment with the state’s MS4 permitting requirements.

He added that the state’s Department of Environmental Protection is updating its stormwater handbook, which communities tie to their regulations. The draft currently is in line with the handbook. It will be discussed at the March 4 meeting.

Board approves Town Meeting articles accepting open space land donations

The Planning Board voted 7-0 to add to open space acceptance articles for land donations from the Whisper Way and Emerald Drive (formerly called Connelly Farm) subdivisions to the warrant for May’s Annual Town Meeting.