The Needham Conservation Commission voted Oct. 23 to issue an Order of Conditions for a Notice of Intent for work at 46 Pleasant Street (DEP file 234-955) after staff and commissioners reviewed stormwater calculations and asked for a small plan clarification about drains for a proposed deck slab.

Montgomery Wistemski, the applicant’s representative, described plans to remove a back deck and stone patio, add an addition with a garage and a new deck, and install an on-site drywell designed to collect roof runoff. “We’re designing for the worst-case scenario,” Wistemski said, referring to a possible future roof over the deck. He told the commission the drywell and drainage calculations were sized to accept runoff from the existing house plus the proposed addition and a covered deck if it is built later.

Commissioners asked several detailed questions about impervious-area change (the NOI showed existing impervious at 1,206 square feet and proposed at 1,737 square feet) and whether trees would be removed; staff confirmed no trees were proposed for removal. Commissioners also requested perimeter drains for the deck slab so runoff from a slab (if the roof is not built) will be collected. Wistemski agreed the plan can show the additional drains and said the drywell had been sized to the calculated storage requirements.

After the discussion there was no public comment, and the commission closed the hearing and later voted to issue the Order of Conditions with a special condition requiring the applicant to provide the final deck-slab drainage detail and to record the operation-and-maintenance plan for the infiltration system.

The vote to issue the Order of Conditions passed by roll call: Sue (Aye), Reid (Aye), Clary (Aye), Bill (Aye), Paulina (Aye) and the chair voted Aye.