Planning board presses engineer after plastic culverts and uncoordinated work found on Tanya Lane and RiverRun

Brentwood Town Planning Board members pressed engineering consultant Chris Raymond of TEC on April 3 after field inspections found plastic (HCPE/ABS) driveway culverts on Tanya Lane and a separately installed plastic drainage pipe at RiverRun that had been paved over.

The board said the installations conflicted with the town's standards and that communication breakdowns after a withdrawn waiver left planners and the consultant unaware of final materials. "It's used all over" for plastic culverts, but "I really don't see ... from a durability standpoint any issues there," said Chris Raymond, an engineer with TEC, describing industry practice for HCPE pipe in low-traffic residential driveways.

Board members said the problem is not only material choice but process: members asked for regular field reports, clearer distribution of inspection notes and prompt notifications when inspectors find noncompliant work. One planning board member urged that "the board needs to be notified of those corrective actions and what actions are being currently taken to correct them." The board told TEC it expects the consultant to alert staff and the board immediately when corrective measures are required, not merely document them.

Why this matters: Town acceptance of roadways and long-term maintenance responsibility depend on work meeting Brentwood's standards. If nonconforming materials remain in town right-of-way after road adoption, homeowners may inherit costs or the town may have to require retrofits before acceptance.

Details and timeline: TEC said the Tanya Lane plans included a note stating "all pipe would be plastic unless otherwise noted," and that a waiver related to pipe material was submitted then withdrawn. Raymond said TEC conducted engineering review and periodic inspections; in one case a representative inspected RiverRun this week. For RiverRun, TEC documented a contractor-installed plastic pipe last April intended to alleviate ponding; construction later paused for nearly a year and the pipe was blacktopped over. TEC has placed the item on a punch list and the developer's design engineer has proposed replacing the pipe with reinforced concrete pipe (RCP) to meet the town's ordinance.

Board members reiterated that construction changes must be routed through the town engineer or planning staff. Planning staff members acknowledged the town's historical turnover in points of contact and said they will institute biweekly field-report sharing and tighter follow-up after waiver withdrawals. The board also asked the consultant to include corrective-action items in the shared project folder and to send immediate alerts when noncompliance is found.

On technical fixes, TEC noted that small driveway culverts (commonly 12-inch) installed as HCPE in low-traffic residential driveways are widely used and generally durable; the board's concern centers on culverts located in the town right-of-way, where snowplow damage and long-term maintenance favor reinforced concrete pipe and reinforced headwalls. Raymond said adding concrete headwalls would strengthen ends but may add maintenance obligations.

Next steps: TEC will provide biweekly field reports to town staff, the consultant and the planning board; the developer has proposed replacing the RiverRun pipe with RCP, and the board asked staff to confirm that remedy is completed before any road-adoption action tied to that segment. The board also asked planning staff to review the town's contract with TEC and bring a revised contract with clearer reporting expectations.

Ending: Board members said they will continue site visits and asked residents and board members to document and pass along photos or video of any suspected noncompliant work. TEC and planning staff agreed to increase communication and to return to the board with confirmation once the RiverRun repair is complete.