Planning board holds Toll Brothers to engineer-verified drainage fixes; two final COs remain withheld

Tainesville Planning Board members pressed Toll Brothers on July 16 to provide engineer-verified evidence that subdivision stormwater basins function as designed before the town will issue two remaining certificates of occupancy for the Enclave/Kingsborough development.

Town engineering staff reported field observations showing standing water in multiple basins after more than a week without rain. "We were out there this morning. I think six of the nine basins there are, you know, close to a foot, if not, you know, a couple feet of water in some of them," the town reviewer said, and later listed basin depths including roughly 2 feet in Basin 2 and about 1.5 feet in Basin 3.

The town engineer described the performance standard for infiltration basins: they must drain within 72 hours. He said the board needs documentation proving either that the basins now meet the design infiltration rates or that soils on-site differ from the design test pits before the board will accept a change in approach.

Toll Brothers representatives said they built the basins as designed, have cleaned them and performed infiltration testing, and proposed a two-pronged path forward: verify whether the original test pits are representative and, if not, convert Basins 2, 3 and 5 to extended dry detention basins with underdrains so they will exfiltrate to the outlet rather than infiltrate into groundwater.

"We built the basins per design. We did clean them out. We performed infiltration testing. We had TEC present," one Toll Brothers representative said, adding the developer is willing to schedule further testing and to have town engineers present. The company's representative asked the board to clarify what evidence it requires.

Board members and residents pushed back on the pace of progress. Several members said that, even if cleaning had been attempted, the developer had not provided timely documentation to the town engineer; one member said that until engineers confirm fix and test results, the board would not consider design changes or lift the hold on the remaining certificates.

Multiple residents who are prospective homeowners told the board the withheld certificates have delayed closings. One resident who read a letter urged the board to consider alternatives such as a larger performance surety or escrow so families could close; the board replied that altering the town's contract terms to accept a surety in place of the contractually required completion would expose the town to risk and that the board would not change the existing contract.

The town's next steps: the developer agreed to deliver geotechnical reports and contractor documentation to the town engineer and TEC, schedule on-site inspections while work is performed, and implement cleaning or other fixes. The board directed the town engineer to specify the evidence required (infiltration test locations, test-pit descriptions, grading updates) and to re-evaluate the design valuations once the documentation is submitted. The board reiterated that it will not issue the final COs until the basins meet the engineer's exit criteria.