Conservation panel gives positive advisory for Costello curtain drain, urges wetland stewardship

The New Shoreham Conservation Commission on Dec. 9 issued a positive advisory for a proposed subsurface perforated (curtain) drain at Mark Costello’s Corn Neck Road property, concluding the system is intended to relieve seasonal standing water without increasing impervious area.

Sergio Geranzio of Geranzio and Associates told the commission the project is under dual jurisdiction — the Rhode Island Department of Environmental Management (DEM) and the Coastal Resources Management Council (CRMC) — and that the project team has already filed with DEM but needs local sign‑off to proceed with CRMC review. "The purpose of that underdrain is that he gets a lot of ... his lawn in that area is just simply saturated with standing water," Geranzio said, explaining the perforated, gravity‑driven pipe is intended to speed drainage during drier periods and is not a pumped discharge.

Commissioners pressed on whether earlier drainage from Costello’s lot could accelerate flow into the town swale and a 12‑inch culvert that outlets to coastal waters. Geranzio replied the underdrain will discharge into the roadside swale through the soil and that "it's not gonna be shooting water through" as a forced conveyance; he said the swale and culvert currently control outflow and that the curtain drain would not increase the engineered peak flow because it operates by infiltration and gravity.

The commission also raised concerns about fertilizer use on a property that connects to both freshwater and saltwater wetlands. Geranzio said DEM/CRMC typically do not regulate homeowner fertilizer use on single‑family lots but that the applicant would consider best practices — such as organic slow‑release products and soil testing — and was open to recommendations. Chair Sue Gibbons moved that the commission issue a positive advisory and "that Mr. Costello consider being an excellent steward of his wetlands" with regards to lawn care; the motion was seconded and passed by voice vote.

Commissioners asked staff to confirm the project’s biologist report in the commission packet; the applicant said the report was submitted with the DEM application and would be re‑sent to the commission. Next steps: with the local advisory in hand and DEM documentation verified, the applicant will pursue CRMC sign‑off per the dual‑jurisdiction review process.