Foundry Row project approved for drainage variance after engineering review

Delaware County commissioners on July 7 approved a drainage variance for the Foundry Row commercial development on Cowan Road after hearing technical details from the developer's civil engineers and county staff.

The vote matters because it permits a deviation from the county stormwater manual's cover requirements in order to allow storm sewer placement in the site's parking areas; the developer and county engineering staff said the project upgrades pipe strength and minimizes new discharge while demonstrating downstream capacity.

Alex Stevens, civil engineer with the project team, told commissioners that the site is flat and required substantial fill to gain depth for conventional storm‑sewer inverts. To address the shallow cover, engineers proposed using a stronger Class‑4 reinforced concrete pipe and maximizing detention to minimize discharge. Stevens said the project team worked with Versus Engineering (the county's third‑party drainage reviewer) and the county engineer to identify a design that preserved system capacity. "We have ... maximized the size of our detention and minimized the discharge, but more importantly shown that the downstream culvert and the ditch ... has capacity for what we're proposing," Stevens said.

Commissioners asked whether the installations would be under parking areas and whether the upgraded pipe class would withstand truck traffic; engineers confirmed the pipes will be in parking areas and that the Class‑4 reinforced concrete pipe was selected to permit reduced cover while sustaining loads.

A motion to approve the drainage variance passed on roll call with Commissioners Reagan, Brand and Henry voting yes.

The approval allows the developer to proceed with the revised drainage plan subject to engineering conditions and inspection; the county engineer will monitor construction and require compliance with the approved design.