Planning commission recommends Lamar's Landing PUD, approves variance to use HDPE storm pipe

The Newcastle Planning and Zoning Commission on Aug. 25 recommended approval of a planned unit development rezoning for Lamar's Landing, a proposed 48.59-acre mixed commercial and industrial project on State Highway 9, and unanimously recommended a variance to permit ADS N12 HDPE storm sewer pipe encased in engineered fill in place of reinforced concrete pipe.

The project applicant, Aspen's Land Development LLC, seeks to subdivide the property into three blocks: Blocks 1 and 2 for commercial uses under a C‑C2 commercial zoning standard and Block 3 for heavy-industrial uses. Planning staff described a PUD that would allow restaurants, auto‑service (excluding salvage operations), marquee signs at the development entry, and heavy-industrial uses such as concrete and asphalt batch plants in the rear block. The preliminary plat proposes three public access points, a centrally located detention/wetland feature to meet the city's drainage requirements, and interim gravel frontage improvements along Southeast 40th Street.

Keith Johnston, the city's development review coordinator, told commissioners the site will be served initially by on‑site wastewater treatment (individual septic systems) until a gravity sewer can be extended to the development; the proposal meets the Oklahoma Department of Environmental Quality requirement for on‑site systems on lots at least one‑half acre in size. Johnston also said the final plat and public improvements will be subject to a development agreement and must be approved by city council before construction begins.

Engineer John Bolti of Small Arrow Engineering described the site's drainage and hydraulic work and explained why the applicant is requesting a variance to the city's typical reinforced concrete pipe requirement. Bolti said the project's flat topography, shallow groundwater and limited cover make meeting the minimum pipe grades difficult with reinforced concrete pipe because larger diameters would be required. "It's like 0.13 for concrete, 0.12 for poly," Bolti said when comparing Manning's coefficients; the design team concluded HDPE, encased and installed per manufacturer recommendations, would allow the required hydraulic performance without oversized pipe and excessive cover. The engineering team also reported a HEC‑RAS backwater analysis showing about a 1.2‑inch increase in the local water surface after the project's wetland/detention work, which staff said remains within allowable limits and for which building pads will be set 1 foot above the computed base flood elevation.

The commission discussed interim road improvements along Southeast 40th Street, the proposed collector cross‑sections that will connect to State Highway 9, and the project's plan to construct a central wetland/detention pond to control post‑development flows. Staff told commissioners the applicant has coordinated with the city and addressed staff comments; any developer participation for upgrading Southeast 40th to city standards will be negotiated in the final plat/public improvement stage.

After the presentation and questions, a commissioner moved to recommend approval of the rezoning and the requested variance to use HDPE storm sewer pipe; the motion carried unanimously.

If the city council approves the rezoning and final plat, each lot will require site‑specific building permits, floodplain elevation certificates and other conditions identified during the final plat process. The final plat, development agreement and any public improvements must be approved by city council before construction begins.