Longmont council approves phased rezoning and land‑use amendments to transition Erwin Thomas gravel mine toward housing and mixed‑use development

Longmont City Council on Tuesday approved a package of rezoning, concept plan and final development plan amendments to enable phased transition of the Erwin Thomas gravel‑mining property to urban development. The council approved five ordinances that reconfigure land uses, rezone portions of the site and allow phased removal of the property from the existing Planned Unit Development (PUD) for reclamation and redevelopment.

Barbara Brunk of Resource Conservation Partners, speaking for Diamond G Concrete Company, summarized a multi‑year, phased approach that keeps mining and reclamation in sequence and prepares the first phase of reclaimed land east of Harvest Moon Drive for development. Brunk said the application adjusts the land‑use plan so a larger mixed‑neighborhood area can be developed across from earlier affordable‑housing sites, and creates two phases of PUD amendments so mining operations and development can proceed without pausing the larger reclamation work.

Why it matters: The approvals convert parts of the 209‑acre site from an industrial mining PUD to zoned land intended for residential, mixed‑use and single‑family development. Project proponents emphasized an opportunity to add a range of housing types, including potential attainable for‑sale product, and to create pedestrian connections, ponds and habitat areas while staging mining and reclamation.

Key features approved by council: - An Envision Longmont land‑use amendment and concept‑plan change to reconfigure the southern portion of the annexed property for mixed‑use corridor, residential mixed‑neighborhood and single‑family uses. - Two rezonings that change portions of the land from PUD to straight zoning (Mixed Use Corridor, Residential Mixed Neighborhood, Residential Single‑Family) in a phased fashion. - Two final PUD plan amendments to remove the areas south of the highway from the PUD in two stages, allowing the initial reclaimed parcels near Harvest Moon Drive to be developed first. - A condition allowing up to a 25% increase in overall density on the concept plan through a staff review process, which planners said is intended to allow modest flexibility without requiring a full concept‑plan amendment for minor unit adjustments.

“It's the goal…to reconfigure the land uses so they can be developed consistent with what's happening on the ground,” Brunk told council, and she described design elements that aim to create a variety of housing types and pedestrian connections around ponds and drainage corridors. Planning staff noted the project will proceed through standard preliminary‑plat and site‑plan reviews under the new zoning; items requiring conditional use review would still come to council if applicable.

Councilors asked about the mix of housing and whether the zoning allows neighborhood‑serving retail; Brunk and planning staff said the Mixed‑Use Corridor zoning permits commercial uses and that further site design, preliminary plats and development plans will determine the final mix and placement of retail and residential uses.

Next steps: Developers and staff will proceed with preliminary plats, site plans and infrastructure design under the new zoning. Council approved the ordinances on the consent/second‑reading sequence for the project (2025‑56 through 2025‑60), allowing the phased reclamation and first development parcels to move forward.

The vote to approve the package was unanimous. Councilors and staff described the approvals as reconfiguring an annexed mining property for future neighborhood development while retaining staged reclamation and safety controls during the mining phase.