Arapahoe County commission approves Box Elder diversion dam, with legal and permit questions unresolved

Arapahoe County’s Planning Commission voted 5-1 on June 2 to approve Rangeview Metropolitan District’s location-and-extent application for the Box Elder Diversion Dam, a public-utility project on Boxelder Creek that drew heavy opposition from downstream landowners.

The vote matters because the Planning Commission is Arapahoe County’s final approving authority for location-and-extent cases, so the case does not automatically go to the Board of County Commissioners for another county land-use vote. But the June 2 action did not settle broader disputes over the project’s downstream effects or foreclose possible challenges in court or in Colorado’s water-rights system.

According to the county staff report for case LE25-005, the project includes an inflatable 3-foot-tall bladder dam, a stream gauge, a buried pumping vault and about 600 feet of 16-inch transmission line on a 1.5-acre easement on state land southwest of East Quincy Avenue and South Manila Road. The report says construction is projected to begin in summer 2026 and take about three months.

At the hearing, county staff told commissioners the county review was limited to the siting of a public utility under the land-development code, not the underlying water right. Rangeview’s engineer similarly told the commission the district already holds the Boxelder Creek water right and was seeking permission to build the diversion infrastructure, not revisit the decree.

The case also highlights a broader collision between land use and water supply in eastern Arapahoe County as Sky Ranch and other growth areas seek renewable supplies. The staff report says the diversion would support future phases of Sky Ranch, diversify Rangeview’s water portfolio and reduce demand on groundwater. Opponents argued at the hearing that the same project could harm the shallow-water system that sustains creek-bottom agriculture and habitat downstream.

More than a dozen residents and landowners told commissioners during the public hearing that Boxelder Creek supports cottonwood stands, livestock watering, shallow wells, sub-irrigated hay ground, migratory wildlife and year-round pools in some reaches. Several said county and wildlife review focused too narrowly on the immediate project area and did not adequately study downstream groundwater or ecological effects.

Applicant representatives responded that Rangeview’s decreed right is a junior flood-flow right that would allow diversions only when senior downstream rights are satisfied. They said the dam would generally remain deflated, that the structure is designed for up to 10 cubic feet per second, and that the state Division of Water Resources audits and administers those diversions.

Chair Randall Miller cast the lone no vote. He said before the roll call he favored denial because the recommended wildlife-related conditions were too vague and because he did not think the record fully addressed testimony about species and habitat along the creek.

What approvals remain is less clear. Arapahoe County’s floodplain rules say development in a floodplain or special flood-hazard area must obtain a Floodplain Development Permit before construction begins. At the hearing, county staff said the U.S. Army Corps of Engineers had approved a nationwide permit for work in the floodplain, and the staff report says Rangeview has a state-land easement for the site.

The county file and hearing record do not clearly show whether the county floodplain permit has already been issued, or whether any building or grading permits remain outstanding. The staff report says, citing the applicant, that “all construction permits have been granted for this project”, but the materials reviewed for this story did not independently document that claim.

The likeliest next battleground is outside another county hearing. Because the Planning Commission described the case as a quasi-judicial public hearing and issued a final local decision, opponents could seek district-court review under Colorado Rule of Civil Procedure 106(a)(4). That procedural path is described in a Colorado land-use legal explainer, which says such challenges typically must be filed within 28 days. Separately, any dispute over whether Rangeview diverts more water than its decree allows would fall to Colorado’s water-court and water-administration system, not the county land-use process, as the applicant and county staff told commissioners.

For now, the county has approved the project’s siting, but the fight over Boxelder Creek appears unresolved. The split vote, the organized turnout and the testimony about downstream land and habitat suggest the case has grown beyond a routine utility siting matter.