Park County planning board recommends approval of Windler (Rigler) Riverside subdivision with conditions after debate over river setback

The Park County Planning Board voted unanimously Dec. 18 to recommend approval of the Rigler (also referred to in the staff report as Windler) Riverside Tracts 1st minor subdivision to the county commissioners, while imposing conditions intended to protect the Yellowstone River corridor and local wildlife.

Mike Inman, senior planner for Park County, told the board the applicants propose four residential parcels of roughly 2–3 acres near Corwin Springs along the Yellowstone River, accessed by two shared approaches off U.S. Highway 89. The application relies on individual domestic wells and septic systems for each lot. “This is a 1st minor subdivision,” Inman said, noting the proposal is reviewed under the Park County Subdivision Regulations and is exempt from an environmental assessment and from certain dedications normally required for larger subdivisions.

Why it mattered: Fish, Wildlife & Parks (FWP) submitted a substantial comment letter recommending a 300‑foot development setback (250 feet of vegetative buffer plus an additional 50 feet for buildings) to protect riparian habitat and fisheries. Staff’s hydrology review showed the applicants’ estimates — prepared by a hydrologist — are based on single‑family residential use and a conservative 500 gallons per day per lot for groundwater impacts; the hydrology report also assumed each lot could include a 100‑by‑100‑foot irrigated landscape area requiring about 2.5 acre‑feet in a growing season. Inman said those assumptions were the basis for his finding that groundwater impacts would be minimal under the proposed use, but he added conditions to address FWP’s concerns and public‑safety risks from riverbank erosion.

Board discussion focused on three linked questions: the FWP setback and how it would affect developable lots, the siting of septic drain fields and mixing zones relative to erosion risk, and how water use and permitted uses should be limited. Inman summarized staff’s recommended conditions: require restrictive covenants making each lot single‑family residential, prohibit domestic sheep and goats (FWP’s primary disease‑transmission concern for bighorn sheep), require wildlife‑friendly fencing, and require a stormwater management plan consistent with DEQ Circular 8. “If what they’re basing their analysis on is single‑family residential, then that’s what we should permit,” Inman said during deliberations.

Applicant response and public comment: George Bournemouth, a land surveyor representing the applicants, and Cindy Rigler, one of the landowners, told the board they would accept several of the conditions — including limiting sheep and goats and adding wildlife‑friendly fencing in the covenants — but argued a strict 300‑foot setback would not be practical on this parcel and would reduce the project to two developable lots as currently drawn. “We do have a covenant that prohibits goats and sheep,” Bournemouth stated, and the applicants agreed to make single‑family restrictions part of the final covenants. Environmental advocates urged the board to adopt all staff‑recommended measures. Carrie Kale of the Park County Environmental Council said she supported staff’s conditions and warned that the Yellowstone River headwaters require careful protection.

The board’s amendments and final action: After extended exchanges about how to balance wildlife connectivity, private property rights and public‑safety risks from erosion, the board agreed to three clarifications to staff’s draft conditions: (1) require that any irrigated landscape be limited to a 100‑by‑100‑foot area per lot as included in the hydrology analysis, (2) maintain a prohibition on domestic sheep and goats and restrict other livestock to the extent necessary to stay within the submitted water‑use and septic analyses, and (3) prohibit perimeter or boundary fencing while allowing a small fenced protective enclosure (roughly 10,000 sq. ft. / 100x100) immediately around a residence for safety and livestock control. The board also left in place the requirement that the applicants submit a stormwater management plan consistent with DEQ Circular 8 and that they file covenants on the plat that cannot be modified without county commission consent.

Following the amendments, the planning board moved and seconded a motion to approve the staff findings and conditions as amended. The board voted 5‑0 to recommend approval to the Park County Commission with those conditions. The recommendation will be forwarded to county commissioners, who have final authority on subdivision approval.

What’s next: The applicants may revise lot lines or house locations to meet the conditions before final plat approval; staff noted the applicants have up to three years from preliminary approval to satisfy final plat conditions. The county’s staff and planning board emphasized that if the applicants want commercial uses, guest houses, larger irrigated areas or livestock beyond what the hydrology and septic analyses assumed, they will need to reconfigure the application and supply new analyses showing those uses would not harm groundwater, surface water or riparian habitat.

Board members and staff also signaled that subdivision regulation updates and the county’s growth policy review are ongoing and may affect future development standards.