Geyser

Judith Basin County (Stanford county seat; central Montana prairie between Great Falls and Lewistown; ~1,990 residents across 1,870 sq mi; one of Montana's smallest-population counties; ranching, dryland wheat, and outfitter economy with the Highwood Mountains on the northwestern margin and Square Butte (a prominent volcanic plug visible across the central plains) as the county's signature landform; the Lewis & Clark Trail crosses the northern county along the Judith River; minimal county-side zoning) does not maintain a comprehensive countywide zoning code. Judith Basin County operates under the Montana Subdivision and Platting Act (MCA Title 76 Ch. 3) and state building code (IRC 2018, administered by the Montana Department of Labor & Industry, Building Codes Bureau). Incorporated municipalities include Stanford (~410 residents, county seat) and Hobson (~190); both are subject to Montana SB 528 (2023, Mont. Code Ann. § 76-2-345) ADU preemption inside their town limits. SB 528 applies to ALL incorporated Montana cities (NOT population-gated per the Montana AG interpretation underlying the MT-CW2 finding). At the COUNTY tier, SB 528 is municipal-only and does NOT reach unincorporated county land. Census-designated places include Buffalo, Geyser, Moccasin, and Raynesford - all unincorporated rural prairie communities along US-87 and MT-200. The county's economic base is ranching (cow-calf, sheep), dryland wheat farming, and outfitter / hunting operations - elk hunting in the Highwood and Little Belt foothills draws sustained shoulder-season tourism.

State-floor overlay: Montana SB 528 establishes a state ADU floor for incorporated Montana cities; Stanford and Hobson are squarely subject inside their town limits. SB 528 does NOT extend to unincorporated Judith Basin County. ADU permissibility on unincorporated parcels is determined by state-level oversight only (no county zoning).

Judith Basin County's overlay landscape is light, reflecting the county's small population and prairie-dominated geography: (1) FEMA NFIP floodplain along the Judith River (the central county spine), Belt Creek, Wolf Creek, and Surprise Creek. (2) Wildland-Urban Interface in the Highwood Mountains (northwestern margin) and the Little Belt Mountains foothills (southern margin) - both BLM/USFS-administered with adjacent private inholdings. (3) Lewis & Clark National Historic Trail corridor along the Judith River - federal cultural-landscape recognition with no direct land-use authority but Section 106 review applies to federally-financed adjacent projects. (4) Square Butte and the Highwood Mountains scenic / volcanic geological overlay - BLM-managed with WSA-style sensitivity and adjacent ranchland. (5) Charles M. Russell Wildlife Refuge does NOT cover Judith Basin (it's in Phillips/Petroleum/Garfield counties downriver) but the broader CMR scenic-cultural corridor along the Missouri River breaks influences central-Montana tourism positioning.

• FEMA NFIP Special Flood Hazard Areas - Judith River, Belt Creek, Wolf Creek, Surprise Creek — Spring snowmelt and ice-jam events drive flooding peaks. The Judith River and Belt Creek corridors are sparsely developed with low-intensity ranchland - SFHA compliance burden is modest. ADU elevation cost where applicable runs $10,000-$25,000 (lower than higher-density Helena/Bozeman markets due to smaller foundation footprints).
• Wildland-Urban Interface - Highwood Mountains, Little Belt Mountains foothills, Lewis & Clark NF — Voluntary Firewise USA participation is light. Insurance markets are stable for prairie parcels and modestly tightening for foothill parcels. Most ranchland carries grass-fire risk rather than forest-fire risk; insurance pricing reflects this.
• Lewis & Clark National Historic Trail (Judith River corridor); scattered NRHP-listed ranch and mining structures — ADU work on NRHP-listed contributing properties triggers SHPO consultation only if federal financing or permitting (FHA, USDA RD) is involved. Yogo sapphires (the only sapphire deposit in the world that produces gem-quality untreated cornflower-blue sapphires) are mined adjacent to the southern county margin in the Little Belt Mountains; mining-claim adjacency considerations apply.
• Square Butte and Highwood Mountains scenic / volcanic geological overlay — Square Butte is one of the most recognized landmarks of central Montana. ADU positioning with view-of-Square-Butte amenities can command modest STR / scenic-rental premium. Federal inholdings near the Highwood / Little Belt boundaries can face Section 7 ESA consultation timelines for federally-financed projects.

Judith Basin County issues no countywide building permits for residential construction in unincorporated areas. Like most rural central Montana prairie counties without a full county building department, building-code enforcement is delegated to the State of Montana (Department of Labor & Industry, Building Codes Bureau) only for certain commercial or state-jurisdiction projects. Single-family residences and ADUs in unincorporated Judith Basin County are typically constructed without municipal-style plan review. State-level oversight applies to on-site septic (DEQ Subdivision review for parcels created after 1973) and well construction (DNRC water rights). Floodplain development requires a permit through the county floodplain administrator under MCA Title 76 Ch. 5 - applicable along the Judith River, Belt Creek, and other regulated waters. Stanford and Hobson operate their own town permitting processes inside their limits. Judith Basin County is in IECC climate zone 6B; valley-floor parcels (Stanford, Hobson, US-87 corridor) carry ground snow loads 30-50 psf; the Highwood Mountains and Little Belt Mountains foothills run 60-90+ psf. SB 528 is municipal-only at the county tier - it does NOT reach unincorporated county land.