Building permits, zoning and land rules in Washakie County, Wyoming

For an ordinary home in unincorporated Washakie County, the county does not require a building permit or contractor license¹. Wyoming State Fire Marshal plan review covers specified projects, including certain public buildings, assembly uses and fuel facilities⁸. Covered buildings undergo inspection for conformity with approved plans; newly constructed buildings in that regime require occupancy approval, subject to statutory exclusions and delegated local authority⁸. Wyoming has adopted statewide building, fire, fuel-gas, mechanical and existing-building codes, but applicability depends on the structure and use⁹. An owner may act as general contractor on a primary residence, subject to electrical licensing and applicable local or state approvals¹⁰.

For planning and septic questions in unincorporated Washakie County, contact the Washakie County Planner at 1001 Big Horn Avenue, Worland, WY 82401, or 307-347-6778^4,11. The Planner publishes the subdivision regulations and small-wastewater application materials^4,6,11. For a county-road driveway access application, contact Washakie County Road & Bridge at 601 15 Mile Road, Worland, WY 82401, or 307-347-4361¹². We could not confirm who issues building permits inside Worland or Ten Sleep; ask each town hall. Qualifying domestic septic systems in both stay under the county Planner's authority⁴.

Washakie County reports no countywide zoning¹. The county's subdivision regulations are separate from zoning, and the county does not administer city zoning¹³. Zoning does exist inside Worland, which maintains zoning districts and use classifications, and inside Ten Sleep, which publishes a Title 9 Development Code^2,3,13. Those rules stop at town limits. No county zoning rule sets minimum dwelling size or building height or restricts accessory dwellings or tiny-home occupancy in unincorporated Washakie County¹. Covered land divisions still require a subdivision permit unless exempt⁶. Sketch-plan and preliminary-plat materials generally must arrive at least 5 business days before a regular meeting; the Planning Commission acts on a complete sketch plan within 45 days⁶. Sketch-plan review costs $50, and preliminary-plat review costs $100 except for a simple subdivision⁶. The final plat is the permit application and requires full payment of accrued county notification fees, with no fixed notification amount stated⁶.

The Washakie County Planning Office authorizes domestic septic-tank and drainfield systems with flows below 2,000 gallons per day under delegated state authority⁴. Submit the application and wait for design approval before construction; a new residential septic permit costs $100 and renewal costs $50⁴. Site suitability is evaluated through photographs or a Planning Office inspection; schedule a requested visit at least 48 hours before excavation⁴. For a minor subdivision with at least 1.5 acres of developable land per lot, an exception concerns specified water-and-sewage reports and DEQ review, not individual septic construction authorization; the Commission may still require DEQ review, and at least one percolation test per two lots is required^4,6. Only 27.8% of mapped soils lack severe conventional drain-field limits, so evaluate the parcel early¹⁴. Systems outside county authority may require Wyoming DEQ permits⁴.

We could not confirm a rule resolving full-time RV occupancy on a standalone parcel in unincorporated Washakie County; ask the County Planner about the proposed use and wastewater arrangement¹¹. The rules we found cover commercial campgrounds open to the public, which need safe sewage, water supply and public-road access and go through the county subdivision process⁶. In such a campground, a tenant or camping unit staying beyond 90 consecutive days needs prior Planning Commission notification and approval, and a campground that breaks the limit may be required to apply as a mobile-home-park subdivision⁶. Tiny-home occupancy has no county zoning rule to run into on unincorporated land, though septic and driveway rules still apply¹. In a mobile-home-park subdivision, each lot must have at least 3,000 square feet, be at least 40 feet wide and hold only one mobile home⁶. Front and rear yards must be at least 15 feet and side yards at least 10 feet; the home and accessories may cover no more than 50 percent of the lot⁶.

1. Confirm jurisdiction: unincorporated Washakie County has no county zoning districts, while Worland sets city zoning; qualifying domestic septic systems remain with the county Planner^1,2,4.

1. If dividing land, start with the County Planner and sketch-plan process⁶.

1. For a subdivision proposing water or sewer service, document provider capacity and complete the required review⁶.

1. Obtain county authorization for a qualifying domestic septic system before construction⁴.

1. Obtain a State Engineer permit before constructing a groundwater well for beneficial use⁷.

1. Apply before constructing county-road access; subdivision lots also need public-road and fire access^5,6.

1. Ask whether State Fire Marshal inspection and occupancy approval apply to the proposed building⁸.

For a Washakie County subdivision lot, check that the final plat references recorded legal documents providing access to a public road; the county may require engineered road plans⁶. Each lot also needs fire access, and dead-end fire-access roads longer than 750 feet require local fire-chief approval⁶. A new county-road driveway requires an application and preliminary and final inspections⁵. Subdivision plats must identify flood hazards: affected lots may be developed only if hazards are eliminated or mitigated, and unmitigable areas must be placed in lots where development is prohibited⁶. A preliminary plat must also map floodplains and unsuitable soil within or next to the subdivision⁶. That review applies to subdivisions only; we could not confirm a separate countywide floodplain-development permit, so ask the County Planner^6,11. A beneficial-use well requires State Engineer approval before construction; monitoring wells used only for water-level measurement or sampling are exempt^7,15. Vacating an approved final plat costs $150 plus county notice costs⁶.