Johnson County, WY zoning map, flood zone and property lines by address
Free, no account. Or open the Wyoming map and tap a lot.
Towns in Johnson County: Buffalo.
Flood zone by address
ParcelSheet reads FEMA's National Flood Hazard Layer at the lot: the zone, whether it is a high risk area where lenders ask for flood insurance, and the base flood elevation where FEMA lists one. FEMA has 46 FIRM panels covering Johnson County, the newest effective May 2015; no coastal V zones are mapped in it.
The official panel and any Letter of Map Amendment are at FEMA's Map Service Center. An elevation certificate for a Johnson house comes from a licensed surveyor and is often on file with the county or city building office.
Property lines
The parcel outline, parcel number and mapped size come from the Wyoming statewide parcels (2026 tax year), from county assessors, so a Johnson lot shows the same lines the county assessor draws. Johnson County covers about 2,658,657 acres of land and 13,085 acres of water.
Mapped lines are approximate. The Johnson County assessor keeps the parcel record (Johnson County website); a licensed surveyor sets the true corners.
Zoning
Johnson County zones its unincorporated land, and Buffalo zones the land inside its limits. ParcelSheet shows the use the county assessor lists for the lot and links the county planning and zoning office for the district, the uses it allows and the lot size it needs.
ADU and guest houses
Under Wyoming's county planning and zoning law (Wyoming Statutes 18-5-201 through 18-5-208), local governments can allow an accessory dwelling unit on a lot with a house. Whether a Johnson lot can add one depends on its district; the county planning and zoning office has the rule. ParcelSheet shows the mapped lot size and the ground's slope, the first two things the question turns on.
Septic and soil
ParcelSheet reads the USDA soil survey at the lot: the soil's name, its septic absorption rating and whether it is prime farmland. Johnson County is soil survey area WY619, Johnson County, Wyoming, Southern Part, last updated September 2026, on Web Soil Survey.
A new or changed septic system in Johnson County needs a permit from the Johnson County small wastewater permitting authority (the county, or Wyoming DEQ in counties without a delegated program).
Setbacks
Setbacks in Johnson County come from the zoning district: the front, side and rear distances a house must keep. ParcelSheet does not draw setback lines; the county zoning office gives them for the lot's district, and Buffalo for land inside its limits.
Hazards that apply
- Wetlands and wildfire. ParcelSheet shows the National Wetlands Inventory near a Johnson lot and the Forest Service wildfire hazard rating at it.
Questions
Is my house in a flood zone in Johnson County?
Type the address in the box above and ParcelSheet reads FEMA's flood zone at the lot's center. FEMA has 46 flood map panels covering Johnson County, the newest effective May 2015. A lender or insurer uses the official FIRM panel; FEMA's Map Service Center has it.
How do I find property lines in Johnson County?
Open the Wyoming map, type the address, and the parcel outline from the Johnson County assessor shows on the map with its parcel number and mapped size. Mapped lines are approximate; only a licensed surveyor sets the true corners.
What is my property zoned in Johnson County?
Zoning in Johnson County is set by the county for unincorporated land and by each city (such as Buffalo) inside its own limits. ParcelSheet shows the use code the county assessor lists and links the office that sets the zoning; the planning office has the final word.
Can I build an ADU in Johnson County?
Under Wyoming's county planning and zoning law (Wyoming Statutes 18-5-201 through 18-5-208), counties and cities can allow an accessory dwelling unit, and each sets its own rules. In Johnson County ask the zoning office for the lot's district first; ParcelSheet shows the lot size as mapped so you can see the room you have.
Do I need a septic permit in Johnson County?
Yes. A new or changed septic system in Johnson County needs a permit from the Johnson County small wastewater permitting authority (the county, or Wyoming DEQ in counties without a delegated program). ParcelSheet shows the USDA soil survey's septic rating at the lot, from survey area WY619 (Johnson County, Wyoming, Southern Part).
What can I build on 5 acres in Johnson County?
Zoning in Johnson County is set by the county for unincorporated land and each city inside its own limits (such as Buffalo). The zoning district decides the uses, how many homes and the smallest lot it allows on 5 acres. ParcelSheet shows the lot size as mapped and the use code on the parcel record; the planning office has the district and its rules. See the Johnson County website.
What are the residential setbacks in Johnson County (2026)?
Setbacks in Johnson County come from the zoning code of the county, or of the city when the lot is inside city limits: the front, side and rear distances depend on the lot's district. ParcelSheet does not draw setback lines or give a number it did not read; the zoning office gives them for the district. See the Johnson County website.
Next to Johnson County: Big Horn County, Campbell County, Natrona County, Sheridan County, Washakie County.
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