Harper County, OK zoning map, flood zone and property lines by address
Free, no account. Or open the Oklahoma map and tap a lot.
Towns in Harper County: Laverne, 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 5 FIRM panels covering Harper County, the newest effective January 2012; 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 Harper 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 Oklahoma county parcel layers (each county publishes its own), so a Harper lot shows the same lines the county assessor draws. Harper County covers about 664,694 acres of land and 1,300 acres of water.
Mapped lines are approximate. The Harper County assessor keeps the parcel record; a licensed surveyor sets the true corners.
Zoning
Harper County zones its unincorporated land, and Laverne, Buffalo each zone the land inside their limits. ParcelSheet shows the use the county assessor lists for the lot and links the county planning commission or the city planning office for the district, the uses it allows and the lot size it needs.
ADU and guest houses
Under Oklahoma's county planning and zoning laws (Oklahoma Statutes Title 19, sections 865.51 and following), local governments can allow an accessory dwelling unit on a lot with a house. Whether a Harper lot can add one depends on its district; the county planning commission or the city planning 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. Harper County is soil survey area OK059, Harper County, Oklahoma, last updated August 2026, on Web Soil Survey.
A new or changed septic system in Harper County needs an Authorization to Construct from the Oklahoma Department of Environmental Quality, through the local DEQ environmental specialist for Harper County.
Setbacks
Setbacks in Harper 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 Laverne and Buffalo for land inside their limits.
Hazards that apply
- Wetlands and wildfire. ParcelSheet shows the National Wetlands Inventory near a Harper lot and the Forest Service wildfire hazard rating at it.
Questions
Is my house in a flood zone in Harper County?
Type the address in the box above and ParcelSheet reads FEMA's flood zone at the lot's center. FEMA has 5 flood map panels covering Harper County, the newest effective January 2012. A lender or insurer uses the official FIRM panel; FEMA's Map Service Center has it.
How do I find property lines in Harper County?
Open the Oklahoma map, type the address, and the parcel outline from the Harper 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 Harper County?
Zoning in Harper County is set by the county for unincorporated land and by each city (such as Laverne, 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 Harper County?
Under Oklahoma's county planning and zoning laws (Oklahoma Statutes Title 19, sections 865.51 and following), counties and cities can allow an accessory dwelling unit, and each sets its own rules. In Harper 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 Harper County?
Yes. A new or changed septic system in Harper County needs an Authorization to Construct from the Oklahoma Department of Environmental Quality, through the local DEQ environmental specialist for Harper County. ParcelSheet shows the USDA soil survey's septic rating at the lot, from survey area OK059 (Harper County, Oklahoma).
What can I build on 5 acres in Harper County?
Zoning in Harper County is set by the county for unincorporated land and each city inside its own limits (such as Laverne, 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.
What are the residential setbacks in Harper County (2026)?
Setbacks in Harper 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.
Next to Harper County: Beaver County, Ellis County, Woods County, Woodward County.
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