Marshall County, SD zoning map, flood zone and property lines by address
Free, no account. Or open the South Dakota map and tap a lot.
Towns in Marshall County: Britton.
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's countywide study for Marshall County has 38 FIRM panels, the newest effective December 2023; 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 Marshall 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 South Dakota county parcel layers (each county publishes its own), so a Marshall lot shows the same lines the county director of equalization draws. Marshall County covers about 536,374 acres of land and 30,809 acres of water.
Mapped lines are approximate. The Marshall County director of equalization keeps the parcel record (Marshall County website); a licensed surveyor sets the true corners.
Zoning
Marshall County zones its unincorporated land, and Britton zones the land inside its limits. ParcelSheet shows the use the county director of equalization 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 South Dakota's county planning and zoning law (South Dakota Codified Laws Chapter 11-2), local governments can allow an accessory dwelling unit on a lot with a house. Whether a Marshall 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. Marshall County is soil survey area SD091, Marshall County, South Dakota, last updated September 2026, on Web Soil Survey.
A new or changed septic system in Marshall County must follow the South Dakota Department of Agriculture and Natural Resources onsite rules, installed by a state certified installer; Marshall County may add its own permit.
Setbacks
Setbacks in Marshall 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 Britton for land inside its limits.
Hazards that apply
- Wetlands and wildfire. ParcelSheet shows the National Wetlands Inventory near a Marshall lot and the Forest Service wildfire hazard rating at it.
Questions
Is my house in a flood zone in Marshall County?
Type the address in the box above and ParcelSheet reads FEMA's flood zone at the lot's center. FEMA's countywide flood map for Marshall County has 38 panels, the newest effective December 2023. A lender or insurer uses the official FIRM panel; FEMA's Map Service Center has it.
How do I find property lines in Marshall County?
Open the South Dakota map, type the address, and the parcel outline from the Marshall County director of equalization 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 Marshall County?
Zoning in Marshall County is set by the county for unincorporated land and by each city (such as Britton) inside its own limits. ParcelSheet shows the use code the county director of equalization lists and links the office that sets the zoning; the planning office has the final word.
Can I build an ADU in Marshall County?
Under South Dakota's county planning and zoning law (South Dakota Codified Laws Chapter 11-2), counties and cities can allow an accessory dwelling unit, and each sets its own rules. In Marshall 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 Marshall County?
Yes. A new or changed septic system in Marshall County must follow the South Dakota Department of Agriculture and Natural Resources onsite rules, installed by a state certified installer; Marshall County may add its own permit. ParcelSheet shows the USDA soil survey's septic rating at the lot, from survey area SD091 (Marshall County, South Dakota).
What can I build on 5 acres in Marshall County?
Zoning in Marshall County is set by the county for unincorporated land and each city inside its own limits (such as Britton). 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 Marshall County website.
What are the residential setbacks in Marshall County (2026)?
Setbacks in Marshall 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 Marshall County website.
Next to Marshall County: Brown County, Day County, Roberts County.
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