Sioux County, North Dakota has no county building-permit or zoning office: the state's official county officials directory lists neither, and North Dakota's new statewide building code is enforced only by counties, cities, or townships that choose to adopt it123. That's a gap in the directory, not a confirmed 'no zoning ever' answer: North Dakota law lets a county's board of commissioners zone the whole county, and this guide could not confirm whether Sioux County has4. Septic (onsite wastewater) is different and confirmed: Western Plains Public Health issues the local installation permit Sioux County requires before work begins5.
At a glance
- Building permit
- Not found; no county building department is listed1
- County zoning
- Not confirmed either way; North Dakota lets counties zone countywide, but no Sioux County ordinance was located24
- Septic permit
- Required; Western Plains Public Health issues the local permit before work begins56
- Owner-builder exemption
- Not confirmed for Sioux County7
- Well permit
- Only needed above 12.5 acre-feet/year; typical domestic wells don't need one8
- Floodplain development
- Requires a local permit before work begins in a Special Flood Hazard Area9
- Driveway onto a state highway
- Needs an NDDOT driveway permit (Form SFN 5918)10
Who to call
Also useful
General county administration and support for the Board of County Commissioners, which holds North Dakota's statutory authority to regulate subdivision and, if the county chooses, zoning; the practical starting point for building-permit or land-use questions since no dedicated department was found
PO Box L, Fort Yates, ND 58538-0529
Septic permits
Issues the local onsite wastewater (septic) system permit required before installation begins in Sioux County, alongside the installer's separate state DEQ license
403 Burlington St SE, Mandan, ND 58554
Floodplain permits
Sioux County Floodplain Administrator (Emergency Manager's office)
Issues the floodplain development permit required before any work in a Special Flood Hazard Area; the state's official administrator list names this role jointly with the Emergency Manager/Sheriff position
PO Box L, Fort Yates, ND 58538-0529
Roads & driveways
Sioux County Highway Department
Maintains Sioux County roads; a driveway onto a state highway instead needs a separate NDDOT permit
9502 26th Ave, Selfridge, ND 58568-9543
Contact details are copied from each office’s official page and were checked against it on September 29, 2026.
Do you need a building permit in Sioux County, North Dakota?
No county building-permit department was found for Sioux County: the state's official county officials directory lists no building or permit office, consistent with a county that hasn't set up a permitting program1. North Dakota has adopted a new statewide building code, based on the 2024-cycle IBC, IRC, IMC, and IFGC, effective in 2026, but Commerce doesn't enforce it: only a city, township, or county that elects to adopt and enforce the code does so, and no official source confirms Sioux County has made that election311. A factory-built modular home is different: a manufacturer producing two or more modular homes a year must use a certified third-party inspector during manufacturing, regardless of local enforcement12.
Who handles permits and land-use questions in Sioux County?
There's no dedicated building or planning department in Sioux County; day-to-day county administration runs through the Auditor's Office, which also supports the Board of County Commissioners13. Septic (onsite wastewater) permits go through Western Plains Public Health, the multi-county health district that serves Sioux County14. Floodplain development permits go through the county's Floodplain Administrator, a role the state pairs with the Emergency Manager's office15. Road and highway matters go through the Sioux County Highway Department16.
Does Sioux County have zoning?
Not confirmed either way. The state's official county officials directory lists no Sioux County planning or zoning office, which points toward no zoning ordinance, but it isn't proof: North Dakota law lets a county's board of commissioners zone the whole county, including unincorporated land, and we could not confirm whether Sioux County has used that authority24. North Dakota also lets county commissioners adopt subdivision regulations requiring plat approval, reasonable fees, and public improvements, but we could not confirm that Sioux County has adopted such a resolution17. Because neither ordinance was confirmed, ask the Auditor's Office about minimum home size, lot size, setbacks, RVs, tiny homes, manufactured homes, and plat approval before relying on a parcel's apparent lack of restrictions13. State law protects farming and normal incidents of farming from restrictions adopted under the county subdivision chapter, but that protection does not establish an exemption from other requirements18.
How do septic permits work in Sioux County?
Septic (onsite wastewater) systems in Sioux County involve both state and local authority: the North Dakota Department of Environmental Quality licenses installers and administers statewide permitting and inspection rules, while Western Plains Public Health requires the local installation permit before work begins196. Western Plains Public Health serves Sioux County as the local public-health authority for this program20. Only about 12.5% of Sioux County's soils are rated free of severe limits for a conventional septic drain field, so budget for a site evaluation and possibly an engineered system21.
Can you live in an RV or tiny home on your land in Sioux County?
This guide could not confirm a Sioux County rule addressing RV, tiny-home, or manufactured-home occupancy on private land: no zoning ordinance was located, and North Dakota's state-park camping limit of 14 nights in any 30-day period applies to state park campsites, not your own land222. A manufactured home is different in one respect regardless of local zoning: any new manufactured home installed in North Dakota for residential use must be set up by a Division of Community Services-licensed installer and pass a state-licensed inspection, with at least two inspections for a double-wide and one for a single-wide23. Call the Auditor's Office before you commit to living in an RV or tiny home on a Sioux County parcel, since no confirmed county rule settles the question yet13.
Building a home in Sioux County: the steps, in order
- Confirm with the Auditor's Office whether your tract is inside any city limits or a city's extraterritorial zoning jurisdiction, since Sioux County's own zoning status wasn't confirmed either way132.
- No county building permit was found to be required in Sioux County, though North Dakota's new statewide building code, effective in 2026, still sets a construction standard where a local jurisdiction chooses to enforce it13.
- Line up your septic (onsite wastewater) permit: apply to Western Plains Public Health for the local permit, and confirm your installer holds a state DEQ license, before work begins146.
- If your well will draw more than 12.5 acre-feet a year, apply to the North Dakota Department of Water Resources for a water-appropriation permit; typical domestic wells below that threshold don't need one8.
- If any part of your build sits in a Special Flood Hazard Area, get a floodplain development permit from the county's Floodplain Administrator before work begins; floodway proposals also require notice to and review by the Department of Water Resources unless an exemption applies1524.
- If your driveway connects to a state highway, apply for an NDDOT driveway permit, Form SFN 5918, and don't finish the approach until NDDOT checks and approves it10.
- Reach the Sioux County Highway Department for anything involving county road maintenance16.
What to check before you buy land in Sioux County
Soils: only about 12.5% of Sioux County's soils are rated free of severe limits for a conventional septic drain field, so a site evaluation before you buy is worth the cost21. Flooding: development in a Special Flood Hazard Area needs a local permit before work begins24. A project in the regulatory floodway may not increase flood levels during the base flood discharge25. In the flood fringe, a home's lowest floor, including its basement, generally must be at least 1 foot above base flood elevation; a nonresidential building must meet that elevation standard or be floodproofed at least 2 feet above base flood elevation26. Water: a well drawing more than 12.5 acre-feet a year needs a state water-appropriation permit; a typical domestic well does not8. Taxes: the effective property tax rate is about 0.5%, with a median annual bill near $4102728.
Watch-outs
- Sioux County's zoning status is unconfirmed, not confirmed absent: North Dakota law lets counties zone countywide, so don't assume anything about your land's RV, tiny-home, or setback rules without calling the Auditor's Office first413.
- The state's official floodplain-administrator list for Sioux County may be out of date compared to the county's current staff directory; confirm who currently holds that role before you rely on an old name9.
- Sioux County has not published an owner-builder exemption, and no county building-permit program was found to exempt yourself from in the first place7.
Sources
- North Dakota Association of Counties - Sioux County Officials Directory (2026 county census)
- North Dakota Association of Counties - Sioux County Officials Directory (2026 county census)
- Building Codes | Commerce | North Dakota (North Dakota statewide rule), quoted and re-checked
- North Dakota Century Code, Chapter 11-33, County Zoning (North Dakota statewide rule), quoted and re-checked
- North Dakota DEQ - Septic Systems Program (2026 county census)
- On-Site Wastewater Treatment Systems (North Dakota statewide rule), quoted and re-checked
- (2026 county census)
- Private Well Owner’s Guide: Well Installation, quoted and re-checked
- Floodplain Management, quoted and re-checked
- SFN 5918 Driveway Application & Permit, quoted and re-checked
- Building Codes (North Dakota statewide rule), quoted and re-checked
- 2026 North Dakota State Building Code Book (North Dakota statewide rule), quoted and re-checked
- Sioux County Auditor's Office (ndaco.org)
- Western Plains Public Health (westernplainsph.org)
- Sioux County Floodplain Administrator (Emergency Manager's office) (ndaco.org)
- Sioux County Highway Department (ndaco.org)
- North Dakota Century Code Chapter 11-33.2 — Subdivision Regulation, quoted and re-checked
- North Dakota Century Code Chapter 11-33.2 — Subdivision Regulation, quoted and re-checked
- On-Site Wastewater Treatment Systems, quoted and re-checked
- Onsite Septic System Program, quoted and re-checked
- Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
- Parks and Recreation FAQ (North Dakota statewide rule), quoted and re-checked
- Manufactured Home Installation Program (North Dakota statewide rule), quoted and re-checked
- Floodplain Management, quoted and re-checked
- North Dakota Century Code Chapter 61-16.2, Floodplain Management, quoted and re-checked
- North Dakota Century Code Chapter 61-16.2, Floodplain Management, quoted and re-checked
- Effective property tax rate: Bolthole Index county data
- Median property tax bill: Bolthole Index county data
Written September 29, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.