Unincorporated Power County, Idaho requires a permit before construction, site preparation, alterations, demolition, occupancy and other covered work begins1. Power County also has zoning and subdivision ordinances administered by its Building Administrator / Planning and Zoning Department23. Septic permits and site evaluations go through Southeastern Idaho Public Health45.
At a glance
- Building permit
- Required before construction, site preparation and other covered work in unincorporated Power County1
- Zoning
- Yes; district-specific rules and setbacks apply26
- Septic permits
- Southeastern Idaho Public Health handles applications and site evaluations45
- Agricultural buildings
- A limited exemption applies on qualifying agricultural land, but a development permit and inspections still apply7
- RV or tiny-home living
- Not confirmed for private land; ask county Planning and Zoning before relying on either use2
- Owner-builder exemption
- Not confirmed; ask the county Building Administrator before starting work8
- Private wells
- An Idaho Department of Water Resources drilling permit is required before drilling9
Who to call
Building permits
Power County Building Administrator / Planning and Zoning
Building permits, inspections, zoning, subdivision and land-use questions in Power County
73 Fort Hall Ave. Ste. A American Falls, ID 83211
Septic permits
Southeastern Idaho Public Health, Power County Office
Septic applications, site evaluations and onsite-system permitting for Power County
590 1/2 Gifford, American Falls, ID 83211
Contact details are copied from each office’s official page and were checked against it on September 27, 2026.
Do you need a building permit in Power County, Idaho?
Yes. Unincorporated Power County requires a permit before site preparation, construction, enlargement, alteration, repair, moving, removal, demolition, conversion, occupancy, equipment use or placement of an agricultural building begins1. The county has adopted the 2018 editions of the International Building Code, International Residential Code, International Energy Conservation Code, International Fire Code and International Existing Building Code, subject to county amendments10. Separate Idaho permits are required when electrical, plumbing or HVAC work is performed under the state-administered program11. Power County may charge a plan-review fee of up to 65 percent of the building-permit fee for new buildings, additions and remodels12. Construction under a county permit has six listed inspection stages, and each must be completed before the next construction step begins13. A regulated building or structure also needs a certificate of occupancy before use or occupancy14.
Who handles Power County building permits, and how do you reach them?
Power County Building Administrator / Planning and Zoning is the combined office for building-permit and county land-use questions15. The office is at 73 Fort Hall Ave. Ste. A, American Falls, ID 83211, and its phone number is 208-226-762515. The county directs applicants to submit a complete set of blueprints to the Building Administrator 10 to 14 days before building; larger commercial and residential projects require the original stamp of an engineer or architect16. The office page warns that some form links are down because of ordinance changes, so calling for the currently required documents is sensible15. Power County’s published fee rules are valuation-based, and plan review for a new building, addition or remodel can add up to 65 percent of the building-permit fee12. The reviewed sources do not establish a general owner-builder exemption, so an owner planning to perform the work should ask this office what licensing, permit and inspection requirements apply8.
Does Power County have zoning?
Yes. Power County has zoning districts, including agricultural districts, with district-specific setbacks administered by the county’s Planning and Zoning function2. The county code contains both zoning and subdivision ordinances, and the comprehensive plan says its land-use categories are generally consistent with existing zoning districts36. Published setbacks vary by road and use: a dwelling is set back 50 feet from an arterial road, 35 feet from another road, and 10 feet from side and rear property lines in an AG or RR zone17. Those figures do not answer every parcel question, because the applicable zoning district and roadway control the result17. Power County’s reviewed sources do not confirm a universal minimum lot size, minimum dwelling size, lot-coverage limit or building-height limit. Ask Building Administrator / Planning and Zoning to identify the parcel’s district and applicable dimensional rules before buying or laying out a structure152.
How do septic permits work in Power County?
Southeastern Idaho Public Health administers onsite septic rules and permits for Power County418. Its Power County office is at 590 1/2 Gifford, American Falls, ID 83211, phone (208) 226-509619. An application requires a complete signed form, a warranty deed or tax notice, a scaled plot plan and an onsite evaluation; the applicant supplies test holes 8 to 10 feet deep depending on soil type5. The district lists $300 for a speculative site evaluation and $925 for a full site evaluation and permit if the site is suitable, while noting that fees can change5. Only 35.4 percent of county soils are rated without severe limits for a conventional septic drain field, so confirm suitability before committing to a house location20. A system cannot receive wastewater until the required final installation inspection occurs21. The district may deny an onsite permit where public or central wastewater treatment is reasonably accessible22.
Can you live in an RV or tiny home on land in Power County?
Power County’s reviewed rules do not confirm whether long-term RV occupancy or temporary camping is allowed on private land in unincorporated Power County. The reviewed rules also do not establish a specific tiny-home occupancy rule or a universal minimum dwelling size. Because Power County has district-specific zoning and setbacks, ask Building Administrator / Planning and Zoning about the parcel’s zone, proposed use, utilities and occupancy before buying or moving an RV or tiny home onto the site215. Do not use Idaho’s camping limits for Fish and Game lands as an answer for private property: that rule applies to Wildlife Management Areas and separate access sites, not privately owned land23. A manufactured home is clearer procedurally: Power County lists placement of a manufactured home among work needing a building permit, while Idaho requires inspection and approval of every manufactured-home installation before occupancy1524.
Building a home in Power County: the steps, in order
- Ask Power County Building Administrator / Planning and Zoning to confirm the zoning district, setbacks, subdivision restrictions and current application forms153.
- Arrange the septic application and site evaluation with Southeastern Idaho Public Health, using a scaled plot plan and applicant-provided test holes5.
- Obtain approval for the travel way from Power County Highway District personnel before the county can issue a permit for a new dwelling25. A driveway connecting to a state highway separately needs an Idaho Transportation Department encroachment permit26.
- If a private well is planned, obtain an Idaho Department of Water Resources drilling permit before drilling and use a state-licensed well driller9.
What should you check before buying land in Power County?
Start with septic feasibility: only 35.4 percent of Power County soils are rated without severe limitations for a conventional drain field, and the health district requires an onsite evaluation for an application205. Check terrain as well, because 60.8 percent of county land has a slope of 15 percent or less, while a specific parcel may be much steeper27. Confirm legal access and driveway approval; a new dwelling cannot receive its building permit until Power County Highway District personnel approve the travel way25. For mapped special flood-hazard areas, Power County requires a development permit before construction or development begins28. Water planning matters in a county averaging 16.1 inches of precipitation annually, and a new well needs an Idaho Department of Water Resources drilling permit before work starts299. For a rough carrying-cost benchmark, the effective property-tax rate is about 0.8 percent and the median annual property-tax bill is about $1,5773031.
Watch-outs
- Power County does not issue a new-dwelling building permit until Power County Highway District personnel approve the travel way to the dwelling25.
- Only 35.4 percent of Power County soils are rated without severe limitations for a conventional septic drain field, so obtain a site evaluation before fixing the house location20.
- The reviewed rules do not confirm long-term RV occupancy, temporary private-land camping or tiny-home occupancy; ask Power County Building Administrator / Planning and Zoning before relying on any of those uses152.
- A qualifying agricultural-building exemption still leaves the project subject to a development permit, building inspections and possible zoning or administrative fees7.
Sources
- 8-1-4: Permits Required, quoted and re-checked
- Power County — Building Administrator / Planning & Zoning (2026 county census)
- Building Administrator / Planning and Zoning, quoted and re-checked
- Southeastern Idaho Public Health — Septic Permits (2026 county census)
- Septic Permits, quoted and re-checked
- Building Administrator / Planning and Zoning, quoted and re-checked
- 8-1-12: Exemptions, quoted and re-checked
- (2026 county census)
- Wells Overview (Idaho statewide rule), quoted and re-checked
- 8-1-13: Adoption of Codes, quoted and re-checked
- Frequently Asked Questions (FAQs) - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
- 8-1-8: Fees, quoted and re-checked
- Six Required Inspections – Reminder to Contractors, quoted and re-checked
- 8-1-13-1: International Building Code Amendments, quoted and re-checked
- Power County Building Administrator / Planning and Zoning (powercounty.gov)
- Basic Requirements for Building Permits, quoted and re-checked
- Basic Requirements for Building Permits, quoted and re-checked
- Septic and Septage (Idaho statewide rule), quoted and re-checked
- Southeastern Idaho Public Health, Power County Office (siphidaho.org)
- Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
- IDAPA 58.01.03 Individual/Subsurface Sewage Disposal Rules (Idaho statewide rule), quoted and re-checked
- IDAPA 58.01.03 Individual/Subsurface Sewage Disposal Rules (Idaho statewide rule), quoted and re-checked
- Public Use of Department Lands and Access Areas (Idaho statewide rule), quoted and re-checked
- Building Archives - Division of Occupational and Professional Licenses (Idaho statewide rule), quoted and re-checked
- 8-1-11: Driveway Requirements, quoted and re-checked
- Types of Right-of-Way Encroachment Permits (Idaho statewide rule), quoted and re-checked
- Share of land at 15% slope or less: Bolthole Index county data
- 9-1-4: Development Permit Required, quoted and re-checked
- Annual precipitation: Bolthole Index county data
- Effective property tax rate: Bolthole Index county data
- Median property tax bill: Bolthole Index county data
Written September 27, 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.