Building permits, zoning and septic rules in Brookings County, South Dakota

At a glance

Building permit

Required for construction, movement or alteration of buildings in unincorporated Brookings County, subject to limited exemptions¹

Zoning

Yes; residential lot minimums include 35 acres in the Agricultural District and 20,000 square feet in the Lake Park District, subject to exceptions⁵⁶

Building codes

The county adopted the 2021 International Residential Code and International Building Code for covered projects⁷

Septic

South Dakota DANR sets minimum standards; state review is limited for a conventional individual residential system³⁸

RV living

A general private-land occupancy rule could not be confirmed; ask County Development about the parcel and district²

Manufactured home

A county building permit is required, and moved previously occupied homes face location, construction-date and neighbor-consent rules⁹

Owner-builder

Qualifying resident owners have an electrical-licensure exemption, but still need a homeowner permit and inspections¹⁰

Who to call

Contact details are copied from each office’s official page and were checked against it on October 7, 2026.

Do you need a building permit in Brookings County, South Dakota?

Yes. Unincorporated Brookings County requires a building permit to erect, move, structurally alter, use or construct a building or accessory building¹. A structure at or below 120 square feet is exempt, as are shingling, replacement siding, window replacement, exterior painting and interior improvements that do not move load-bearing walls¹. Covered projects must wait until the permit is issued and displayed¹. Brookings County has adopted the 2021 International Residential Code and the 2021 International Building Code for covered projects⁷. New and used manufactured or mobile homes also require county building permits¹¹. The state farmstead exclusion from South Dakota's default design standard does not waive Brookings County zoning, building permits or locally adopted requirements¹².

Who issues building permits in Brookings County, and how do you reach them?

The Brookings County Development Department is the first call for planning, zoning and building-permit questions on unincorporated land². Reach the department at 605-696-8350 or countydevelopment@brookingscountysd.gov, or visit 520 3rd St, Ste 110, Brookings, SD 57006². A building-permit application requires applicant and property details, structure dimensions, residential floor plans, approximate cost, road setback, water and sewer information, structural drawings and a Right to Farm Covenant for a new residence¹³. New residences and residential additions receive three onsite inspections before occupancy; garages and agricultural-building snow loads are inspected after completion¹⁴. The county charges $100 per building inspection, with the number set when the permit is issued¹⁵. State electrical and plumbing inspections are separate from county building inspections¹⁶¹⁷.

Does Brookings County have zoning for RVs, tiny homes and setbacks?

Yes. Brookings County divides its unincorporated land into zoning districts with different uses, setbacks and lot standards⁵¹⁸. Residential lots generally need 35 acres in the Agricultural District and 20,000 square feet in the Lake Park District, subject to ordinance exceptions⁶. An existing farmstead can qualify for a residence on less than 35 acres when it is separated from adjoining farmland and the parcel is already a lot of record or contains at least 5 acres¹⁹. The City of Brookings and county also share a joint-jurisdiction area, so confirm the controlling ordinance before relying on county standards²⁰. Brookings County regulates subdivisions and publishes preliminary and final plat checklists²¹. We could not confirm a general minimum dwelling floor area, accessory-dwelling rule or private-land RV rule; ask County Development about the parcel and intended use².

How do septic permits work in Brookings County?

South Dakota DANR sets the minimum onsite-wastewater requirements that apply in Brookings County, and local governments may adopt stricter standards³. Contact DANR before installing a new system unless it is a conventional onsite system serving an individual residence; other systems receiving human waste require plans and specifications submitted to DANR⁸. The DANR onsite-wastewater contact number is (605) 773-4647²². Lake Park District lots smaller than 20,000 square feet must connect to an approved sanitary sewer district or use a sealed holding tank; an existing septic tank and drain field on such a lot may not be replaced with another conventional system⁴. Only about 1.3% of Brookings County soils are rated without severe limitations for a conventional drain field, so evaluate the site before fixing the house plan and budget²³. We could not confirm a routine county septic inspection; ask DANR and County Development what applies to the site²²².

Can you live in an RV or tiny home on your land in Brookings County?

Brookings County has zoning across its unincorporated area, but we could not confirm a general rule allowing or prohibiting full-time RV living or temporary camping on private land⁵. Ask the Brookings County Development Department whether the district allows the proposed use and what setbacks or conditional approvals apply²¹⁸. We also could not confirm a tiny-home-specific occupancy rule; a tiny home regulated as a residence remains subject to the county building-permit process and applicable building code¹⁷. Manufactured, mobile and modular homes used as year-round dwellings require a county building permit, and previously occupied homes moved onto a site face construction-date and neighbor-consent conditions⁹. Where water or electricity is unavailable, state rules recognize specified unconventional sanitation systems, but most require state approval before installation²⁴. County campground and resort sanitation rules do not answer whether an RV can be occupied on an ordinary private parcel²⁵.

Building a home in Brookings County: the steps, in order

1. Confirm whether county, municipal or joint-jurisdiction zoning governs the parcel²⁰.
2. Ask County Development for the district, allowed use, lot-size rule, setbacks and any plat or special-use approval²⁶²¹.
3. Evaluate wastewater and well feasibility; DANR review depends on the septic design, and the proposed well use may require a state water-right permit⁸²⁶.
4. Check flood mapping and obtain a county floodplain development permit when the site is in a designated special flood-hazard area²⁷.
5. If the site is adjacent to a state highway, obtain the required state access permit before the county building or use permit²⁸.
6. Submit the building-permit application and wait for the issued permit before starting covered work¹¹³.
7. Schedule county building inspections and separate state electrical and plumbing inspections¹⁴¹⁶¹⁷.

What should you check before buying land in Brookings County?

Start with jurisdiction and zoning because incorporated places and the City of Brookings joint-jurisdiction area may use a different process from ordinary unincorporated land²⁰. Verify the district, allowed use and lot size with County Development; the Agricultural and Lake Park districts have materially different residential minimums⁶². If a seller proposes carving off an existing farmstead, confirm that the parcel and approval path satisfy the special farmstead exception instead of assuming every small agricultural parcel is buildable¹⁹. Review flood mapping because development in a designated special flood-hazard area requires county review²⁷. Test wastewater feasibility early because only about 1.3% of county soils are rated without severe limitations for conventional drain fields²³. Confirm legal access and any required plat before closing²¹²⁸. The median property-tax bill is about $2,795 per year, with an effective rate near 1.1%²⁹³⁰.

Watch-outs

• A Brookings County building permit can become void when substantial progress stalls, so ask County Development about the expiration and written-extension deadlines¹².
• Mobile and manufactured homes require a tie-down inspection within 30 days after being moved onto a site¹⁴.
• A parcel near a South Dakota state highway may need a state access permit before Brookings County can issue a building or use permit²⁸.

Sources

1. Complete Zoning Ordinance, quoted and re-checked
2. Brookings County Development Department (brookingscountysd.gov)
3. On-Site Wastewater Systems in South Dakota, quoted and re-checked
4. brookingscountysd.gov, quoted and re-checked
5. Planning & Zoning, quoted and re-checked
6. Complete Zoning Ordinance, quoted and re-checked
7. Permit Applications Information Booklet, quoted and re-checked
8. On-Site Wastewater Systems in South Dakota, quoted and re-checked
9. Brookings County Ordinance No. 2024-01 Zoning Ordinance, quoted and re-checked
10. South Dakota Electrical Commission - Homeowner Wiring (South Dakota statewide rule), quoted and re-checked
11. Permit Applications Information Booklet, quoted and re-checked
12. South Dakota Codified Law Chapter 11-10: Building Codes and Standards (South Dakota statewide rule), quoted and re-checked
13. Permit Applications Information Booklet, quoted and re-checked
14. Permit Applications Information Booklet, quoted and re-checked
15. Permit Applications Information Booklet, quoted and re-checked
16. South Dakota Electrical Commission - Homeowner Wiring (South Dakota statewide rule), quoted and re-checked
17. South Dakota Plumbing Commission - Inspections (South Dakota statewide rule), quoted and re-checked
18. Planning & Zoning Ordinances & Forms, quoted and re-checked
19. Brookings County Ordinance No. 2024-01 Zoning Ordinance, quoted and re-checked
20. Planning & Zoning, quoted and re-checked
21. Planning & Zoning Ordinances & Forms, quoted and re-checked
22. South Dakota Department of Agriculture and Natural Resources (danr.sd.gov)
23. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
24. Administrative Rule 74:53:01 — Individual and Small On-Site Wastewater Systems (South Dakota statewide rule), quoted and re-checked
25. brookingscountysd.gov, quoted and re-checked
26. South Dakota Water Rights — Drilling a Well (South Dakota statewide rule), quoted and re-checked
27. Brookings County Floodplain Development Permit, quoted and re-checked
28. brookingscountysd.gov, quoted and re-checked
29. Median property tax bill: Bolthole Index county data
30. Effective property tax rate: Bolthole Index county data

Written October 7, 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.