Unincorporated Monona County, Iowa requires an approved construction permit before new construction, an addition or moving a building onto a property.1 County zoning covers unincorporated land except specified federal, state and tribal land, while Environmental Health & Zoning handles private septic permits countywide.23
At a glance
- Building permit
- Required for new construction, additions and moving a building onto property in unincorporated areas1
- Zoning
- County zoning applies to unincorporated land; front yards run 35 to 100 feet by district24
- Septic
- County permit required; private systems may serve subdivisions where public sewer is not reasonably available56
- RV or tiny home
- Occupancy rules were not confirmed; ask Environmental Health & Zoning before relying on either as housing7
- Owner-builder
- Own-property work is exempt from state contractor registration, not the county permit requirement81
- Private well
- County permit required, including inside city limits; published fee is $150 and subject to change9
- Floodplain
- A separate permit is required before development in a county floodplain district10
Who to call
Building permits
Monona County Environmental Health & Zoning
Construction permits, zoning, floodplain permits, private wells and geothermal permits
610 Iowa Ave. Onawa, IA 51040
Septic permits
Monona County Environmental Health & Zoning
Permits for new septic systems and renovation of soil-treatment systems
610 Iowa Ave. Onawa, IA 51040
Contact details are copied from each office’s official page and were checked against it on October 10, 2026.
Off-grid gear
Going off-grid in Monona County means bringing your own water and power. The kit we’d start with:
- Water Crystal Quest Filter any source — well, rain, or creek — to drinking-clean.
- Power Bluetti Solar generators and home battery backup for living off the grid.
- Septic Soil percolation test kit Run your own perc test before paying an engineer — the first thing a septic office asks about.
- Water Well water test kit Bacteria, nitrates, hardness — know what the well on a parcel is really pumping.
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Do you need a building permit in Monona County, Iowa?
Yes. Unincorporated Monona County requires a building construction permit for new construction, additions and moving a building onto a property, and work may not start until the application is approved.1 A non-farm principal-structure permit costs $100, while qualifying farm construction on at least 40 acres is fee-exempt.1 Fees are published but subject to change.11 The county requires a buildable-parcel designation and Chapter 100 compliance before issuing the permit.1 Applications use county forms and duplicate plans showing lot dimensions, building location, size, height and intended use.12 The county's adoption of a general building code and its ordinary inspection requirements could not be confirmed; ask Environmental Health & Zoning what reviews and closeout steps apply.7
Building your own home does not remove the county permit: Iowa's exemption for people working on their own property applies to state contractor registration only, and it does not waive Monona County's construction-permit, zoning, septic or floodplain requirements.8
Who handles Monona County building permits, and how do you reach them?
Monona County Environmental Health & Zoning is the practical first stop for construction permits, zoning, private wells, septic systems and floodplain questions.7 The office is on the second floor of the courthouse at 610 Iowa Ave., Onawa, IA 51040, and its main phone number is 712-433-3400.7 The county's Common Forms page publishes construction-permit materials along with variance, special-use, rezoning, subdivision, septic and floodplain forms.7 Use that forms page to begin, then confirm the current fee because the published schedule is subject to change.11 For an entrance onto an Iowa primary highway, the Iowa Department of Transportation district office administers the access-permit process and must approve the application before work begins.13
Does Monona County have zoning?
Yes. Monona County zoning applies throughout unincorporated territory except land owned by the federal government, State of Iowa or Omaha Tribe of Nebraska; incorporated municipalities may administer their own land-use rules.14 The county publishes 10 base districts plus 3 overlays, including floodplain, airport and Loess Hills overlays, and structure-height limits vary by district.1516 Minimum front-yard setbacks are 75 feet in the A-1, A-2 and R-1 districts, 35 feet in R-2, 50 feet in R-3, R-4, C-1 and C-2, 75 feet in M-1 and 100 feet in M-2, measured from the right-of-way line, and a new dwelling next to hazardous-material storage must sit at least 500 feet from any property line.4 Ask Environmental Health & Zoning to confirm the parcel's district, allowed use, height limit and any variance or special-use process before fixing a house location.7 Iowa generally keeps qualifying agricultural land and structures primarily adapted to agricultural purposes outside county zoning while they remain in that use, but floodplain regulation may still apply.17 Monona County requires approval before covered development in a floodplain district.10
How do septic permits work in Monona County?
Monona County Environmental Health & Zoning requires a permit for a new septic system or renovation of the soil-treatment portion of an existing system; a percolation test may be required.5 The published fee is $150 for a new onsite wastewater permit and $75 for a repair permit, with a $100 penalty for installation without a permit.5 In a subdivision where public sewer is not reasonably available, private sewer or septic facilities may be allowed if they meet County Board of Health requirements.6 Contact the department before fixing the house location: only about 30.7% of mapped county soils are rated without severe limitations for a conventional drain field.18 A qualifying ownership transfer of a building served by a private sewage system requires a certified inspection before transfer, subject to statutory exceptions.19
Can you live in an RV or tiny home on your land in Monona County?
Monona County's rule for living in an RV on private land could not be confirmed, and neither could a general temporary-camping rule. Ask Environmental Health & Zoning about the parcel's zoning district, occupancy duration and sanitation before buying land for RV living.27 A county-specific tiny-home occupancy rule and a general minimum dwelling size also could not be confirmed.2 Iowa provides a clearer rule for a manufactured home: a county cannot reject a proposed residence solely because it is manufactured, but the home remains subject to the permanent-foundation, setback and minimum-square-footage standards applied to a site-built single-family dwelling on the same lot.20 An off-grid wastewater plan is not permit-free: a new private septic system requires county approval.65
Building a home in Monona County: the steps, in order
- Ask Environmental Health & Zoning to identify the zoning district, allowed use, height limit and buildable-parcel requirements.161
- If the parcel is being split, submit a division-of-land request; the Zoning Administrator provides the required method and procedures within 10 working days.2112
- Check for a floodplain district because covered development needs a separate permit.10
- Plan the private well and septic system before fixing the house location; both require county permits.95
- Submit the construction application, duplicate site plans and current fee, then wait for approval before work starts.121
- Ask which inspections and occupancy documents apply because a general county rule could not be confirmed.7
What should you check before buying land in Monona County?
Confirm the zoning district, allowed use, setbacks, height limit and buildable-parcel status with Environmental Health & Zoning before relying on a listing description.15161 Ask whether a recent parcel split complied with the county subdivision ordinance; divisions into 3 or more lots generally require a subdivision plat.21 For a subdivision lot, confirm whether sanitary sewer connection is required or whether an approved private system is available.22 Screen the site for floodplain limits and investigate soils early: about 30.7% of mapped soils lack severe limitations for a conventional drain field.1018 Confirm road access with the proper authority; an entrance onto a state primary highway goes through an Iowa Department of Transportation district office.13
Watch-outs
- Do not begin covered construction in unincorporated Monona County until the construction-permit application is approved.1
- A farm fee exemption does not erase floodplain review; Monona County's floodplain permit applies to covered development in a floodplain district.110
- Monona County's RV-living, temporary-camping, tiny-home and minimum-dwelling-size rules could not be confirmed; get a parcel-specific answer from Environmental Health & Zoning before buying for one of those uses.7
- Monona County's setbacks depend on the zoning district and are larger next to livestock feeding operations, grain bins and rivers, so get the district and setbacks confirmed in writing before siting a house.4
Sources
- Common Forms - Environmental Health/Zoning - Monona County, quoted and re-checked
- Chapter 100 Zoning Regulations, quoted and re-checked
- Private Water Wells & Onsite Septic Systems, quoted and re-checked
- Chapter 100 Zoning Regulations, quoted and re-checked
- Private Water Wells & Onsite Septic Systems, quoted and re-checked
- Chapter 200 Division of Land and Subdivision Regulations, quoted and re-checked
- Monona County Environmental Health & Zoning (mononacountyiowa.gov)
- Iowa Code § 91C.1 — Definition — exemption — combined registration and licensing process, quoted and re-checked
- Common Forms - Environmental Health/Zoning - Monona County, quoted and re-checked
- Monona County Floodplain Management Ordinance, quoted and re-checked
- Permit Application Fees, quoted and re-checked
- Common Forms - Environmental Health/Zoning - Monona County, quoted and re-checked
- Access Management (Iowa statewide rule), quoted and re-checked
- Chapter 100 Zoning Regulations, quoted and re-checked
- Chapter 100 Zoning Regulations, quoted and re-checked
- Chapter 100 Zoning Regulations, quoted and re-checked
- Iowa Code 2026, Chapter 335 — County Zoning (Iowa statewide rule), quoted and re-checked
- 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
- Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
- Iowa Code §335.30, Manufactured and modular homes (Iowa statewide rule), quoted and re-checked
- Chapter 200 Division of Land and Subdivision Regulations, quoted and re-checked
- Chapter 200 Division of Land and Subdivision Regulations, quoted and re-checked
Written October 10, 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.