Buying Land in Story County, Iowa

Zoning and subdivision: one code, and a soil-quality-based lot-size exception

Story County has combined its zoning and subdivision rules into a single code, the Land Development Regulations, administered by the Planning & Development Department out of the county's administration building in Nevada. The framework sits under the county's Cornerstone to Capstone Comprehensive Plan, adopted June 7, 2016, which designates land near Ames as an "Urban Expansion Area" on its Future Land Use Map and sets aside priority farmland as Agricultural Conservation Areas. A required conceptual-review meeting -- an informal session with county departments to review preliminary plans, held virtually most Thursdays -- is the standard starting point before most development applications, and the seven-member Planning and Zoning Commission (all residents of unincorporated Story County) reviews cases monthly.

The county's agricultural zoning includes a detail worth understanding before you buy: the A-1 Agricultural District's standard minimum lot size for a dwelling is 35 net acres, but the county's Land Evaluation Site Assessment (LESA) system can qualify a specific tract for a reduced 1-net-acre minimum if it scores as lower-to-moderate-value agricultural land. A separate A-R (Agricultural Residential) district sets its own 1-net-acre minimum directly. In practice, this means two seemingly similar parcels in unincorporated Story County can carry very different minimum-lot-size rules depending on soil quality and district -- confirm a specific parcel's LESA status and zoning district directly with Planning & Development rather than assuming a countywide standard.

The Ames Urban Fringe Plan: joint city-county authority near Ames and Gilbert

Iowa law lets a city establish extraterritorial review authority over land divisions within two miles of its boundary, and in Story County that authority is formalized through the Ames Urban Fringe Plan -- a cooperative planning effort among the City of Ames, the City of Gilbert, and Story County, with the most recent cooperative agreement dating to 2011 and a public draft update circulated in 2022. Within the Fringe Plan area, the cities have review authority over land divisions in addition to the county, and the plan can require urban-scale infrastructure standards -- for streets, wastewater treatment, and potable-water distribution sufficient to support emergency services -- for subdivisions that fall inside that zone, a materially different (and often more demanding) standard than a subdivision further out in open county.

One notable feature of the agreement: because annexation by Ames or Gilbert would otherwise automatically extend the two-mile extraterritorial review area further outward, the cooperating parties agreed the cities would waive extraterritorial review jurisdiction in that newly extended area rather than let the review zone creep outward indefinitely. For a buyer, the practical takeaway is that a parcel's distance from Ames or Gilbert's current city limits -- and whether it falls inside the mapped Fringe Plan boundary -- can determine whether a future subdivision or land division needs city sign-off, county sign-off, or both, plus what infrastructure a subdivider would need to build. See our dedicated subdividing-land page for this county for how to check whether a specific parcel falls inside the Fringe Plan area.

Wells and septic: state Time of Transfer rules, with local scheduling extensions

Story County Environmental Health administers private septic and well permitting separately from Planning & Development, including compliance with Iowa's statewide Time of Transfer Septic System Inspection Law (in effect since July 2009), which requires a septic system to be inspected before a covered property changes ownership. Story County's own ordinance extends the standard permit's validity to two years and requires that requests for a final inspection be made within eight hours of the scheduled inspection time -- both administrative specifics worth knowing if you're timing a purchase, a new septic installation, or a Time of Transfer inspection around a closing date. The department's jurisdiction covers domestic and commercial wastewater from homes, small businesses, and non-residential outbuildings, plus private water-supply wells; reach the office at (515) 382-7240 for septic and well questions specifically, separate from Planning & Development's line.

Floodplain: the South Skunk River, and a documented history of major flood events

The South Skunk River and Squaw Creek run through Story County and the Ames area, and the county's Floodplain Management program (administered alongside Planning & Development) maintains current FEMA Flood Insurance Rate Maps for a specific parcel's flood-hazard determination, with a floodplain development permit required for construction within a mapped Special Flood Hazard Area. The area's flood history is real and documented rather than theoretical: major flooding hit the South Skunk River basin in August 2010, when 96-hour rainfall totals reached 9.61 inches at Ames and 8.70 inches at Story City according to a USGS report, and earlier floods in June 1990 and July 1993 affected Squaw Creek and the South Skunk River in and around Ames. A flood-protection wall built at Iowa State University was documented in a FEMA case study as having successfully withstood subsequent flooding. Pull the current FIRM for any parcel near the South Skunk River, Squaw Creek, or the Skunk River Greenbelt, and confirm floodplain-permit requirements directly with the county before assuming a parcel's distance from a visible waterway settles the question. See our national flood-zones guide for the general FEMA process behind these permits.