This is a forgiving lot. World-class agricultural soils (Tama silt loam, hydrologic group B), gentle slope, no flood zone, no wetlands on the parcel itself. The one thing to watch is the intermittent drainageway about 220 ft from the suggested building envelope — Iowa enforces a Public Drainage District buffer in many areas, and counties typically require structures to be set back from defined channels. Otherwise, perfect for a country home or shop. Excellent infiltration means you can use simple drainage solutions; septic suitability is good if you're outside sewer service.
| Layer | Finding | What it means |
|---|---|---|
| FEMA flood zone | Zone X (unshaded) | Outside 500-yr floodplain. No federal flood insurance requirement. |
| Wetlands (NWI) | None on parcel | Two small PEM wetlands within 1/4 mile but none on the lot. |
| Soil (SSURGO) | Tama silt loam | Hydrologic group B. Drainage: well drained. Some of the best ag soil in the country. |
| Slope | 2.5% | Gentle. Standard grading, simple driveway, easy septic siting. |
| Elevation | 945 ft | Typical central Iowa till plain. |
| Streams (NHD) | Intermittent drainageway 220 ft | May be subject to Iowa drainage district rules. Verify with Story Co. Engineer. |
| Land cover | Cultivated crops (NLCD 82) | Currently row crop. Conversion to residential changes runoff CN from 78 to ~85. |
| Design rainfall | 100-yr / 24-hr: 6.2 in | Typical for central Iowa. Watch for short-duration high-intensity convective storms. |
Implications: Tama is one of the iconic prime farmland soils. Excellent infiltration, deep water table, low erodibility for the slope class. If on septic: percolation will likely be in the favorable range, but a soils evaluation by an Iowa-licensed Time-of-Travel evaluator is required for the actual permit. If a perimeter drain or basement foundation is planned, the deep water table is in your favor.
Implications: Many central Iowa parcels lie within historic drainage districts, which can impose maintenance assessments and setback requirements. Story County Engineer's office can confirm district status and required setbacks before you finalize a building envelope. The channel itself doesn't appear to be on a FEMA map, so flood-zone concerns are minimal — but local rules can still apply.
| Duration | 2-yr | 10-yr | 25-yr | 100-yr |
|---|---|---|---|---|
| 15-min | 0.65" | 1.02" | 1.24" | 1.56" |
| 1-hr | 1.36" | 2.18" | 2.69" | 3.49" |
| 24-hr | 2.78" | 4.31" | 5.18" | 6.20" |