Iowa Boring Logs & Geotechnical Data
2,720 public boring logs in Iowa; 2,331 with digitized SPT, soil or CPT data; 389 scanned log PDFs. Sources include Iowa DOT, University of Nebraska–Lincoln, Wisconsin DOT (WisDOT), plus public reports found by web crawl. Free to search on the map, download or query by API.
Where the data comes from
- Public reports collected by web crawl2,012
- Iowa DOT469
- University of Nebraska–Lincoln165
- Wisconsin DOT (WisDOT)46
- South Dakota DOT (SDDOT)23
- Missouri DOT (MoDOT)3
- Minnesota DOT (MnDOT)2
Web-crawled reports in Iowa were published on, among others: programs.iowadnr.gov, archive.epa.gov, bidopportunities.iowa.gov, apps.dot.illinois.gov, nrc.gov, navigationdistrict.org.
Counties with the most boring logs
| County | Boring logs | |
|---|---|---|
| Linn | 264 | view on map |
| Polk | 261 | view on map |
| Johnson | 252 | view on map |
| Woodbury | 159 | view on map |
| Clinton | 124 | view on map |
| Dubuque | 119 | view on map |
| Pottawattamie | 107 | view on map |
| Plymouth | 89 | view on map |
| Story | 87 | view on map |
| Poweshiek | 78 | view on map |
| Calhoun | 75 | view on map |
| Black Hawk | 62 | view on map |
What's in a boring log from Iowa
The 2,331 digitized borings carry the data engineers actually use: SPT blow counts (N-values) by depth, soil and rock descriptions, groundwater observations and, where the source ran cone penetration tests, CPT tip resistance and sleeve friction. A further 389 logs are scanned PDF reports — the original agency drawings — which you can open and download from the map. Holes are typically about 31 ft (9 m) deep; one in twenty goes past 177 ft (54 m). Not sure what a boring log looks like? See annotated example boring logs.
How to get this data
- Map — pan to a site, click a boring, and view the log, the original PDF, or an ML soil-profile prediction. No account needed.
- Downloads — every boring exports as PDF, DIGGS XML or AGS4; draw a polygon on the map for a multi-boring export or a site report.
- API — query borings by coordinates or bounding box, pull SPT/CPT/lab records, and generate site reports programmatically.
- Contribute — have Iowa boring logs that are not here yet? We take PDFs, DIGGS, AGS and spreadsheets.
This data was collected from public agencies and is republished as-is. It is a planning tool, not a substitute for a site investigation; see the terms and disclaimer. Counts refreshed 2 November 2026.
Other places
Washington (186,877)Florida (171,716)Ohio (80,944)California (75,283)Oregon (71,862)North Carolina (70,533) all regions →