Data by place › United States › Washington

Washington Boring Logs & Geotechnical Data

187,122 public boring logs in Washington; 109,114 with digitized SPT, soil or CPT data; 78,008 scanned log PDFs. Sources include Washington Geological Survey, City of Seattle (EDMS), Washington State DOT (WSDOT), plus public reports found by web crawl. Free to search on the map, download or query by API.

187,122
Boring logs
109,114
Digitized
171,341
With PDF
641
CPT soundings
1966–2024
Drilled
21 ft
Typical depth (6 m)
Where the 187,122 logs are — darker cells hold more borings. Click to open the map.
Open the Washington map →

Where the data comes from

Web-crawled reports in Washington were published on, among others: apps.ecology.wa.gov, permitbulletin.mercerisland.gov, static.spokanecity.org, bellevuewa.gov, activeprojects.issaquahwa.gov, your.kingcounty.gov.

Counties with the most boring logs

CountyBoring logs
King141,866view on map
Snohomish13,008view on map
Kitsap5,069view on map
Pierce3,980view on map
Spokane3,727view on map
Clark3,232view on map
Cowlitz2,659view on map
Thurston2,626view on map
Grays Harbor1,510view on map
Whatcom1,150view on map
Skagit1,085view on map
Lewis940view on map

What's in a boring log from Washington

The 109,114 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 78,008 logs are scanned PDF reports — the original agency drawings — which you can open and download from the map. Holes are typically about 21 ft (6 m) deep; one in twenty goes past 84 ft (26 m). Not sure what a boring log looks like? See annotated example boring logs.

How to get this data

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 3 November 2026.

Other places

Florida (171,755)Ohio (80,951)California (75,550)Oregon (71,889)North Carolina (69,698)New Jersey (51,582) all regions →