What this is
The Testholes UNL layer records locations and data from test holes drilled by the Conservation and Survey Department (CSD) at the University of Nebraska-Lincoln. Test holes are drilled to obtain geoscientific data about the substrata, groundwater, and natural resources underlying Nebraska — the CSD Drilling Program drills an average of over 10,000 feet annually and has drilled nearly a quarter-million feet of subsurface data across the state.
Why it matters to you
If you’re drilling a water well, evaluating a site for construction, studying groundwater availability, or researching the geologic history of a part of Nebraska, the testhole record tells you what was found at that exact location — soil and rock layers, depth to water, subsurface conditions, and any notable features encountered during drilling. This is primary field data, not a generalized map, and it represents actual observations at specific points across the state.
How to read this data
Each point represents a drilled test hole with associated subsurface data. The layer is most useful when you’re looking at a specific area and want to know what has already been documented underground nearby. Well drillers, geologists, engineers, and researchers use these records to infer subsurface conditions before starting new work — they show what was found at known locations rather than predicting what’s under every property.
Where this leaves you
Testholes are point locations — each one is a specific drilled site with documented observations. You can look up whether a testhole exists near your property, but the data describes what was found at that drilled point, not a continuous subsurface profile between holes. For your specific property, the nearest testholes give you a regional indication; a new site-specific investigation may still be needed.
Look it up yourself
Open the map and zoom to your area. Point locations show where test holes have been drilled. Click or tap a point to see the available data for that hole — depth, observed layers, and other documented findings. For a specific property, use the nearest testholes as a guide and contact the UNL CSD for additional records or to discuss whether a new investigation is warranted.