As part of the project to digitize oil and gas well locations, Survey staff and interns have created a new series of digital base maps for the state. Prior to this effort we had been using the digital base maps from the Ohio Department of Transportation. However, we found that certain layers (e.g., township and section lines) in their files, which were of prime importance to this project, were not digitized with sufficient accuracy for our needs. Further, nobody had ever digitized all of the irregular land subdivisions for the entire state. As most oil and gas well locations are surveyed from the subdivision boundaries, these had to be included on our maps.
The Survey was aided in this task by having available the new Digital Line Graph (DLG) files for most of the
state. These files are vectorized, digital representations of the USGS 7.5-minute topographic quadrangles that are being produced under a cooperative program between Ohio and the USGS. We used the county and township boundaries and public land survey system (PLSS) layers from these files where available. In areas not yet completed with DLG's, we digitized those elements from USGS quads. For consistency, when the DLG program is complete we plan to capture the boundaries from the DLG's in areas that we digitized in this effort.