Michigan Geological Survey nears completion of 1.1 million well‑log cleanup, staff say

Sarah Pearson, director of the Michigan Geological Survey, told the Water Use Advisory Council that contractors and survey staff are in the final stretch of a multiyear effort to correct and geolocate the state’s WellLogic well‑log inventory.

Pearson said the project has touched more than 1.1 million well records and that the team is “well over 90% completed” and on track to finish by the end of the current contract period. She described the effort as the migration and manual correction of scanned paper well records and older database entries into a single searchable dataset.

The work includes locating wells that were originally entered with only coarse section‑centroid coordinates, reconciling scanned paper logs with database entries, and flagging records that lack sufficient location or construction details. Where possible, MGS uses automated scripts to identify likely bad locations and then staff or contractors perform manual corrections; for the most difficult records the team is working with EGLE drinking‑water staff, local health departments and drillers to “sleuth” correct locations or note insufficient information.

Council members and staff emphasized how many records contained errors. One attendee noted that roughly two‑thirds of records examined had some kind of error; Pearson said many errors reflect older recordkeeping practices before GPS and standardized forms were common. The project team is also conducting targeted gamma logs and deeper borings in demonstration counties to validate lithology in areas where water‑resource mapping will be used.

Pearson and other council members said the cleaned WellLogic dataset will be integrated with the state’s ECWIS system so the public and agencies can access improved records. Staff also said the migration effort produced methods and scripts that they plan to reuse to sweep previously corrected counties for additional touch‑ups.

Council members urged the department to document the time and cost per record for the cleanup, and to publish lessons learned and the QA/QC approaches used, so other divisions and external partners can plan similar data modernization efforts.

The council discussed next steps for adding professionally logged geotechnical and monitoring‑well data — including gamma logs, slug tests and geotechnical borings — to strengthen lithology and hydraulic parameter data. MGS said it is adding limited additional borings to support mapping in selected counties and that the state will continue to pursue means to gather professional logs from other state programs and contractors.