What Is a Bore Log?
A bore log records depth, soil conditions, and utility crossings during directional drilling. Learn what it is and why fiber contractors keep one.
A bore log is a written record of a horizontal directional drilling (HDD) bore, capturing the drill path, depth, pipe locations, soil conditions, and utility crossings encountered underground. Fiber contractors use it to document as-built conduit routes, verify clearance from existing utilities, and give future crews accurate locate data before they dig near the line.
What Goes Into a Bore Log
A bore log tracks the drill in real time. As the operator pushes the bore head underground, the locate technician on the surface records depth and position at set intervals, usually every rod length or every few feet. The log also notes soil type, groundwater conditions, and the exact point where the bore crosses an existing water line, gas line, electrical conduit, or other telecom duct. Entry and exit pit coordinates, bore diameter, and the conduit that goes in the hole are logged as well. On a long bore under a highway or river, that running record is the only proof of what actually happened underground.
Why Fiber Contractors Keep Bore Logs
Underground plant is invisible once the ground is restored, so the bore log becomes the reference every future crew relies on. When a locate technician marks the ground before a homeowner digs a fence post or another contractor bores nearby, they're working off data that traces back to logs like this one. Bore logs also protect the contractor: if a dispute comes up about depth of cover or a utility conflict, the log is the record that shows what was actually installed and where. Fiber Construction Company keeps a bore log on every directional drill, then rolls that data into the as-built package delivered at project close-out.
Bore Log vs. As-Built Drawing
The two documents work together but aren't the same thing. A bore log is raw field data, the depth readings and notes captured while the drill is running. An as-built drawing is the finished map, built from the bore log plus GPS survey points, showing the final route on paper or in GIS. Think of the bore log as the field notebook and the as-built as the polished record handed to the customer or utility. Both matter: the as-built shows where the fiber ended up, while the bore log backs it up with the depth and soil data collected along the way.
Bore Log, answered
What Is a Bore Log?
A bore log is a written record of a horizontal directional drilling (HDD) bore, capturing the drill path, depth, pipe locations, soil conditions, and utility crossings encountered underground. Fiber contractors use it to document as-built conduit routes, verify clearance from existing utilities, and give future crews accurate locate data before they dig near the line.
Who creates the bore log during a fiber install?
The locate technician or drill operator logs it in real time, usually the same crew running the horizontal directional drill, using a tracking system that reads the drill head's depth and position as it advances.
Do bore logs get shared with the customer?
Yes. Fiber Construction Company includes bore log data in the as-built package delivered at project close-out, so the customer or municipality has an accurate record of what's buried and where.
Why does depth of cover on the bore log matter?
Depth of cover shows how far below grade the conduit sits at each point along the route. That number tells future crews how deep they can safely dig or plow before hitting the line.