What is potholing & daylighting?
Potholing is the most common hydrovac job we run. A small, precise test hole is cut with pressurized water and cleared with vacuum until the utility is visible. Your crew, engineer, or inspector can then measure its horizontal position and depth and record its size, material, and condition before any mechanical excavation starts nearby.
Daylighting is the same technique stretched over distance. Instead of one test hole at a single crossing, we expose a longer run of the line so you can see its full path. This is common when a utility bends, when records disagree with the locate marks, or when a new installation will run parallel and close to an existing line.
When you need it
- Before horizontal directional drilling crosses or parallels an existing utility
- Before driving piles, setting poles, or installing sign and signal foundations
- When locate marks conflict with as built drawings or each other
- During design, when engineers need verified depths for plans and conflict matrices
- Before trenching inside the tolerance zone of a marked facility
- When a line is unmarked, abandoned, or of unknown ownership
How we do it
Review the marks
We start from the existing Sunshine 811 locate marks and any plans you have, then set up the truck and protect the surrounding surface.
Cut the hole
A controlled stream of water breaks up the soil over the marked line while the vacuum hose lifts the slurry into the debris tank. Typical test holes are about 12 inches across.
Expose and record
Once the utility is visible we stop and let your team measure depth to top, offset from a reference, size, material, and direction. Photos are taken in the hole.
Backfill and restore
The hole is backfilled to your specification, compacted, and the surface is patched or left ready for restoration.
Tampa Bay conditions
Tampa Bay soils are mostly fine sand sitting over a shallow water table, with pockets of clay and limestone. Sand collapses quickly around a backhoe bucket and turns a small exploratory dig into a crater. A hydrovac test hole stays tight and vertical, and because the vacuum removes groundwater as it goes, you can still see the utility even when the hole fills from below.
What to include in your quote request
The more of this you can share, the faster and more accurate your quote will be:
- Number of test holes, or the length of line to daylight
- Approximate depth of the utilities
- Surface type at each hole: grass, asphalt, concrete, pavers, or brick
- Whether you need photos, depth logs, or GPS coordinates recorded
- Backfill and restoration requirements
Potholing & Daylighting FAQ
How many potholes can you dig in a day?
It depends on depth, soil, surface cutting, and travel between holes. Shallow holes in open sand go quickly; deep holes through concrete or clay take longer. Tell us the count and depths and we will estimate the time on site.
What is the difference between potholing and daylighting?
Potholing is a single test hole at one point to confirm a utility. Daylighting exposes a longer section of the line so you can see its route. Both use the same hydrovac process.
Can you cut through asphalt or concrete?
Yes. The surface is saw cut or cored first, then the hydrovac excavates below it. Mention the surface type so the right equipment is on the truck.
Do you provide depth records?
We can record depth to top of utility, size, material, and location for each hole, along with photos. Let us know the format your engineer or project manager needs.
Where we provide potholing & daylighting
We serve contractors and property owners across Hillsborough and Pinellas counties.