Potholing

Potholing before a bore

Directional drilling has no eyes. A bore path crosses whatever is between entry and exit, and the only defense is knowing what is there before the head goes in. Potholing at each crossing turns an assumption into a measurement. Crews that pothole their crossings do not make the evening news. The pattern we see most often is a bore plan drawn off a set of as-builts that were accurate when they were drawn and have been quietly wrong ever since, because a service got relocated during a road widening and nobody redlined it. A test hole at the crossing costs a morning. Pulling a reamer through a fiber bundle costs a great deal more than that, and the cost is never only money. It is the outage report, the utility owner’s damage claim, and the conversation with the owner about why the schedule moved.

Small holes, small restoration

The finished footprint is small enough that restoration is a genuinely minor item. On finished commercial parking, tenant-facing frontage or a municipal sidewalk, that is not a small thing at all. On pavement we core the surface rather than break it, keep the plug intact, and set it back in when the hole is backfilled and compacted, so what is left behind is a seam instead of a patch. Municipal inspectors notice the difference, and so do property managers who have to explain a scarred lot to a tenant. On unpaved ground the disturbed area is small enough that turf and landscape recover on their own.

Reading the ground you are actually in

Pressure and nozzle get chosen for the material, and around here the material changes with the county line. Miami-Dade sits on oolitic limestone that can appear a couple of feet down, and it takes a tighter, harder pattern to break through the weathered cap without going wild once you are past it. The drained wetland muck out in western Broward and Palm Beach is the opposite problem, soft and wet and prone to caving in on itself, so the wand stays moving and the hole gets opened deliberately rather than fast. Sandy ground on the southwest coast around Fort Myers and Naples runs easy and sloughs easy. A crew that runs the same settings everywhere is either slow in the rock or careless in the muck.

What you get back from the hole

A test hole is a measurement, and a measurement nobody wrote down is worth almost nothing three weeks later when the design is being revised. Every pothole gets depth to top of pipe, outside diameter, material, condition of the coating or wrap where it is visible, and position tied to whatever reference you are working from, whether that is a station and offset, a survey point or a curb line. Photographs go with it, including one that shows the tape in the hole. Engineers get something they can put straight into a drawing. Field crews get something they can hand to the next shift.

Water table, traffic and the rest of the day

Two things decide how a potholing day actually runs in South Florida, and neither is the digging. The first is groundwater. The table sits high across most of the tri-county area, and closer to the coast it moves with the tide, so a hole that was dry at eight in the morning has water in it by noon. The vac truck handles that, since it lifts water and spoil together, but it changes how long a hole can stay open for somebody else to work in. The second is traffic control. Holes in a travel lane or a shoulder need a plan, a permit in most municipalities, and often a night window. We would rather sort that out with you in advance than find it out at the curb.

Worth knowing

Tell us what you are looking for and what you plan to do with the answer. A hole to confirm a bore depth and a hole to prove a conflict are dug the same way but documented differently.