Murphy's Law!
At Directional Drilling of Texas, we try to ensure nothing will go wrong, but to quote Robert Burns, “the best laid plans of mice and men often go awry”.
We always obtain details of existing installations by contacting 811 and mark these out clearly before we begin drilling. We also carefully plan the route the drill will take to ensure, as far as possible, that we will avoid anything that might cause a problem. We can choose to go around, under, or above any conduits or pipes that have previously been installed, and our locator is designed to ensure we know exactly where the drill head is going
The locator uses a handheld receiver (which often resembles a metal detector) to detect signals emitted by a transmitter (sonde or beacon) housed within the drill head. By moving the receiver along the surface above the bore path, the locator continuously monitors the signal strength and direction to pinpoint the exact horizontal and vertical location (depth) of the drill head.
The locator watches for any unusual signal readings or changes that might indicate interference, obstructions, or deviations from the planned path, and can scan the area for existing utilities or potential sources of interference.
There is, however, an exception to this. Locating equipment used in directional drilling is primarily designed to detect conductive materials (like metal pipes and tracer wires), it cannot directly detect non-conductive plastic or PVC pipes. This is where Murphy’s Law came into play.
We had successfully bored the required path, and all was well until we began to retract the drill with the conduit attached to the drill head. That’s when something went wrong! Despite the information provided to us, it turned out that we had drilled just below a plastic waste pipe that connected from a property to the mains in the road. As we withdrew the drill and conduit, we damaged that pipe and only became aware of its existence when water rose to the surface along with an unpleasant odor.
Seeing surface water does not necessarily show exactly where there was damage, so to discover the source required digging a fairly wide inspection hole to find the tube that had been broken. Once we found the damaged pipe, we then needed to ask the homeowner to stop sending any more wastewater so we could remove the water from the hole we had dug and gain dry access to the pipe to effect a repair.
We are fortunate to have qualified technical staff who were able to source the required pieces needed to deal with the damage and carry out an appropriate permanent repair. If you look carefully, you can see this in this photo, the conduit we have laid, which is the light green color running below the U-bend in the waste pipe.
Although this was not a serious incident, it did cause some concern to the homeowner and resulted in additional work for our crew to deal with, and delayed our completion of this particular task. Apart from the time, the actual repair costs were minimal, but this is one of the reasons why we carry a high level of public liability insurance. It provides security, ensuring that “if things ever do go wrong”, we are fully covered to effect any necessary reparations at no cost to the public.