For years, the drillers in this area have struggled with casing collapse.  The column on the outside of the casing fills up with seep water, while the water inside the casing pushes back out.  When the water level drops during pumping, the water on the outside pushes in on the casing.  This is even worse during drought periods.  If the pressure on the casing is more than it is designed to handle, then the casing will collapse. This ruins the well and in many cases, captures the pump.

PVC casing is widely used because of it’s low cost and efficiency.  However, PVC is not strong enough for the deeper wells that we have in our area. Many wells have collapsed recently.  During recent summers, many wells that were cased with PVC have collapsed due to low water levels.  We ran cameras into some of the wells and captured pictures of the collapse. Our customer have grown tired of PVC casing in deep wells.

For many years, the only other option has been steel casing, which is very expensive, and adds a problem of rust.  Eventually, the steel will rust out and will need to be replaced.

A third option has finally been introduced. Fiberglass casing that has been used in the oilfield market is now available for water wells. It is ANSI/NSF Standard 61 certified for potable water. It has a collapse pressure rating of 600 psi. That is 1386 ft. of water pressure.  The graph to the right shows rated collapse pressures for PVC and fiberglass.  The working pressure should be no more than half of the collapse pressure. The fiberglass has one other advantage. It can handle temperatures up to 300 degrees.  It won’t melt like PVC does if the pump fails. If you are drilling a deep well, consider using fiberglass casing. It will pay for itself in the long run.