Many people have drilled wells, and they are common to see on a home inspection. But how do they work and what are some things to look out for?
With a drilled well, they will normally go between 100-400 feet into the bedrock. Commonly called ‘ledge’, this bedrock will be vital as the drilled well needs to intersect the fractures in order to find ground water. Let’s take a look at some of the key features of a drilled well;
- To prevent shallow ground water from making its way into the well, a casing made from metal or plastic will be extended into the bedrock. In most states, there will be a law for this and is likely to state 18 feet as the minimum distance with five of this going into the bedrock itself. After this, there should also be at least a foot sticking above the surface. To prevent surface water from getting into the well, it should also be capped whilst a sealant can be used along the top of the wall and outside of said casing.
- Within the well, a discharge water line will leave to enter the home and the more modern drilled wells will use a pitless adapter so that there is a sanitary seal in place. Below the frost line, this device will be attached to the casing and protects from both contamination and frost whilst providing a watertight sub-surface connection.
- Towards the bottom of the well, a submersible pump will be used. If the well has a shallow water table, a jet pump could be placed inside the home and these all need access to electricity and special wiring. For these devices to be installed, a trained professional that has the state registration will be required.
- Although the newer wells will have these sanitary systems in place, some older designs may not. Typically, an 8,10, or 12 inch well pipe was used in the past which was then covered at or below the surface with a concrete well cap. Over time, we have since found better solutions hence why this is now outdated and not used. Furthermore, older designs will rarely boast the pitless adapter which means that there is no seal from where the discharge occurs.