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Methods of Digging or Getting to Underground Water

Water for human consumption comes from two sources. Aboveground water sources are streams and springs, and modern reservoirs collect rainwater. However, plenty of water finds its way underground; such underground water is valuable when surface water is in short supply. The traditional way of bringing up groundwater was by digging a well, but modern methods of digging or getting to underground water have changed that.

Dug Well
- Historically, men dug wells with a hand shovel until they reached the water table: the upper surface of underground water. According to the U.S. Geological Survey, during well excavation, the digger had to keep going until he was below the water table and the incoming water exceeded his bail rate. The digger then lined the well site with stones or any material that prevented collapse, and covered it with a cap of wood or stone. Diggers used their hands and rope to draw up the water in a bucket.
Driven Well
- With driven wells, you drive a small diameter pipe into soft earth such as sand or gravel until it reaches the groundwater. Then, you cover the bottom of the pipe with a screen that filters out sand and particles. One disadvantage of this method of excavation is that the water table must be fairly close to the ground surface for it to be used. Also, because the water is close to the surface, contamination is more likely.
Drilled Well
- Modern water wells are usually drilled. Workers use hand drilling as well as machine drilling methods. One of the advantages of drilling is that it can bring up underground water from a much deeper level. A mechanical drill operation involves a drill rig mounted on a truck. The rig uses different type of drill bits to get through the different layers of earth and rock. Rotary drill bits grind through the rock, while percussion bits smash the rocks when needed. Drilled wells can be up to 1,000 feet deep, and most have a pump installed at the bottom to push the water up.
Tube Well
- In many parts of the world, water supplies are inadequate for the population, and people either go thirsty or drink contaminated water that causes fatal disease. Hand dug wells don't resolve the issue, because they can't go deep enough to remove contaminants. A tube well is a type of water well that works effectively in these conditions. It is a stainless steel tube drilled into the ground with a strong electric pump at the top and a filter at the top. It is frequently used in areas of Bangladesh, Pakistan and India, where clean drinking water is difficult to obtain.

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