Top 5 Water Contaminants
If you are building a home, one of the first things you will need to consider is drilling your own well and planning your water supply. And, on your piece of land, that source could be anywhere- even where you wanted that two-car garage!
The first thing you need to do in this process is check with your local municipality or contractor to see it they require a permit for drilling a well. Being legal is important. The next step is to drill holes to find the best source, examining the ground basically for quantity and quality of water. Some things to look out for that cause low-yielding wells include a low natural or seasonal water table, interference with other wells (for example, in a subdivision) as well as geologic conditions. It is also recommended that a well be built first, prior to construction. This way, if there is a problem and a well needs to be rebuilt, there is still land available. Would you rather have a house built and all of a sudden- no water source available because it's underneath the bedroom? This also explains why sometimes you will see lots for sale with wells already built. There are several types of wells:
Drilled wells, while can be more than 1000-feet deep, are constructed by either cable tool or rotary-drilling machines. They penetrate unconsolidated material and require installation of casing and a screen to prevent inflow of sediment and collapse. The space around this casing must be sealed with grouting material to prevent contamination by water draining from the surface downward around the outside of the casing. Methods of drilling wells include air rotary, bucket auger, cable tool, down-the-hole and reverse circulation. Another type of well -- and an economic one at that--is the driven well, constructed by driving a small-diameter pipe into shallow water-bearing sand or gravel. A screened well point is attached to the bottom of the casing before driving. These wells are relatively simple to construct, but keep in mind that they can tap only shallow water and are easily contaminated since they are not sealed with grouting material. Hand-driven wells usually are only around 30 feet deep; machine-driven wells can be 50 feet deep or more. A third type of well is the dug well, historically excavated by hand shovel to below the water table until incoming water exceeded the digger's bailing rate. These wells were lined with stone, brick, tile or other material to prevent collapse, and then covered with a cap of wood, stone or concrete tile. Because of the type of construction, bored wells can go deeper beneath the water table than can hand-dug wells. There can either be hand-dug or machine-bored. There wells, since they are shallow and lack grouting, are easily contaminated and they can also go dry during periods of drought.
There are three main components to most wells: casing, cap and screen. In a drilled well, the casing is a tubular structure that keeps the contaminants from getting into the water supply. The most common materials for this are carbon steel, stainless steel and most prevalent, plastic. While plastic is much cheaper, more lightweight and more resistant to corrosion than steel, steel is stronger and more heat resistant. Well caps, which fit atop the casing, keep out debris, insects and other things we don't want in our water supply. They are usually aluminum on thermoplastic and should be placed six to eight inches above the ground. Finally, well screens prevent excess sediments from getting into the water supply.
The average cost of a well is $4500, but will vary depending upon local geologic and market conditions. While some wells are more prone to contamination than others, once dug and house is built and plumbing done- top it off with a water filter to ensure the utmost in safe drinking water! Read Next: My private well has an odor that resembles chloroform. What is the cause of this?