Well construction combines geology, engineering, and public health to ensure a safe and reliable water supply. Dug/Bored wells are holes in the ground dug by shovel or backhoe. They are lined (cased) with stones, brick, tile, or other material to prevent collapse. Driven wells are constructed by driving pipe into the ground. Driven wells are cased continuously and shallow (approximately 30 to 50 feet deep). Drilled wells are constructed by percussion or rotary-drilling machines. Drilled wells can be thousands of feet deep and require the installation of casing.
Well Casing is the tube-shaped structure placed in the well to maintain the well opening from the target ground water to the surface. Along with grout, the casing keeps dirt and excess water out of the well. This helps prevent contaminants from less desirable groundwater from entering the well and mixing with the drinking water. Some states and local governing agencies have laws that require minimum lengths for casing. The most common materials for well casing are carbon steel, plastic, and stainless steel. Well Caps are placed on top of the well casing to prevent debris, insects, or small animals from getting into the well. Well caps are usually made of aluminum or plastic. Jet Pumps are the most commonly used pumps for shallow wells (depth of 25 feet or less). Submersible Pumps are the most commonly used pumps for deep private wells.
Proper well location and construction are key to the safety of your well water. The well should be located so rainwater flows away from it. Rainwater can pick up harmful bacteria and chemicals on the land’s surface. If this water pools near your well, it can seep into it and potentially cause health problems. Appropriate well construction depends on local geologic and groundwater conditions. Your state water-well contractor licensing agency, your local health department, or a local water system professional can provide information on proper well construction. Make sure any water-well drillers and pump-well installers you work with are bonded and insured. If required in your state, make sure your ground water contractor is licensed and certified. Visit the National Ground Water Association to find certified water well contractors near you. The NGWA operates its own voluntary certification program for contractors. This allows drillers, and well pump installers can receive national training certification on top of state requirements.
Before you build your house or drill your well, plan your water supply. A house is worth little without an adequate supply of good quality water, which may be found where you had hoped to build the front steps! Can an adequate groundwater supply even be developed at the property? A day’s use may be concentrated into a period of one to two hours, often in different areas of the house at the same time (laundry, bathroom, and kitchen). The water supply system must be able to meet this type of peak demand. A conservative estimate is that a home will need about 150-300 gallons per day for two to four people to meet all these needs. Attention should be given to choices of landscaping to be sustainable in a particular place, and alternatives to pumping groundwater, such as rainwater collection. In addition to providing for regular household use, some energy-conscious homeowners install groundwater geothermal systems, which use the constant temperature of the ground for heat exchange in order to provide heating and cooling in the home.
Key Components and Materials
The well screen is the most important part of the well: it attaches to the bottom of the long PVC well pipe and lets the water in, filtering out debris and sand. There will be a 4 inch (10.2 cm) space between the bottom of the 8 inch (20.3 cm) PVC pipe where there are no slits. Mark three slits circumferentially around the 8 inch (20.3 cm) pipe. The slits should be approximately 7 inches (17.8 cm) long and should be equally spaced apart. The gap between each slit should be approximately 1.4 inches (3.5 cm). Make sure your slit does not connect all the way around the pipe. Draw three more slits two inches above the first set of slits. Keep drawing sets of three slits, all two inches apart. You can stop when the screen reaches 6 feet (1.8 m) in length. Using a hacksaw, cut out the slits according to the lines you drew. Carefully saw each line, making sure not to cut all the way through the pipe. You’ll need to find a PVC cap to the end of the well screen. Make sure that it fits the well screen snugly. The primer will help hold the end cap onto the screen and prevent any leakages. Once you’ve applied the primer to the end cap, turn to the well screen. Apply the same amount of primer around the mating portion of the well screen. Apply pipe cement over the primed pieces. You’ll have to work quickly here, as the cement dries quickly. Again, work quickly. Hold the end cap onto the screen for fifteen seconds to allow the cement to dry. The foot valve is the mechanism that allows water to be drawn in but does not allow water to escape back out. There are two-foot valves used in this well. The first one is at the bottom of the six-inch PVC pipe and the second one is at the bottom of the 4 inch (10.2 cm) PVC.
There are several choices when it comes to boring your well. You can use a hand auger, a well point, or a DIY drill. Each method involves different equipment, but all will require a lot of physical labor. Note that these methods will only work well in soil, soft gravel or other softer land types. Rocky terrain or soil with a high clay content may require a professional drilling rig. Reach your required depth. Using your chosen method, work until you reach the depth you want for your well. If you want to check to see if you’ve reached water, tie a small rock to a string and feed the string down the hole. When you feel the rock reach the bottom of the pipe, pull it back up. For the hand auger method, you will need an extendable auger and a lot of patience. Turn the auger in a clockwise direction into the ground. This will move the earth and create the beginning of your hole. Remove the auger when full. Once the auger is filled with dirt, you will need to empty it. Pull the auger out of the hole and dispose of the earth. Continue to bore into the ground. Continue drilling deeper, always moving clockwise. Extend the auger when it becomes too short. Add a drill rod to the auger when it can no longer reach the bottom of the bored hole. Drill until you reach your desired depth. Depending on how deep you want your well to be, continue to add extensions to your auger as you drill to that depth. Once you’ve reached the bottom of the well, stop drilling and remove the last bit of dirt. This method can be easier than the auger method and requires less specialized tools.
Start a pilot hole. Using a post hole digger or shovel, dig a hole two feet deep. This will give you a good starting point. Install your well point. Well points are generally made of steel or any other hard metal so that they can withstand being driven deep into the ground. Begin driving the well point. If the soil is soft enough, you can use a rubber mallet or other heavy hammer to strike the end of the PVC pipe section, driving the pipe into the ground. If the earth is harder, you can use wrenches to turn the pipe, screwing it as you would a screw into wood. Add each extension of pipe. The end of the pipe that you are striking or screwing into the ground will continue to get closer and closer to the ground. As it becomes level with the earth, add the next length of pipe, screwing the joints together.
The well above is violating the minimum 50 feet distance requirement for a corral. If a pitless adaptor is installed in your well it must be done in such a manner as to provide a leak-proof seal. If maintenance is being conducted on a well with a pit, the Kentucky certified well driller must eliminate the existing well pit and extend the casing a minimum of four (4) inches above the finished ground surface. When a water well is abandoned, it must be plugged by a Kentucky certified well driller in a way that prevents surface water or contaminants from infiltrating the aquifer.
Drilling a well can provide a sustainable source of clean water, but having it drilled with professional machinery can be expensive. Luckily, there are many methods of drilling a well that don’t require costly equipment or contractors. In most states, it is legal to drill your own well. However, in some states, you must have a permit to drill over 200 feet, so you may need to get the permit or have the well professionally drilled. Septic tanks, muddy areas, sewers or animal pens can all potentially contaminate wells. Waste matter leeches through the soil, all the way down to the water reservoir: anyone who drinks water from a well drilled near these areas could get sick. If you live in a populated area, you will want to check with your local utility companies before you drill. Many electricity, gas and telephone companies run conduits underground, so any drilling could interfere with or strike their lines.
Location, Environmental Considerations, and Maintenance
Different factors on your property will give you information about how much water to expect to get from underwater reservoirs. Areas with heavy sand and gravel deposits often yield water. The larger the pieces of gravel or sand, the more water is most likely beneath the surface. Vegetation can tell you the location of water. In arid climates, locations with greater number of plants growing indicate water below the surface. Topography can help you make your choice. Areas of lower elevation, such as the bottoms of valleys or hills often yield more water. It may also be helpful to call your county survey office or other planning organization and ask for groundwater maps.
The well screen is the most important part of the well: it attaches to the bottom of the long PVC well pipe and lets the water in, filtering out debris and sand. There will be a 4 inch (10.2 cm) space between the bottom of the 8 inch (20.3 cm) PVC pipe where there are no slits. Mark three slits circumferentially around the 8 inch (20.3 cm) pipe. The slits should be approximately 7 inches (17.8 cm) long and should be equally spaced apart. The gap between each slit should be approximately 1.4 inches (3.5 cm). Make sure your slit does not connect all the way around the pipe. Draw three more slits two inches above the first set of slits. Keep drawing sets of three slits, all two inches apart. You can stop when the screen reaches 6 feet (1.8 m) in length. Using a hacksaw, cut out the slits according to the lines you drew. Carefully saw each line, making sure not to cut all the way through the pipe. You’ll need to find a PVC cap to the end of the well screen. Make sure that it fits the well screen snugly. The primer will help hold the end cap onto the screen and prevent any leakages. Once you’ve applied the primer to the end cap, turn to the well screen. Apply the same amount of primer around the mating portion of the well screen. Apply pipe cement over the primed pieces. You’ll have to work quickly here, as the cement dries quickly. Again, work quickly. Hold the end cap onto the screen for fifteen seconds to allow the cement to dry. The foot valve is the mechanism that allows water to be drawn in but does not allow water to escape back out. There are two-foot valves used in this well. The first one is at the bottom of the six-inch PVC pipe and the second one is at the bottom of the 4 inch (10.2 cm) PVC.
Test your water quality. Draw up some water from your new well to make sure it works. Before you drink or use any of the well water, you’ll want to have it tested to make sure there is no bacteria or other contaminants in the water. Drilling a well can be expensive, so ensure you meet local regulations and obtain any necessary permits. The development process maximizes flow to the well by removing any remnants from the drilling process and fine sediments from the vicinity of the intake. The borehole should be made larger than the casing to prevent caving in and to allow proper placement of grout and screens. The annular space between the casing and the bore hole must be properly sealed with neat cement grout or bentonite clay grout, to prevent the entry of contaminants into the aquifer. The casing of the well should be sealed to protect groundwater quality and public health. A concrete slab should be poured around the casing, extending at least 2 feet from the outer casing in all directions and sloped to shed water. This slab helps stabilize the casing and the soil immediately around it. All piping, wiring, and air vents should enter the well at least 8 inches above land surface unless a pitless unit is used, which has its own requirements.
In addition to proper construction, ongoing protection of the wellhead area is crucial. It is essential to avoid mixing agricultural chemicals or other contaminants near the wellhead and to prevent back-siphoning or spills that could enter the water supply. Regular testing for contaminants and maintenance of barriers against contaminants form part of best practices for long-term water quality. Abandonment procedures require sealing wells that are no longer in use to prevent contaminant infiltration into the aquifer. Always verify current regional regulations and ensure that any work complies with state and local standards. The general guideline emphasizes planning, proper siting, correct casing, appropriate sealing, correct screen installation, and responsible maintenance and testing to ensure a safe and reliable well water supply.
Practical Steps Summary
- Plan location with consideration of drainage, contamination sources, and future maintenance needs.
- Choose appropriate well type (dug/bored, driven, or drilled) based on depth, yield, and geology.
- Install proper casing, cap, and sealing grout to protect groundwater quality.
- Install a suitable pump and ensure correct alignment and connections.
- Prepare a well screen with correct perforations and attach a cap and end seal.
- Conduct water testing for contaminants and ensure compliance with local requirements.
- Monitor and maintain the well, and seal abandoned wells to prevent contamination.
