Springs, dug wells, and bored wells in North Carolina and North Georgia Mountains provide water from relatively shallow ground water sources and tend to be more susceptible to surface water contamination than drilled wells. If there is any question about the quality of water from these sources, the owner or potential buyer should have the water source evaluated by a professional.
Sometimes the local county health department provides this service, or it can provide the names of qualified consultants who do. Surface water contamination may be indicated by changes in color, odor, or taste of the water, especially heavy rainfall events. Positive coli form bacteria test results may also indicate surface water contamination.
Dug and bored wells typically penetrate unconsolidated materials such as soil, gravel and highly weathered rock. Deeper wells of this type (more than 20 feet deep), can provide safe drinking water supplies if properly constructed and protected, but shallow dug and bored wells, especially those near streams, or in flood plains, should be avoided. Dug or bored wells should be tiled and should have concrete poured around the outside of the tiles to a depth of at least 20 feet. A concrete slab should be poured around the tile at the ground surface and surface water should be diverted away from the site. The well should be sealed to prevent insects, rodents, amphibians, etc. from entering.
Springs can also provide safe drinking water supplies, but they must be properly constructed and protected to prevent contamination. Springs used as drinking water sources typically consist of a collection system or "spring box" to collect the water, a reservoir for storage, and piping system to transport water from the collection system to the reservoir and then to the home.
The following items should be considered in determining if a spring is adequate and safe:
* The better springs originate in bedrock (solid rock) as opposed to unconsolidated materials. Springs that originate in flood planes, low areas, drainage ways or valleys are much harder to protect from contamination than those originating in higher, well- drained areas.
*All parts of the system must be sealed to prevent surface water from entering and to prevent insects, rodents, amphibians, crustaceans, or other "critters" from entering.
* The area up slope from the spring should be free from development or heavy agricultural usage. there should be no potential contamination sources within 100 feet up slope of the spring.
* Burrowing animals up slope from the spring can lead to contamination. The area within at least 100 feet of the spring should be inspected periodically for signs of burrowing.
* Some springs cease to flow, or the flow drops considerably during late summer or fall. Before investing too much in developing a spring, flow observations should be made during dry periods to determine if the spring continues to flow. if the spring flow fluctuates significantly in response to rainfall events or seasonally, there may not be enough water to supply the home during extremely dry periods. If the spring has been in use as a drinking water supply in the past, previous owners or neighbors may be able to provide information regarding the flow.
* Spring flows as low as one half gallon per minute can provide adequate volume to serve a single residence. For low volume springs, a large reservoir is needed. The local health department or a professional consultant can provide information as to sizing the reservoir.
Drilled wells are the most common type of residential drinking water source for newer mountain homes. This type well is usually six inches in diameter, has a steel or thermoplastic casing extending to bedrock, and is drilled into the bedrock in hopes of encountering a water-bearing fracture zone. Drilled wells tend to be less susceptible to contamination than springs, dug wells, or bored wells, but in some areas the inorganic chemicals can be a nuisance. In other areas, there may be difficulty in drilling a well and getting an adequate yield.
There are state regulations on well construction that require that wells be "grouted" (concrete poured around casing) to prevent surface water or other contaminants fro entering the well. wells are also required to be tested as to the yield; a log is to be kept specifying the depth of the well, depth of the casing, depth of the yielding zones , and geologic conditions encountered. An ID plate is to be placed on the well indicating total depth, casing depth, the level water rises to, and the date the well was drilled. if this information is not readily available, the well drilling contractor may be able to provide it.
State regulations governing on site sewage (septic tank) systems and well construction standards contain separation distance requirements from several potential contamination sources, and, for most homes constructed since the mid 1980's these requirements have been met. buyers of older homes should check to see if separation distances are adequate to minimize the potential for contamination of the drinking water supply. For example, on site sewage systems are required to be a minimum distance of 50 feet from wells in all cases and in most cases are required to be 100 feet away. if springs, dug wells, or bored wells are down slope from an on site sewage system, an owner or potential buyer should seek advice from Environmental Health Specialist or a qualified professional.
If a drinking water source is tested for contamination and a problem is indicated, the owner or potential buyer should get help in interpreting the results from the local count health department or a qualified professional. if a drinking water test positive for coli form bacteria, the source should be disinfected (usually using chlorine) and retested. It is important to wait until all traces of the disinfectant are gone before retesting. If the water has tested positive , a series of test should be run over a period of time to make sure the contamination does not recur over time.
There are treatment systems on the market that are geared toward residential use; however homeowners should get professional advice before purchasing one of these units. Most small treatment systems are meant to take out a specific type of contaminant and if improperly applied, may cause a worse problem.
Some buyers are served by water sources on a adjoining property. if this is the case, a potential buyer should understand the water rights provisions and make sure there are legal rights that guarantee continued use of the water source and provisions for maintenance or improvements to the source. If a home is to be served by a community public water system, the potential buyer should find out who is responsible for maintaining the system -- a municipality, the developer, the homeowners, or a public utility. Information on public water systems can be obtained from your local Health Department.