About 3.7 million people live in Kentucky, of which 1.9 million (52 percent) live in urban areas (roughly defined as any community with 2,500 or more people) and 1.8 million (48 percent) live in rural areas (University of Kentucky, 1993). About 70 percent of Kentuckians get their daily supply of water from surface-water sources - lakes and streams; about 25 percent get their water from ground-water wells; and about 5 percent get their water from other sources - springs, cisterns, ponds, or hauled water.
About 3 million Kentuckians (80 percent) get water from public systems. The remaining 720,000 people, or 40 percent of all rural Kentuckians, rely on private water systems. Over 200,000 private wells provide most of this water. Wells and springs also provide drinking water for schools, restaurants, gasoline stations, livestock, and irrigation (Kentucky Department of Natural Resources and Environmental Protection, 1992).
Not all ground water is safe or pleasant to drink. In some areas, natural conditions render water unpalatable, if not hazardous to health. In other areas, human activities have contaminated ground water. Most studies of ground water have focused on areas of high vulnerability to pollution. Reports from such studies may have exaggerated the extent of ground-water contamination, adversely affecting the public's perception. In the absence of mandated routine testing for private water supplies, the information available is largely associated with testing in response to complaints. Such information is likely to be biased toward those private systems having water-quality problems. Information about "typical" private water supplies is scarce.
In general, much less is known about the quality of private water supplies than of public water supplies. Public water supplies are regulated by the Safe Drinking Water Act of 1974 to ensure that they are safe. Treatment plants utilizing surface water have more stringent testing requirements than those using ground water. Monitoring and testing by the Kentucky Division of Water provides information on the quality of drinking water for approximately 860 public water systems in Kentucky. Testing focuses on those chemical and biological constituents, such as metals and coliform bacterial, for which safe drinking-water standards have been established.
Such testing is not required for private systems. The only testing requirement for private water systems is a bacteria test that must be completed when a well is initially installed (401 KAR 6:310, Section 10). Where pollutants in private water systems are found to be in excess of safe drinking-water standards, water treatment may be used to reduce concentration levels. Costs per household are very high, however, when compared to treatment costs for public systems. This high treatment cost is one of the reasons that protecting ground water from pollution is important.
At a time when surprisingly little information is available on ground-water quality, ground-water contamination has become one of the major environmental issues of the current decade, and will likely remain so into the next decade. Reliable information about water quality is necessary in order to develop plans for protecting ground water. The absence of accurate and broad perspectives on ground-water quality may lead to inappropriate and ineffective regulatory policies. Because ground water supplies a large percentage of rural drinking water and water for agricultural use in the state, rural landowners have become increasingly concerned about the quality of ground water.