Drinking water quality in rural areas

Abstract

Dug wells are usually not very deep, filled with water from shallow recourses of ground water that is why ground water is extremely sensitive to chemical and microbiological pollution. It is very important to estimate the level of pollution and effect these factors have on the quality of water in dug wells as only in such case solutions to decrease pollution level could be taken. The objective of this studyis to estimate pollution level in water of dug wells, to determine the effect of pollution stipulating factors on pollution of dug well water, to estimate the realization in rural areas of requirements for water protection from pollution with nitrogen compounds from agricultural sources. It has been found that most wells in rural areas were built without observing safe distances from sources of pollution. Only 18% of all wells examined corresponded to the rules of establishment. That was the reason why in 52% of examined wells in Lithuania the water was found polluted with nitrates, in 63% of wells pollution with organic matters was unacceptably high. In certain regions all wells were polluted. Having carried out a multiple regressive analysis of risk factors effect on nitrite concentration in the water of dug wells, it was found that the distance to the source of spot pollution as well as the depth of the well had the greatest effect on nitrite concentration in dug wells‘ water. Regional maps were made for Lithuanian dug wells according to their pollution with nitrogen compounds. It has been found that after pollution sources had been eliminated in 1998, pollution level in dug water of a sample object did not decrease until 2004. It demonstrates that the process of purification of dug water takes a lot of time.