Assessment of Water Hardness Used for Domestic Purposes in Some Tribal Villages of Dhakuakhana Sub-Division, Lakhimpur District, Assam

The quality of water varies widely with respect to its various uses, and the water quality suitable for one purpose may not be satisfactory for the other. Statistical studies have demonstrated significant inverse relationship between cardiovascular disease (CVD) mortality and water hardness even when the environmental and socioeconomic factors are taken into account. The evidence that drinking water quality affects cardiovascular disease has been strengthened by recent research which has shown that very soft water increases CVD and mortality rates by 10%. Keeping this view in mind the assessment of water hardness of this region along with some polyvalent cations (Ca, Mg, Fe) has been carried out for three different seasons in a year. The study reveals that water quality in the study area falls under moderately hard (60-120mg/L) and hard (120-180mg/L). Also it was found that Fe content in the study area was very high as compared to the WHO value of safe drinking water, while other parameters (Ca, Mg ) were within the WHO limit.