The dominant reasons of water hardness are due to the exit of calcium and magnesium ions in the water. It is noteworthy to mention that hardness of water increases the cost of industrial and living activities. In many developed countries the hardness of water is deeply and broadly investigated. In developing countries such as Afghanistan, limited studies are available that have investigated this issue. Therefore, this study aims to investigate the hardness of water from deep wells as well as gully in different regions of Khost city, Afghanistan. We have collected data from 8 deep water wells and a gully located in different areas. It was observed that the permanent hardness of water was small; hence it was not considered in this study. Then we focused on investigation of temporary hardness of water from the above-mentioned sites.

Keywords : Hardness, Water, Afghanistan, Deep Water Wells, Gully.