Water compositions and attitudes to a rooftop rainwater harvesting system : a minor field study in Killarlahalli, India

Abstract: The ground water of about 4500 villages in the state of Karnataka is not fit for drinking purpose due to high fluoride content, iron content or brackishness. Long term consumption of fluoride contaminated water causes the disease fluorosis. In 2007 fluorosis was reported to over 20 states and more than 66 million people are at risk, indicating that endemic fluorosis has emerged as one of the most alarming problems of the country. In the rural village Killarlahalli outside Pavagada is the average fluoride content in the ground water measured to 2- 4mg/l. The WHO (World Health Organization) drinking-water guideline value for fluoride is 1.5. The Indian Government and States have made policies to decrease the lack of drinking water by promoting organizations and the private sector to participate in the construction. The BIRD-K organization (BAIF Institute for Rural Development-Karnataka) has during a three year long pilot project, together with Rainwater club constructed rooftop rainwater harvesting systems and tanks in Killarlahalli. During the time the project has been running the idea of possible contribution of minerals to the drinking water, to prevent malnutrition, was made. Before further investigation of the possibilities, a platform of information about the socio-cultural perspectives and the water composition was needed. The aim of this study is to investigate the social-cultural aspects to understand the culture, custom and traditions which affect the purchase of rainwater harvesting system. It is also to investigate the mineral content and total organic carbon, TOC in rainwater. The study indicate that the tanks are sufficient used by the owner but that there are variations in pH between the tanks. Analysis of cations shows that Ca2+ has a very high and varied concentration in the water tanks. This indicates that Ca2+ is contributed from the tank or filter to the water. In an socio-cultural perspective education, experience and active participation are the key words for the information flow and work for water tanks development to become more acceptable and interesting for those who are involved.