Water resources issues in Tarkwa municipality, southwest Ghana

Abstract

Tarkwa is an old and important gold mining town located in a sub-humid tropical climate with its economy built on mining and allied services. The current high gold price has generated a vibrant local economy in Tarkwa and increased its population and water use. Consequently, the water resources of Tarkwa are getting under pressure. Data on the annual ratio of water produced by Ghana Water Company Limited (GWCL) at the Bonsa Treatment Plant (BTP) to population growth of Tarkwa from 1987 to 2008 reveal an amount of 76 litres/person/day in 1987 decreasing to 40 litres/person/day in 2008. These figures show that the amount of water produced over the years has not kept pace with population growth in Tarkwa. Additionally, Unaccounted For Water (UFW) is very high, although it is gradually being reduced from 66 % in 1991 to 34 % in 2007. As a result of the inadequate water provided by GWCL, more than 318 wells have been constructed in Tarkwa. However, most of the wells were constructed without recourse to professional advice and preliminary results have revealed that some are biologically and chemically contaminated while others are at risk of becoming contaminated. Additionally, inadequate waste disposal practices, building on hills and in recharge areas, washing of cars into receiving streams, illegal mining and its processing also into receiving streams suggest that surface and some ground water are being contaminated. A comprehensive water resources management plan in the form of an environmental impact statement including the delineation of groundwater protection zones is recommended to address water issues in Tarkwa. Public education on environmental issues, enactment and enforcement of by-laws arising from this plan should be implemented.