Possible water uses in mining lakes: case study of Aguas Claras, Brazil

The paper presents a Brazilian experience related with the decommissioning of an exhausted mining activity and the consequent formation of a pit lake. This water body, which is still in a process of filling, will reach the final depth of 234 m, being hence the deepest lake in the country. Since 2001 (first year of formation) the water quality has been monitored on a monthly basis. The aquatic environment is absolutely free from contamination and presents an excellent water quality. There is a marked shift in the dominance of algae groups, probably due to this early stage of creation of a new ecosystem. Some conflicts are now arising regarding the possible water uses. The high water quality allows a sound utilization for urban supply, but the manifestations of the population (through public hearings) is towards the utilization of the lake for recreational purposes and landscape harmony. The paper discusses the origin and possible solutions for these conflicts.