Despite of Lesotho having abundant water, it is still faced with freshwater challenges as the current water supply cannot meet the needs of the population. In addition, water has become the main driver of development in Lesotho as it is one of the few natural resources of economic importance hence construction of water storage dams has been identified as a development strategy. Modelling of water flow is one of the techniques used in describing the movement of water and determining flow accumulation within the catchment. Rainfall-runoff modelling in Lesotho has been based on traditional methods which only focus on the discharge at the outlet neglecting the distribution of runoff over the catchment. GIS enables modelling of spatial variability hence this study is aimed at determining flow distribution and accumulation within Phuthiatsane Catchment and estimating runoff potential in a GIS environment. In order to achieve this, ArcHydro extension of ArcGIS was used in the determination of flow distribution and subsequent catchment delineation while ArcCN-Runoff tool was used to determine the potential runoff based on land cover, soil type and amount of rainfall. The delineated catchment covers an area of 468 km2 and has an average runoff of 30.943 MCM. Suitable dam sites, volume and the areas that would be submerged were then identified using other ArcGIS tools. It was concluded that GIS can produce accurate hydrological modelling results for Phuthiatsane Catchment. Simulation of dam sites and storage capacities has also proven to be efficient in GIS environment and a 70m high dam with a storage capacity of 327.92 MCM was considered to be the most suitable. It is recommended that further research should include ground truth surveys for the validation of results. Further research should also incorporate stakeholder concerns in deciding on the location and size of a dam. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.

In the Kingdom of Lesotho, large dams are currently being constructed with the sole purpose of selling water to the Republic of South Africa, in order to earn royalties and to generate electricity for Lesotho. The focus of this study was to investigate the perception of the community on the socio-environmental impacts of Metolong Dam and Reservoir in Lesotho. A qualitative research methodology was adopted and grounded theory was used in collecting data from the study area. Qualitative research techniques used were document analysis, field notes and semi-structured interviews. After conducting an audit which evaluated the accuracy of the initial Environmental Impact Assessment (EIA) by comparing actual to predict impacts, it was found that the perceptions of the community on the socio-economic impacts of Metolong project were: the community had poor education due to expensive school fees and their level of education did not help with dynamics on climate for they are complex and not easily to be understood, alcoholism existed due to unemployement, cultural constraints existed dominated by the patriarchal structures on the land and decision making, compensation policy was not honoured by project developers, the project brought benefits and loss of life-support resources, people are unable to grow wheat, beans and peas for their fields are taken and the community experienced loss of building sand that is not addressed. Information obtained helped the study to close the gap which appears not to have been addressed by the Government of Lesotho Department of Water Affairs Lowlands Water Supply Unit, 2008. Results of the study revealed that local villagers in the study area were happy with the project benefits, but they were discontented with the project as they were not incoporated in the management and supervision of the project. Rather, the local villagers were engaged only as labourers. The study recommends that when large dams are constructed, local villages should not be given promises that are dressed with many enticing commitments. The reason is that, communities never asked for the project, but it is set forth authoritatively as obligatory upon them. Project authorities should increase their efforts to fulfil promises made. Not only that, they should have respect, compassion, care and dedication when dealing with affected people. It is in this regard that the Local Based Project Execution and Observation Model is proposed, which will incorporate local villagers in the management steps of all large dam developments within their communities, in order to contend with environmental impacts of large dams. / Environmental Sciences / Ph. D. (Environmental Management)