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Gaborone, Botswana

The Department of Water Affairs is one of the departments of the South African government. In May 2009, following the election of Jacob Zuma, the Department of Water Affairs and Forestry was divided, with the forestry responsibility being transferred to the Department of Agriculture, Forestry and Fisheries. The Department of Water Affairs and Sanitation was established in May 2014 by President Jacob Zuma with former Gauteng Premier Nomvula Mokonyane becoming the first Minister. Wikipedia.

Kurugundla C.N.,Department of Water Affairs
African Journal of Aquatic Science | Year: 2014

The fruiting and seed dynamics of the alien invasive aquatic species Pistia stratiotes L. (water lettuce; Araceae) was investigated in the seasonally flooded Selinda Canal and Zibadianja Lake of the Kwando-Linyanti River system and in the perennial Chobe River, Botswana, in 1999-2003. The mean number of 30.3 seeds fruit-1 in the Selinda Canal is the highest ever recorded. An artificial earthen barrier or dyke was constructed on the Selinda Canal to allow manipulation of water levels downstream. By drying and subsequently reflooding a region of the stream, seed germination was stimulated, followed by the manual removal of water lettuce seedlings before their seeds reached maturity, which resulted in a decline in seed germination in surface sediment samples from 63.5% in 2002 to 31.7% in 2003. Manipulation of flooding, followed by the physical removal of P. stratiotes at regular intervals prior to anthesis and seed maturity, is considered the most viable strategy for arresting further additions to the seed bank, and could lead to its eradication in seasonally flooded areas where the biocontrol weevil Neohydronomus affinis has become locally extinct since its introduction in 1987. © 2014 Copyright © NISC (Pty) Ltd. Source

Seward P.,Department of Water Affairs
Ground Water | Year: 2010

In 1998, South Africa promulgated a Water Act that is widely regarded as one of the most progressive and enabling pieces of environmental legislation in the world. The environmental aspects of the Water Act are commonly referred to as " resource-directed measures." These measures attempt to find the right balance between (1) leaving water in the resource (" nonconsumptive use" ) to provide ecological goods and services for society and (2) taking the water out of the system for " consumptive" human use. These measures also attempt to ensure that both nonconsumptive and consumptive use is sustainable. This article discusses some of the challenges faced in using the measures to achieve environmentally sustainable ground water use. A major challenge is that misunderstanding still abounds regarding the environmental aims of this legislation. Other major challenges identified included a severe shortage of technical capacity, an inordinately long water use license application process, incorporating adaptive management to deal with uncertainty, incorporating the public participation process, and revising policy implementation processes to accommodate highly localized aquifers. Selecting appropriate scientific methodology-neither too simplistic nor too involved-is a recurring challenge. It is suggested that an important part of addressing these and the other challenges identified is a period of reflection and dialogue between the various sectors involved. Copyright © 2008 The Author(s). Journal compilation © 2008 National Ground Water Association. Source

Ravele A.M.,Local Government Planning and Coordination | Makhado R.A.,Department of Water Affairs
African Journal of Ecology | Year: 2010

This study has investigated the use and threats of Encephalartos transvenosus outside and inside Mphaphuli Cycads Nature Reserve, Limpopo Province, South Africa. Data were collected from 2005 to 2006 through social and ecological surveys. Semi-structured interviews were conducted with a total of 40 people per household, sampled from four selected villages around the reserve. E. transvenosus is used for medicinal purposes, decorations, cultural activities and as food. Youth and adult persons harvest E. transvenosus for income generation, while children and aged people mainly use it for subsistence purposes. The survival of E. transvenosus in the wild is uncertain due to various threats, such as illegal collection, habitat destruction, fire and grazing. Some conservation measures are also discussed. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd. Source

Makungo R.,University of Venda | Odiyo J.O.,University of Venda | Ndiritu J.G.,University of Witwatersrand | Mwaka B.,Department of Water Affairs
Physics and Chemistry of the Earth | Year: 2010

This paper presents a rainfall-runoff (RR) modelling method aimed at generating natural streamflow from the modified nearest neighbour regionalization approach applied to two ungauged sub-quaternary catchments (SQCs) nested within an ungauged quaternary catchment. It differs from the commonly used nearest neighbour regionalization approach involving a gauged quaternary catchment and an ungauged quaternary catchment. This approach ensures improvement in homogeneity of the estimated hydrological parameters. Lack of gauged streamflows hampers water resources planning and management, and water resources systems operation including allocations for environmental flows. The method has been applied in the Tshiluvhadi and the Nzhelele Rivers SQCs in quaternary catchment A80A of the Nzhelele River Catchment in the Limpopo River Basin. The modelling approach involved computing inflow hydrograph from a water balance model for Mutshedzi Dam. The hydrograph was then used in the calibration and verification of the RR model for the Tshiluvhadi River SQC using the Mike 11 NAM and Australian Water Balance Model (AWBM) in order to determine the model with better performance. The performance of each of the two models assessed by using the Root Mean Square Error, Nash Sutcliffe coefficient of efficiency, the correlation coefficient, % Bias and the overall water balance error was good and comparable. The two models, however, tended to underestimate the high flows. The models were used to simulate runoff hydrographs for the ungauged Nzhelele River SQC using model parameters obtained from the Tshiluvhadi SQC RR modelling. The streamflow hydrographs for the Nzhelele River SQC simulated from both the models are comparable and show behaviour similar to that reported in earlier studies. They also correlate well with the areal rainfall for the Nzhelele River SQC. The modelling results show that the approach is reasonably good and therefore can be used in predicting runoff in ungauged catchments. The simulated runoff hydrographs can be used in water resources planning and management, and water resources systems operation. © 2010 Elsevier Ltd. Source

Cochran B.,Clean Water Services | Logue C.,Department of Water Affairs
Journal of the American Water Resources Association | Year: 2011

Over the last five years, Clean Water Services developed and implemented a program to offset thermal load discharged from its wastewater facilities to the Tualatin River by planting trees to shade streams and augmenting summertime instream flows. The program has overcome challenges facing many of the nation's water quality trading programs to not only gain consensus on the frameworks needed to authorize trading, but also provide a broad range of ecosystem services. This paper compares the Tualatin case study with some of the commonly cited factors of successful trading programs. © 2010 American Water Resources Association. Source

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