40 ENVIRONMENT and ENERGY
National Water Resources Strategy( Continued)
We continue with the extract from the National Water Resources Strategy 2 that was introduced in Plumbing Africa’ s March 2017 issue.
Existing initiatives on WCWDM by municipalities Despite the challenges mentioned earlier, it must be recognised that in many municipalities, considerable effort has been made to reduce water losses and NRW. While there is a need to intensify efforts to conserve water and curtail demand within the local government sphere, many metropolitan and other municipalities have responded to the need to address water losses within their jurisdiction by developing strategies and business plans, and are actively implementing WCWDM measures to reduce their water losses and improve water use efficiency.
Interventions being implemented include pressure management, retrofitting and removal of wasteful devices, improved management, sectorisation, metering, billing, development of by-laws, tariff reviews, mains replacement, leak detection and repair, awareness campaigns, asset management, operation and management, pressure management, and wastewater re-use.
While many municipalities have started with the implementation of WCWDM measures and others have made considerable progress, many municipalities still have to do much more to reduce their losses and manage water efficiently.
The WRC compiled the Compendium of WCWDM interventions and measures at the municipal level in South Africa( WRC TT519 / 12), in which a number of success stories have been captured. The measures implemented ranged from zoning to pressure management. In one example, water use was reduced by 50 %, resulting in cost savings of R29-million per annum and a total saving of more than R130-million( compared to a project cost of R9-million). NRW reduced from 37 % to 13 %.
Reconciliation strategies by DWA The DWA, now DWS, has been investigating the potential for WCWDM in many water management areas through the development of Reconciliation Strategies. Through these studies, targets to reduce the demand were set for the major demand centres( metropolitan and other municipalities with large urban and economic centres).
Irrigation The agricultural sector accounts for approximately 60 % of water utilisation in South Africa. It supports a significant portion of the South African economy and contributes massively to rural development. It assures food security for the country and contributes to job creation and employment throughout the food production value chain. Water conservation and water demand management must thus become entrenched in the agriculture sector.
• Many irrigation agricultural schemes experience water losses of between 35 % and 45 %. In the past, much of agricultural support tended to focus on issues relating to the repair of the infrastructure to ensure well-functioning irrigation schemes. Currently, however, many of these schemes are in a state of disrepair and some have exceeded their economic lifespans.
• The efforts to save water by this sector should be given high priority. A small percentage improvement in water use efficiency could result in a substantial reduction in water losses. In terms of water delivered on farms, all efforts must be made to use water efficiently from on farm storage, distribution systems, and in-field application, supported by best management practices.
• The greatest potential impact of WCWDM in the agricultural sector can be achieved by addressing wastage from conveyance losses and the inefficient application of water. Water wastage is classified as water, intended to perform a specific task, but not used for that purpose due to losses in transit. Examples of water wastage in the agricultural sector are seepage from irrigation canals( which causes water logging of adjacent land), loss because of percolation, evaporation from land surfaces, or polluted return flows.
• Employing efficient irrigation systems is paramount in improving water use efficiency on farms, such
April 2017 Volume 23 I Number 2 www. plumbingafrica. co. za