Freshwater Supply per capita expected to Halve

The World Resources Institute rates South Africa’s current yearly renew- able freshwater supply between 1 000 m³ and 1 700 m³ per capita, but this is likely to descrease to less than 500 m³ by 2025.

The institute says that any amount less than 1 000 m³ a person means that water stress will start to deter economic develop- ment, environmental sustainability and human health.

To prevent this dangerous consequence, South Africa needs to invest R2,6-billion a year in water infrastructure maintenance and development until 2030, or face the possibility of severe water shortages. While it would seem that the risk is decades away from becoming a reality, it takes 20 years to build a new dam, and current infrastructure must be adequately main- tained or replaced to keep pace with this timeline.

“It is critical that we focus firmly on all aspects of water management to ensure that this vital component of life is readily available today and into the future,” South African Association of Water Utilities (Saawu) CE Ntombenhle Thombeni says.

Saawu business analyst in the office of the COO Richard Holden adds that a major need for South Africa currently is the introduction of water demand management to curb the growth in demand for water. “Although the Department of Water Affairs (DWA) has produced numerous documents over the years, pointing to there being no surplus water to allocate by 2025, there has been no noticeable reduction in the growth of water demand,” he says.

“If this trend continues, it will result in drastic interventions needed to curb demand in the future. The consequences of the approach of waiting until there is a crisis are now seen with acid mine drainage (AMD). The problem has been common knowledge for years, but no one has been prepared to do anything about it, least of all consumers, who are paying higher prices for water,” he notes.

Another issue compounding the looming water shortages of the future is the fact that not enough young water engineering professionals are entering the industry.

“Although the condition of water engineering in South Africa is fairly sound, and is comparable with the best in the world, several key challenges, including the growing demand for water and the need for younger people in the water sector, prevail,” South African Irrigation Institute president Jaco Burger says.

It is his opinion that the most significant development in the foreseeable future in the water sector will be in the establish- ment of catchment management agencies, water user associations and the transfer of many DWA functions to these institu- tions. “This should significantly improve the efficient use of water,” he adds.

Burger believes that the greater the demand for water becomes, the more relevant professional people in the industry will become and pressure on these professionals will increase to find unique solutions for unique local problems and challenges.

Meanwhile, progress is being made on a number of key water projects in the country. The Lesotho Highlands Develop- ment Authority reports that phase two of the Lesotho Highlands Water Project is making significant progress.

This phase will see the construction of the 165-m-high, 2,2-billion-cubic-metre- capacity Polihali dam, at Tlokoeng, in Lesotho. The bulk of the construction capital is being provided by South Africa, including the construction of tunnels, roads, elec- tricity and water supply, as well as the associated social and environmental aspects of the affected communities and areas.

The project will add to the current hydropower generating capacity of Lesotho, and will benefit the country and regional con- sumers in South Africa.

Phase one of the project is complete, comprising the 185-m-high double-curvature concrete Katse dam, the 145-m-high concrete-faced and rock-filled dam wall for the Mohale dam, with interconnecting tunnels between the dams, and the Muela hydropower station.

Further, the DWA reports that it is taking action to curtail water pollution around the country. DWA acting director-general Nobu Ngele says that there are a number of gaps in water pollution control, necessi- tating an integrated approach to tackle the associated problems.

The DWA aims to increase enforcement of the licensing conditions for mines surrounding catchment areas, enforce blue and green drop standard compliance by all municipalities in the country and implement remediation plans in affected water bodies.

One such water body receiving rehabilitation is the Hartbeespoort dam, in the North West province. Ngele reports that the DWA, in conjunction with other local stakeholders, such as the Madibeng local municipality, has implemented the Harties Metsi Ame remediation plan.

This rehabilitation scheme had to be implemented following, besides other factors, the uncontrolled dumping of raw sewage from other upstream munici- palities in the Crocodile river, polluting the dam.

Interventions include the re-establish- ment of the natural ecological processes in the dam, by reducing the numbers of exotic fish, such as carp and barbel. Further, rehabilitation work is focusing on re-establishing natural shoreline and wetland conditions for species to thrive. Algae and hyacinths are also being biologi- cally and mechanically harvested. “Two ongoing ecological surveys point to the composition of fish already improving,” Ngele says.

She adds that the DWA has allocated R27-million for a bulk water project in the Madibeng local municipality to expand the local wastewater treatment works in order to meet current and future demand.

Meanwhile, government is in the throes of establishing a long-term solution to the rising-acid-water challenge in the Witwatersrand area. Minister of Water and Environmental Affairs Buyelwa Sonjica says that Cabinet has appointed an inter-Ministerial committee to deal with the challenges of AMD.

“The committee has decided on a way forward to solve the problem. This includes appointing a team of experts to assess the risks involved in the raising levels of acidic water. “The team has also been mandated to assess what various institutions have already done, as well as to look at available technologies to remedy the situation,” the Minister says in a statement.

The team of experts is currently assessing the viability and costs involved in implementing critical short-term interventions to extract and purify the AMD. This must be done to prevent rising acidic groundwater from decanting in the central Johannesburg basin.

The Minister says that an urgent solu- tion is needed, owing to AMD having already reached the surface in the Western basin. While immediate actions are being sought to deal with the problem, the drawing up of an integrated medium- to long-term solution strategy is also taking place.

Edited by: Brindaveni Naidoo Written by Henry Lazenby
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