Durban -
Durban could face more than a decade of water shortages and restrictions unless the city took a political decision to pursue the controversial “toilet-to-tap” drinking water reclamation proposal, water and sanitation chief Neil Macleod warned.
The proposal, which involves using sophisticated treatment plants to purify sewage effluent to a safe drinking quality standard, has stalled because of a petition by more than 13 000 objectors, including many Islamic residents.
Macleod has suggested that a new study be done to examine religious-based objections to the concept of re-using sewage water. This could guide future decisions on sewage effluent purification.
He warned that the city was running out of water fast - despite the recent completion of the Spring Grove dam near Mooi River - and faced some tough choices on how to avert a potential water shortage and sewage disposal crisis.
While the newly-built Spring Grove dam was expected to fill within months, the growing demand for water would exceed this new capacity within two years. This meant water restrictions would become “inevitable” if KwaZulu-Natal had poor rain.
There was also a feasibility study under way to build a giant new dam on the uMkhomazi River (formerly Umkomaas River) but, even if this went ahead, it was unlikely that it could supply any water before 2030 - at the earliest.
Another option was to build desalination plants to purify salt water from the sea, but this was expected to cost double the current Umgeni Water tariff.
Because desalination required large volumes of electricity, it was also unlikely that Eskom could supply enough electricity for desalination because of the current national power shortage.
Another problem was that the volume of effluent from the eThekwini region was increasing so fast that, if more sewage was to be dumped into the sea via new offshore pipelines, this could compromise the city’s ability to extract relatively unpolluted sea water for desalination.
The Department of Water Affairs had also launched a new study into the increasing degradation of Durban’s river estuaries by growing levels of sewage effluent.
It was possible for Durban to consider releasing more semi-treated sewage effluent into selected rivers, but this would mean they would become sacrificial “work-horse” river systems, and the national department was already worried this would lead to unacceptable environmental pollution.
“All the development plans of the city are dependent on a solution being found for both an assured water supply and a functional means for the disposal of treated sewage effluent.
“For priority development initiatives to be able to continue, key decisions will have to be made within the next 12 months to both safeguard the future of water supply to eThekwini and to facilitate authorisations for the expansion of sewage disposal facilities,” Macleod warned in a report to the city’s human settlements and infrastructure committee.
The report was written almost six months ago, but has been tabled and deferred twice by the committee.
Last month, city manager S’bu Sithole recommended that discussion on the report be referred to political party caucuses for comments and input, but discussion was deferred again this week when it came before the human settlements committee.
Nevertheless, Macleod cautioned that water supply and environmentally-sound sewage disposal services were now “at risk” and there was an urgent need to find solutions.
Unless water supply was augmented by desalination or effluent re-use, the region would “experience water shortages” from around 2018 and this would last till at least 2030, assuming the dam on the uMkhomazi River was built. As such, it was crucial the eThekwini Municipality make a final decision before June/July.
Late last year, Overport resident Yunus Shaik and the Concerned Citizens Campaign collected more than 13 500 signatures against the proposed Durban project. He had no objection to recycling sewage effluent for industrial use. - The Mercury