Cold Link Africa March/April 2018 | Page 25

EVENTS AND EXHIBITIONS INCORPORATING COLD CHAIN De Lille gave some insight into the measures taken to reduce water wastage. “At the beginning of 2017, the water usage was 1 000 million litres a day and needed to be halved. The City has employed 4 000 additional people just to attend to leaks in the city and we are engaging with the agricultural sector to reduce their consumption. The holiday season with the many tourists coming into Cape Town could increase consumption by 1% but fortunately, it is also the time when industry and the builders close and this will help to offset the increase.” De Lille concluded with a clear message: “It is no good blaming the ills of the past as it will not help the present or the future. We all need to stand together and for our own good, tackle the water shortage head on. Cape Town has the lowest level of unemployment in South Africa because of partnerships with business. With the same approach we will not let the taps run dry.” Speakers all referred to the critical period as March 2018 when the present storage will be depleted, but hopefully, this will intersect with the new rainfall season and the effects of initiatives to find alternative supplies. (Ed.’s note: This has since been adjusted to May 2018.) Pressure measurement zones have been identified and pressure-limiting devices have been installed, according to De Lille. NOT ALL WATER IS EQUAL Peter Flower, director of the Water and Sanitation Department of the City of Cape Town, addressed various issues relating to water and the quality thereof. It was interesting to note that there is a much wider use of treated effluent water for irrigation, earthworks, and construction sites around Cape Town. However, Flower warned everyone that this water should not be used for mixing cement/concrete as it could have an impact on the strength of the concrete. He also addressed the issue of the impact of reduced water pressure on The forum, which took place in Cape Town, was well attended. firefighting. He emphasised that the City has a responsibility to provide potable water to all its citizens, but does not have an obligation regarding the pressure at which it is supplied. Therefore, users should make their own arrangements for having the required pressures for fighting fires. He also strongly recommended that users discuss this matter with their risk assessors. Flower made an interesting comparison about desalination plants and feeding water into the network from around the coast. He likened it to a hand: Our central water supply comes from the inland dams (palm of the hand) and then gets supplied to users at the coast (end of the fingertips). If we now start producing water at the coast and start pushing it back into the system to feed users further from the coast, we will require changes to our piping and pumping infrastructure. The pipes that start at the dams are very large and those feeding areas at the coast are much smaller. If the main source of water is at the coast, we will need to make the necessary changes, which are not that easy in the very short term. Although there was a lot of discussion about desalination, everyone was reminded that it is like a double-edged sword, as it uses a lot of energy and is responsible for a lot of carbon emissions, too. Flower also spoke about what he referred to as ‘delinquent users’ — people who have ignored all appeals to cut back on their water usage. He said that he hoped that as the situation deteriorates further, the delinquents would do something about changing their wastage habits. He acknowledged that the City itself was faced with many challenges and was employing a wide variety of initiatives to address the problem, especially in lieu of the fact that they had 11 000km of pipework to service and maintain. Every detail is being considered. As an example, all fire tenders are kept full at all times with treated grey water. Pressure-limiting devices have been installed in the supply to areas that can cope with reduced water pressures during certain periods. It was interesting to note the comments about water footprints — how much water is needed to produce our food? People COLD LINK AFRICA • March | April 2018 The signed pledge by the Cape Town members of FEDHASA to reduce water consumption, was presented by Jeff Rosenberg, Cape chairperson. www.coldlinkafrica.co.za 25