Water, Sewage & Effluent May June 2019 - Page 31

Africa, in 2019, we can’t afford to allow the best to be the enemy of the good. How many more people would have safe water if we could concentrate on simple things, like making sure that all water supply is chlorinated? Jobs and economic development would just be the cherry on the top. This was demonstrated nicely by what happened after Beira. The chlorine generator manufacturers got some valuable real-world application experience and were early entrants into the saltwater swimming pool disinfection business! So, a final lesson is that an opportunity taken often leads to others. It’s a culture that we need to rediscover in South Africa and where better than in the safe water business?  Mike Muller is a visiting adjunct professor at the Wits School of Governance. A former DG of Water Affairs and commissioner of the National Planning Commission, he now advises on water and development matters as a member of the Strategic Advisory Group of the UN’s Joint Monitoring Programme for the water supply and sanitation components of SDG6. www.waterafrica.co.za Water Sewage & Effluent May/June 2019 29 About the author innovations contractor and protect them from the pressures to employ unsuitable relatives, friends and local residents for complex tasks. By this stage, many engineers just want to get the job finished; they are not going to add operation and maintenance worries to their to-do lists. Yet, if we build simple and robust equipment, it will work better and last longer. And if we design processes that use local products and can be operated by relatively unskilled workers, we are supporting the local community and the economy more generally. In any area of business, there will always be a ‘better’ product. And certainly, in the world of water treatment generally, and disinfection in particular, there are many alternatives. But in South The recent Cyclone Idai devastated Mozambique, with dire consequences to infrastructure. They even funded a small engineering company to build a prototype and transport it to Beira. It worked! We mixed up 1 000ℓ of salt solution in the morning, ran the system for four or five hours and that afternoon we had 1 000ℓ of hypochlorite solution, enough to re-chlorinate the water for 250 000 people. It was too good to be true – for a month or two. The advantage of the on- site process was that the hypochlorite solution could be dosed straight into the discharge from the reservoirs – if you try and store it and transport it, it rapidly loses strength. However, the problem is that hypochlorite solution, like chlorine gas, is corrosive. In our chlorine generator, the electrolytic cell and pump were made of corrosion resistant stainless steel (and the catalyst was platinum-based). But the rest of the plumbing and electrics was vulnerable, and we soon began to have problems. After a month or so, the experiment was over. We could generate chlorine locally, but the equipment would have to be completely re-specified to be more corrosion resistant. That experience taught me some useful lessons. Building new water systems in South Africa is often a thankless task. Firstly, explain to politicians what is proposed and why. Then identify suppliers who can produce and deliver the right kind of equipment at the right time while jumping through the procurement hoops to justify the selection. Then go through another set of procurement processes to get a