Integrated infrastructure delivery company AECOM senior engineer Hanine van Deventer stresses that, when a severe multiyear drought, coupled with difficult water-management parameters, is experienced, such as was the case in the Western Cape from 2015 to 2018, water-crisis conditions hold serious implications and challenges for everyone concerned.
She adds that Cape Town was faced with a dire situation when it was announced that the municipal water supply could be cut off owing to dwindling supply. However, since then, dam levels in the Western Cape have recovered significantly. While that has led to the relaxation of water restrictions, it does not entirely reassure the private sector of uninterrupted municipal water supply.
“Private-sector companies are seldom knowledgeable or equipped to deal with water-crisis interventions on a regular basis, possibly leading to an unwitting and/or hasty approach to implementing solutions.”
When faced with the daunting task of implementing infrastructure to combat an unprecedented event such as the threatened ‘Day Zero’, stakeholders can often over-, or worse, underestimate the level of intervention required, she says.
The draft Cape Town Water Strategy, published in January 2019, states: “The future is uncertain, and the cost of very severe restrictions is much higher than the cost of insuring against this likelihood by providing additional water-supply capacity.” Hence, water resilience is key.
South Africa is classified as a water-scarce country, with some projections estimating that, at present, it exploits roughly 98% of its available water-supply resources. In many areas, the water challenge is looming ever larger, notes Van Deventer.
“The ability of all stakeholders to respond wisely, lawfully and fairly in such a crisis becomes a daunting and complex minefield, especially to enterprises not knowledgeable of the requirements.”
This is where AECOM’s expertise is vital, ranging from risk assessment to mitigation of identified risks and assurance of sustainability, she adds.
During the Cape Town crisis, AECOM was approached by various private companies to provide professional services that would improve their resilience in response to water-supply interruptions, says Van Deventer.
This was driven largely by commercial interests such as loss of revenue, liability concerns in terms of safety and insurance requirements. Other drivers were the long-term goals of reduced utility costs or ultimate independence from the municipal water supply.
“Some clients noticed the impending crisis, requested budgets, and engaged early. Some were more structured, but many left these interventions too late, and were required to respond to all these critical concerns simulaneously to manage the immediate and evident crisis,” she points out.
The emergency solutions and mitigations ranged from fairly innovative to more radical measures that were “sometimes inadequate, high-risk and beyond the legislative framework”. Water-saving initiatives included replacement of conventional sanitary fittings with water-saving technology. Here the problem is not only understanding what this technology actually is, but what it can achieve, Van Deventer says.
She states that companies also looked at various other methods to save water and/or reduce water use, including altering air-conditioning systems, introducing dual-plumbing water systems and the addition of fire extinguishers to supplement water-suppression. Supplementary water sources were also investigated. These included rain- and grey-water harvesting, reclaimed groundwater harvesting – collection of seepage groundwater or borehole water – blackwater and greywater treatment, potable water tanker supply and use of bottled drinking water.
She adds that the options of encouraging employees to work from home to avoid business disruption and supplying them with imported water instead of having to queue during working hours, thus alleviating the inconvenience, were also considered.
Van Deventer refers to a recent paper written by herself, AECOM associate engineer Kondrad Kohrs and AECOM candidate civil engineer Belinda Herbst, titled ‘Improving Our State of Water Resilience: A Private Sector Perspective’ in which the authors warn that, “water is a precious commodity that needs to be managed wisely to serve the ever-growing population and promote economic growth”.
Source Article from https://www.engineeringnews.co.za/article/water-crisis-conditions-hold-serious-implications-and-challenges-2019-06-21
Water-crisis conditions hold serious implications and challenges
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