DECENTRALISED SOLUTIONS: THE ANSWER TO SOUTH AFRICA’S WATER CRISIS

South Africa is currently facing the perfect storm of a failing water supply: outdated infrastructure, poor maintenance, prolonged droughts, increasing population, lack of investment, and a skills shortage have led to contaminated drinking water, raw sewage spewing into rivers, and run-down water treatment plants reminiscent of an apocalyptic movie.

By Chris Ashmore, CEO, Watericon

Achilling warning sign is the 31 people confirmed dead from a cholera outbreak in Hammanskraal, where Watericon subsequently installed a water treatment plant at a school that did not have access to safe, clean drinking water – considered a human right by our Constitution.

The South African government’s latest Blue Drop Report, which assesses the state of all drinking water systems across the country, reveals an alarming decline in water quality and management. Roughly half the sites assessed failed to meet acceptable biological and chemical standards with regard to drinking water. Further:

• 23% of municipalities were ranked as being at critical risk

• 56% wastewater treatment works are not functioning properly

• 60% of systems do not comply with microbiological standards, and 77% flunked the chemical treatment requirements.

The Green Drop Report, which assesses the country’s wastewater systems, found that one in three wastewater treatment plants was considered in critical condition. An expose by the amaBhungane Centre for Investigative Journalism found that many have been completely abandoned or vandalised, leaving raw sewage polluting our water systems, including the Vaal Dam, which supplies water to around 19 million people.

Centralised vs decentralised solutions

A centralised solution is a large-scale water treatment plant servicing surrounding areas. These plants have the capacity to process enormous volumes of water, while the transport of water to and from the facility occurs via an expansive distribution network.

The main advantage of centralised systems is the efficiencies gained through economies of scale. They are commonly used in developed nations all over the world, and in South Africa for municipal water supply.

However, there are several disadvantages of this type of system:

• The distribution network is complex and costly.

• Large capital investments are needed for facility upgrades

• Operating and servicing costs are high.

• Highly skilled technical expertise is required to manage the plant.

• It is difficult to measure and record upstream and downstream water quality because of the vast piping system.

Decentralised approach

A decentralised approach involves smaller-scale water treatment solutions that are applied directly to individual facilities or communities. They typically consist of modular units or packaged plants that are mobile.

They have several advantages:

• The plants are designed and tailored for one specific application on-site.

• Water reuse and wastewater reticulation are easier, as water does not have to be piped across vast distances.

• Capital costs for setup are much lower, as are the lead times.

• They can be scaled up or down at any time.

• Modular units are mobile and can be easily transported from site to site where needed.

• Their small footprint means much less space is needed.

For example, at Capricorn College in Limpopo, a plant we designed and installed treats borehole water to be used as drinking water by the community of over 1 000 people. The equipment is also used for chemical engineering students to learn how to operate the plant.

Small footprint, big impact Mauritius recently turned to a decentralised solution to produce clean drinking water. Although the island has access to seawater, desalination plants are costly. Luckily, the island also has abundant rainfall, as well as 11 self-contained units that treat captured rainwater to drinking water standards and currently supply 260 000 residents.

New property developments in Mauritius must include their own water supply. Watericon recently installed a decentralised plant that will be scaled to produce 45 m3/h of treated water to service 5 000 to 10 000 people in a residential development. We predict

South Africa will soon be going this route, where any new buildings or resorts will need to generate their own power and water supply.

Mines in far-flung places are also regular users of decentralised solutions. At one such mine in the DRC, the camp and surrounding community had no option but to drink polluted water from the river, causing people to fall ill. Just two 20-foot containers purified this water, supplying drinking water to over 50 000 people. At another mine in South Africa, we built two 20-foot containers to treat sewage water to produce effluent in line with local regulations. The effluent is currently being used for irrigation by nearby farms.

Reduce, reuse, recycle Companies can turn to decentralised solutions to reuse and recycle water. A local automotive plant was able to save around 21 million litres of water a year by treating their effluent to be reused in the system. This made them less reliant on municipal water for processes like rinsing paint, while minimising their environmental footprint.

With any water treatment plant, it’s vital to understand upfront what the water balance is. How much water is coming in? How much waste will be generated? The goal is to reuse and recycle as much as possible. This means understanding the regulations, and what is stated on the company’s water use licence.

The importance of operations and maintenance

Similar to servicing a vehicle, a water treatment plant needs to be maintained to increase its lifespan and make sure it functions optimally and safely. With any water system, it’s crucial to create a blueprint for operations and maintenance (O&M). This is where many municipalities are falling short.

The Green Drop Report found there is no monitoring in place at many of the wastewater treatment plants, equipment is broken, and no records exist for the water systems. According to the report, a run-to-failure strategy is allowed without any apparent intervention from municipal leadership.

Among these is the Gariep Dam wastewater treatment plant. One of the plant's pump stations has been broken for two years, and is discharging raw sewage into the adjacent nature reserve.

The nine-year gap in Green Drop assessments allowed several functional plants to reach a state of total collapse. A run-to-failure approach is not a good strategy, unless the system is very basic and there are no safety risks – but certainly not for the complex systems of a centralised solution.

Often, water testing isn’t done regularly enough, or samples are not being sent to accredited labs. It is essential to test water quality entering homes on a frequent basis to ensure that it has not been contaminated by septic tanks or other sources of disease via leaking pipes. But the vast piping network of centralised solutions makes regular testing a costly and complex task.

Preventative and predictive maintenance

Preventative maintenance involves consistent monitoring and servicing on a weekly or monthly basis. It does not need advanced expertise, just competent technicians who are trained to measure indicators and test water.

With innovations in technology, there is also the option to monitor plants remotely. Predictive maintenance can be used for more advanced systems. It is more costly initially, and requires a higher level of skills, but timely and informed monitoring can prevent breakdowns. Each asset in the system should be barcoded and entered into a reporting system like Sage, or even an Excel spreadsheet. It is possible to track a small bolt from its purchase to endlife. By following trends and patterns in the data, it’s possible to spot where and when a breakdown is likely to occur.

When running a water treatment plant, it is important to ask the following questions:

• Who is going to maintain the plant?

• Does this need to be outsourced?

• Is a safety officer required?

• Does there need to be full-time staff on-site?

• Is it necessary to have a laboratory on-site for monitoring?

At some plants we have installed, there is a full team of people running it – from operators to mechanics and technicians – working in shifts to ensure equipment is working optimally. They regularly test and monitor water, and implement preventative maintenance with schedules, job cards, inspections, and audits.

Training is crucial. Technicians need to know their instruments, what they are measuring, as well as the physical, chemical, and biological components.

Conclusion

The Blue and Green Drop reports have highlighted the many challenges facing our water sector; however, unless regulations are enforced, not much will change.

With willingness from government to decentralise some of our water infrastructure, combined with private sector investment in skills training and capital expenditure, South Africa can ensure our communities aren’t left in the ‘poop’.