The Green Drop Report 2022 which has been released after nine years since the first report in 2013 indicates a decline in South Africa’s municipal sewer treatment systems. It indicates that only a few sewer treatment plants are fully compliant in that they can effectively treat wastewater to discharge clean water. The most prominent risks highlighted are that the treatment plants often exceeded their design capacity, had dysfunctional processes, ineffective disinfection equipment, poor flow monitoring devices, and were generally non-compliant in treating sewage and sludge. The country’s largest cities have an increased risk of overflowing sewage pumps thus discharging raw or partially treated sewage into rivers throughout the country, turning dams green and killing the people who drink the polluted water.

National Green Drop Report 2022 – Download Report

What’s more concerning is that some municipalities are increasingly growing incapable of addressing issues of wastewater management due to a lack of human resource capacity – competent and experienced technical staff as well as due to restricted budgets for maintenance. The pollution of the Vaal River and issues of wastewater overflowing on the streets of Dunoon township in Cape Town give an indication of this. The global best practice is for municipalities to spend 15% of the value of a plant on its maintenance but maintenance budgets are often where corruption is prevalent. According to a report from treasury only 1% is spent on maintenance.

As with the overdemand crisis situations that the country is often faced with such as the ongoing energy crisis resulting in load shedding, effectively relieving the country’s sewer system requires two different approaches being to either increase supply by building more treatment plants or to decrease demand by encouraging consumers to switch to more sustainable methods. The former becomes illogical to implement due to the failure to effectively address the underlying issues of corruption however, the latter seems to be more viable with most of the country now switching to reliable and sustainable means of life such as the use of solar power and so forth.

In the sense of Water & Sanitation, a more sustainable means is to switch to a home sewer package plant. A few options for this exist but one of the most popular ones are septic systems. In rural areas where there are hardly any connections to public sewers, septic systems can be used to offer long-term sewage and environmental solutions. Ditlou Consulting Engineers was appointed by the City of Tshwane, Health and Social Development to undertake the planning, design, construction supervision, and project management for the construction of a new multi-purpose center in the Winterveldt. The development was to be constructed just outside the urban edge of the City of Tshwane Municipality where no sewer infrastructure exists.

The ideal solution for a sewer package plant implemented by Ditlou Consulting Engineers was a septic system that contains watertight septic tanks. The septic tanks were designed and constructed to receive the discharge of sewage from the center to store it for a detention period that provides separation of solids from liquids and digestion of organic matter. The liquids are then discharged as effluent into succeeding tanks which are the bioreactor and chlorinator tanks that provide further chemical processes to ensure that the effluent to be discharged to the environment is of acceptable quality as per the Greywater Specifications under the Department of Water & Sanitation as well as the Department of Water Affairs and Forestry.

Rigorous design considerations from the consulting firm as well as making use of reputable sewer septic system service providers to install and maintain the plant become key elements that play a vital role to ensure that the package plant is constructed to be compliant. Reputable sewer septic system service providers that are SANS accredited provide the assurance that the plant will treat the sewer and release water of acceptable quality and can ensure that the plant is maintained as it should with regular tests done on the water.

Subsoil Drainage & Flo-Drain Layout Drawing designed by Ditlou Consulting Engineers

Other septic systems are designed in a special way to ensure solids will settle to the bottom and the water is released into a soak away where the surrounding soils will have desired characteristics that further filters the effluent so that the plumes that get into contact with the underground water do not contain harmful contaminants. Soils contain microbes that are helpful in purifying the effluent by retaining harmful pathogens and bacteria. There are more microbes in a teaspoon than there are people on Earth and thus soils with desired properties will provide naturally occurring processes to filter the effluent and thus provide an eco-friendlier option.

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