Sewage Contamination

Time to fix YOUR own water!

If you consider that all sewage treatment systems in South Africa eventually decant into a natural water course, one will hope that the effluent generated by these facilities has minimal impact on downstream water quality. Inevitably, the surface water reserves used for drinking water accept sewage effluent at some point in the upstream water course. It’s essential that the inputs into these surface water systems illicit the lowest levels of water quality change possible.

Sadly, in South Africa 52 % of our sewage treatment works fall into risk categories, as per the Green Drop Report, released last year. Sewage works are discharging inadequately treated sewage effluent into water courses that may eventually become the source water for our bulk drinking water treatment systems.

Release of poorly treated sewage into the environment has the following effects:

  • Increased levels of organic matter: Sewage effluent contains a high amount of organic matter, which can cause an increase in the level of biological oxygen demand (BOD) downstream. If the downstream water treatment plant is not designed to handle such high levels of BOD, it can lead to decreased efficiency in treatment and potential issues with taste and odour.
  • Pathogens and bacteria: Sewage effluent can contain a variety of harmful bacteria and pathogens such as E. coli, viruses, and protozoa. If these contaminants are not adequately removed downstream, it can lead to health concerns for those consuming the water.
  • Nutrient pollution: Sewage effluent also contains high levels of nutrients such as nitrogen and phosphorus. If not properly treated downstream, these nutrients can lead to an overgrowth of algae and other aquatic plants, which can cause taste and odour issues, harm aquatic life, and create aesthetic concerns.
  • Increased treatment costs: Treating poorly treated sewage effluent downstream can be costly, as it often requires additional chemicals and equipment to remove contaminants and ensure that the water meets safe drinking water standards.

In general, our bulk water treatment systems are not equipped with the treatment processes required to handle sewage effluent inputs. These contaminants pass, either partially or completely, untreated to the bulk drinking water supplies.

Gastrointestinal illnesses are the most likely the result of drinking contaminated water and are controlled though disinfection of the bulk water supply with chlorine or chloramine. For the most part, this disinfection should protect consumers from disease, however, with the routine loadshedding currently being experienced in South Africa, there is no guarantee that adequate disinfection is taking place.

It is time for even the less discerning water consumer to consider the quality of their drinking water and implement safeguards against the widespread effects of South Africa’s failing infrastructure.

If your company is responsible for proving safe drinking water to end users, or if you are a concerned citizen, and would like to take control of the quality of water being supplied for potable use, please reach out to the BWT Africa engineering team. We will work with you in selecting a suitably engineered solution or products to ensure your drinking water is safe for consumption.