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Onsite Sewage treatment plants - The Cape fiasco

The Cape Town council's authoritative approach to wastewater management, claiming exclusive and absolute ownership of all wastewater, is not only restrictive but also costly for the ratepayers and developers.

Disregarding the importance of onsite sewage treatment plants, their insistence on upgrading their own wastewater treatment works (WWTW) to accommodate all wastewater inflows has resulted in a significant financial burden on developers, the community, and an infrastructural fiasco.

 

Water shortage and formal sewage systems - Municipal WWTW

Western Cape's water worries will only get worse. There are more people than water resources - and it is getting desperate. We all know what happens when there is less to drink, but what happens to the formal municipal sewerage systems - the pipes, pump stations, waste water treatment works - WWTW?

It is a fact that to get sewage to flow through pipes and pumps, you need at least 70% liquid. No sewer pumps handle solids only. It just does not flow. When households are restricted to 300 litres per day, there is insufficient liquid for the pipes and pumps. We mentioned this a while back in our blog on Scottburgh (Scottburgh's Gift Horse). Blockages occur everywhere, municipal pump stations and manholes overflow, and even the vacuum tanker (aptly described as a honey sucker) cannot operate. Blockages become a manual effort, and that is not a pretty sight.

 

Onsite sewage systems - Quality assurance

The option of temporary package plants are now offered as lifelines to new developments, some of which already had council approval. However, onsite sewage systems do not have a great reputation, since there is no quality assurance method of sifting out the poop from the porridge. You will only know soon after the lawn has grown back, and even then you wont say anything, because no-one brags about the stinky stuff.

A more proactive and sustainable solution would have been to develop and promote a grading system for various manufacturers of onsite sewage treatment plants (OSTPs). This approach would allow for the testing, approval and certification of different OSTPs based on their effectiveness and environmental impact. By encouraging the use of approved OSTPs, the council could have decentralized wastewater treatment, reducing the strain on centralized systems and promoting treated wastewater reuse at source. Furthermore, those few suppliers that proved compliance beyond doubt, would have been highly motivated to keep their systems running effectively. 

Day Zero would have been avoided long before Day Tomorrow.

 Sewage in the drinking water

Sewage in the Drinking Water - Noseweek

 

Compliance Certification

We felt that City of Cape Town would have seen the opportunity to start a compliance process of certification of the many systems, somewhat like the Umgeni Water / Water Research Commission program - (see here) did way back in 2006. Nothing really came out of that process, and would presume the results did not achieve the desired quality for all the systems under test. Perhaps, the taste of failure was sweetened by non-disclosure.

 And, seeing that CoCT were such progressives, their pioneering of a full live test SABS type accreditation would certainly offer all those who are forced to purchase and install a system, some comfort knowing they are less likely to be a dud.  The general thoughts are that Cape Town administrators want to avoid onsite systems at all costs.

Compliant onsite sewage treatment plants offer some important benefits, including:

 

  • Water Reuse: OSTPs treat wastewater to a high standard, making it suitable for non-potable uses such as irrigation, toilet flushing, and washing. Also, the treated water could be used to flush out blocked sewer lined that become clogged due to low water usage. (see Scottburgh above)

 

  • Reduced Impact on Infrastructure: By treating wastewater at the source, OSTPs reduce the load on centralized wastewater treatment plants, extending their lifespan and reducing the need for costly upgrades

 

  • Environmental Protection: OSTPs can reduce the discharge of untreated or poorly treated wastewater into the environment, protecting water bodies from pollution and promoting ecosystem health.

 

  • Cost-Effectiveness: In many cases, installing and maintaining an OSTP can be more cost-effective than connecting to a centralized sewerage system, especially in rural or remote areas.

 

  • Flexibility and Scalability: OSTPs come in various sizes and configurations, making them suitable for a wide range of applications, from single households to large commercial developments.

 

  • Adding Value : The owners  of these systems, and the residents in general would become eco-conscious of the negative effects of abuse, which is often metered out to the councils sewerage systems. Furthermore, the property would be seen to have added value, a great selling point, but, only if the plant performs. Nobody brags about their stinky sewage.

 

Cape Town city council are obviously aware that for them to promote the widespread use of these systems, would bear some responsibility for failures. We wrote an article on this same subject (see snake oil salesmen here) a while back, in which Durban Metro promoted the use of the on-site, privately owned sewage systems, where many failed,  and we fully understand the reluctance to go the same route. In this case, Head of Water and Sanitation - Neil McCleod - took two suppliers word as gospel, but they turned out to be rogues.

 

Stalled Developments

All the new developments, either planned or approved , were instructed that the projects were now on hold, until such time as the upgrading of the municipal WWTW were complete. Since there is a backlog of housing, prices of new and rental units have sky rocketed. Stalled developments are now costly and inflationary, and hugely frustrating.

Vacant dwellings are rare indeed.

This pushes residents away, and will now live further from their place of work. Roads are already congested and this does not help. When there are more vacant jobs than vacant homes, there is uncontrolled semi-gration, with the poorer areas becoming the most affected.  It is these areas that need full waterborne sewerage systems. Any further infrastructure must focus here, knowing that the formal and affluent areas will pay for it. They always do.

When council finally conceded to allow package plants, it came with a major condition. Once the upgrades to the municipal WWTW were complete, the plant would be decommissioned, and sewage would then discharge into the council’s new sewerage system. The fact that developers would have spent millions on providing their own systems, is of little concern, and even less compensation.

Compensation - CoCT have generously agreed not to charge for sewage disposal in the property rates account each month, during this time. After all, you cannot legally charge for a service you don't give, right?

Further developer costs included the building plans would need to return to the approval office for further adjustment to allow sufficient free space to accommodate the sewage system. In most instances, this space could not be re-allocated for building homes after councils connection.  And anyway, the developer would have left site long before the plant is decommissioned, and no-one ever wants to live on top of an old sewage system.

Secondhand sewage system

Could the second hand sewage system be resold onto another project? Not likely, since every system is designed for a specific duty, and one size does not fit all. A lot can be learned from the Durban Metro fiasco where a temporary system was installed at the La Domaine retirement village in Hillcrest KZN. This system replaced the first plant mentioned here, and No.2 would last less than 3 years, by then a privately funded Fisher Road activated sludge plant was completed. Once the Fisher Road system was fully operational, the package plant was removed to a builders yard in the area, where it stood for about 10 years, without a buyer. It is understood that it was finally parted out, and therefore lost a great deal of value. These items are not resell-able, and the tanks can never be used for potable water storage. Pretty much useless.

Based on their own performance, the hypocrisy is certainly showing. There are CoCT owned waste water systems that have discharged untreated wastewater directly out to sea in False Bay / Hout Bay, for many years. This is well documented. Cape Town council simply do not have the capacity to deal with the huge influx of new residents, but are too arrogant to admit it.

A grading system for OSTPs could have been a more cost-effective and sustainable approach for the Cape Town council, promoting decentralized wastewater treatment and on-site water reuse while reducing the strain on centralized infrastructure. This grading program has never been done before in South Africa, and would have promoted City of Cape Town into a worldwide leading authority within this growing industry. A package plant hub of Africa, perhaps?

 

SABS quality assurance

We conducted a poll on Linked-in, asking how many package plants were SABS approved. A staggering 93% thought there was SABS quality assurance specific to onsite sewage treatment plants.

SABS don't have criteria for testing, and probably wont ever go this route. Question here is why there is a perception of national compliance certification?  Are suppliers claiming this?  If so, what else are they feeding you that is also not true?

 

sabs package plant poll Linkedin Poll - What people think about SABS approved package plants

 

Instead, Cape Town authorities suggest that any system will be approved without any accreditation, and the 40 odd South African suppliers would be lining up for their piece of the pie. Some may even claim SABS accreditation.  Performance would not matter to most of them, since there would be a guaranteed “end of contract” term, and they could happily walk away from the product.

It was never intended to last, or perform.

So, for the 3 or 4 years of municipal WWTW upgrades, CoCT would turn a blind eye to the PPPP (package plant performance problem). The few really great systems out there would find it difficult to convince the developers to install a system that will perform, based on price alone. And so, in all likelihood, substandard and defective products will be in high demand. The sad thing is that Cape Town council knows this, believing it is only a temporary nuisance, and, at someone else's cost. 

Missed opportunities. Saving water - why is it so difficult?

They really CoCT this one up.

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