9 January 2018

  • The need to augment raw potable supplies in Cape Town, via the re-use of wastewater re-use and/or desalination interventions, was predicted as early as 1970 (i.e. 47 years ago) to be required by the year 2000 (1970 Government Commission on Water Matters). The volumetric estimates of water demand by the latter date (2000) were also predicted with unprecedented accuracy in the 1970 assessment.  While the assessment pre-dated the construction of the Theewaterskloof and Berg River impoundments, it underestimated population growth and did not consider climate change — other than to acknowledge that the ravages of drought can only be offset through planning and optimal resource utilization.
  • Estimates placed the generation of effluent at 70% of total abstraction. For Cape Town, this is an immense volume of water, continuously available for treatment and re-use – instead dumped into the nearest river or the sea.
  • Despite the aforementioned warning, both the Department of Water and Sanitation (DWS) and, in particular, the City of Cape Town (‘CoCT’), have apparently ignored same in favour of more recent reports/predictions which, ostensibly, have played down the need to take substantive preventative action to augment supplies. Despite population expansion and the burgeoning migration to the City, including thousands of economically-disadvantaged families, the CoCT chose to loosely follow a practice of ‘demand-management’.  None of the three interacting spheres of government — national, provincial or local —, however, can excuse themselves from responsibility for the extant crisis.

Read more »


18 December 2017

NMU’s Center for Coastal and Marine Research have added the bbe Moldaenke PhycoProbe to their armoury of bbe chlorophyll measuring instrumentation.  The just-released PhycoProbe adds the ability to measure unbound phycocyanin, in addition to Total Chlorophyll and that from the individual groups of cyanobacteria, green algae, diatoms and cryptophytes.  The ability to measure unbound phycocyanin provides a proxy indication of cell leakage and the possible release of algal toxins into the aquatic environment.  This technology is now also incorporated in other bbe instruments such as the PhycoSens.

Prof Renzo Perissinotto (right) and Dr Gavin Rishworth (left) with their new bbe PhycoProbe.

The bbe FluoroProbe (and more recently, the bbe BenthoTorch) has been an integral part of Professor Renzo Perissinotto’s research team for the past decade and a half.  Recent projects within Prof. Perissinotto’s Shallow Water Ecosystem (SWE) SARChI Chair have focussed on three sectors, in addition to many other subsidiary projects: (1) seasonal long-term monitoring of the dynamics of Lake St. Lucia, the largest estuarine lake system in southern Africa, (2) biological community responses and baseline monitoring of proposed hydraulic fracturing of shale gas sites in the Karoo, and (3) ecosystem drivers of living peritidal stromatolites growing along the South African coastline.  In all of these ecosystems the data from the bbe Moldaenke units have provided valuable insight into ecological dynamics. Read more »

Scientist predicts “a total system crash in March 2018” for Cape Town’s water supply

26 October 2017

The slow onset crisis unfolding in South Africa is – at least in my professional opinion – about to enter a new phase. Gauteng came within a week of running out of water last year, saved only by a major rainfall event that fell literally deep into the eleventh hour. Many think that the drought has gone away, so they no longer worry. Cape Town is now where Gauteng was over a year ago. Unless it rains in the next 4 months, then the water supply will literally collapse by March 2018.

This is very serious, so I have decided to write this piece in a sincere effort to galvanize constructive debate in the public interest.

The dataset attached shows dam levels since November 2016. Remember that the Western Cape is a winter rainfall area, so we are now out of the normal rainfall season entering the dry season with dams less than 30% full. But this only tells part of the story. The second graph shows the combined total of all dams in the Cape Town metro area since 2014 as the blue line, with useable water as the red line. Note the following:

1) Distinct seasonal cyclicity as rain falls in the winter followed by a dry summer.

2) Useable water is always less than dam levels, because of losses and other factors.

3) Each peak since 2014 has been lower than the previous peak, with a near linear downwards trend over the last three years.

4) Each trough follows a similar trend, being lower than the previous cycle.

5) The data stops in October 2017 (present date) on a high that is lower than all previous highs in this dataset, so extrapolating historic data into the future, we see a total system crash in March 2018.

This is dire. In fact, this will be the first case of total system failure in thecountry. Without water commerce is not possible. Shopping centres cannot operate if they cannot flush toilets. Banks cannot have staff on the premises if they cannot use the toilet. Schools cannot operate if children are unable to remain hydrated and flush toilets (here the proxy is a school in Port Shepstone that was forced to send pupils home for the same reason). Hotels cannot provide for guests so the tourism industry fails. Hospitals cannot function so patients need to be transported elsewhere (here the most accurate proxy indicator is the Murchison Hospital near Port Shepstone where water supplies have failed). If a high-rise building should start to burn, then there is insufficient water to extinguish the flames (here the proxy is Braamfontein a year ago).

Read more »

The Cape Town water crisis: who knew?

17 October 2017

Unless some seriously impressive rains materialise in the very near future, Cape Town is facing a socio-economic crisis of note when the water runs out.  By comparison, the ‘hardships’ of the Eskom load-shedding times will pale into insignificance as millions of residents queue for their water ration.  City officials assure us that all is under control – but many of us are unconvinced.

Water ‘resilience’ has become a new buzzword, although melding ‘resilience’ with the emergency situation that the region finds itself in is a tad odd.  But there are lots of knee-jerk reactions in the mix and placating the public is obviously a priority.  Point of fact is, however, that the need for desalination in Cape Town by around the year 2000 was foreseen 47 years ago.

Read more »

The Cape Town drought: are more supply problems just around the corner?

5 October 2017

Bloom of toxic cyanobacteria in Theewaterskloof Dam(Photo: Bill Harding, 1991)

Bloom of toxic cyanobacteria in Theewaterskloof Dam(Photo: Bill Harding, 1991)

Monitoring for blue-green algae in times of drought – a need for increased vigilance:

The continuing and very troubling, ok downright scary is what it is, drought in the Western Cape should be on the minds of all those affected.  A major metropolitan area, plus numerous municipalities, are faced with the prospect of having to provide water from tankers at street corners in the not too distant future.  Millions of people will face considerable hardship, all the while having to continue to meet their daily obligations, be it family, work, education and so on.  Many work opportunities will be lost, at least temporarily.  The shortage of water problem could also, and rapidly, become a whole lot worse should what is left of the water become undrinkable.  Not everyone can afford bottled water. Read more »

Deja vu… drought, wastewater re-use and the abandoned Athlone Power Station precinct

20 June 2017

Athlone’s towers have fallen down

[This post originally appeared in Droplets in January 2011…]

I understand that the huge building that was the Athlone Power Station is being considered for a museum of some sort?  The odds are probably quite good that it will be developed into a shopping mall.

The site is immediately opposite the long-overloaded Athlone wastewater treatment works – a works that has no space to expand to meet increasing demands.  When the cooling towers came down, I suggested (to the City) that it would be a good idea to fill the building with reverse osmosis water purification modules and treat the otherwise ghastly final effluent (see how the City responded here) to a useable, and saleable, quality (RO can achieve potable quality).  This, to my mind, would be a logical and strategic use of space.  There is already a pipeline from the works underneath the N2, as the effluent was used as cooling water for the towers.

The concept of converting waste, in this case wastewater effluent, into an asset (irrigation, drinking or industrial water) is not taking root in South Africa – but it needs to!  This approach would also allow recovery of the appropriately-named Black River from its present role as a wastewater drain.”

I have no doubt that my original idea is likely to be fraught with technical and perhaps economic challenges, but none so challenging as having no water at all!  The City subsequently (in July 2011) announced that the quality of Athlone effluent had improved substantially between 1998 and 2011 – a claim that I cannot confirm or deny as I have not seen any empirical proof thereof – but it does suggest that the proposed water quality treatment or pre-treatment would now be easier than I previously envisaged.

The City of Cape Town produces a lot of wastewater effluent every day – polluting the rivers and the marine environment on a continuous basis.  And, yes, the production of wastewater (and the disposal thereof) is an inevitable fact associated with human life and especially with large metropolitan areas.  Equally true is that the polluting impact of this wastewater can be  attenuated at or near source (= at or near the wastewater treatment works) into a product that is substantially less harmful to the environment, as well as being a revenue-earning commodity.

At the very least, the empty halls of the Athlone Power Station still provide a site for a decent pilot study.


Thames Water ordered to pay record £20 million for river pollution

31 March 2017

Thames Water Utilities Ltd sentenced in the largest freshwater pollution case ever taken by the Environment Agency

(Press Release First published:22 March 2017).

Read more »

Sewage “spilling continuously” into Butterworth river (South Africa)

31 March 2017

Residents and livestock suffer while year-old leak is unfixed

(Droplets comment: readers of this sad story might be interested in the one that follows it…)


Photo of bridge and dirty river
Sewage has been leaking into the Gcuwa River near Butterworth for more than a year. Photo: Mbulelo Sisulu

Sewage has been leaking into the Gcuwa River near Butterworth for more than a year, after damage to the pump mechanism caused by illegal electricity connections.

Amathole District Municipality spokesperson Siyabulela Makunga confirmed that two sewage pump stations in Butterworth were “spilling continuously” into the river.

According to Makunga “the community have connected illegally to the incoming electricity supply, damaging the cables and pumps”. Eskom had agreed to move the transformer at one of the pump stations, but had not done so.

But Eastern Cape Eskom spokesperson Ntombekhaya Mafumbatha said she did not have evidence that the municipality had reported the problem. “Leaking sewage is urgent and needs to be fixed very quickly because it affects many things,” she said.

The leakage started at the beginning of 2016. Residents say the matter was reported to the councillor, but nothing was done.

Read more »

SA’s Drinking Water Reservoirs are full of shit. Literally

30 September 2016

(Guest post by Graham Sell – republished with permission – emphasis added)

It was only when I started looking into the controversial award of a Water Use Licence (WUL) to Metsimaholo Municipality (enabling them to pump treated and partially-treated effluent from their Refengkgotso sewerage works into the Vaal Dam at Deneysville) that I realised how deeply in the pooh we are across the whole country – both literally as well as metaphorically.

Before getting back to the specifics of the Refengkgotso pipeline, take a look at the compliance table below to see how your province fares in the Green Drop stakes. The Department of Water Affairs and Sanitation (DWS) Green Drop awards program sets standards for processing raw sewage into an acceptable state for reintroduction into the environment.  As a cornerstone of the program, municipalities are required to regularly test the effluent from their waste water treatment plants to ensure that it complies with prescribed microbiological, chemical, and physical standards.

Read more »

Convention on monitoring of ship ballast water nears ratification – bbe technology ready

20 May 2016

International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM)

Invasive aquatic species present a major threat to the marine ecosystems, and shipping has been identified as a major pathway for introducing species to new environments. The problem increased as trade and traffic volume expanded over the last few decades, and in particular with the introduction of steel hulls, allowing vessels to use water instead of solid materials as ballast. The effects of the introduction of new species have in many areas of the world been devastating. Quantitative data show the rate of bio-invasions is continuing to increase at an alarming rate. As the volumes of seaborne trade continue overall to increase, the problem may not yet have reached its peak.

However, the Ballast Water Management Convention, adopted in 2004, aims to prevent the spread of harmful aquatic organisms  from one region to another, by establishing standards and procedures for the management and control of ships’ ballast water and sediments

Under the Convention, all ships in international traffic are required to manage their ballast water and sediments to a certain standard, according to a ship-specific ballast water management plan. All ships will also have to carry a ballast water record book and an international ballast water management certificate. The ballast water management standards will be phased in over a period of time. As an intermediate solution, ships should exchange ballast water mid-ocean. However, eventually most ships will need to install an on-board ballast water treatment system.
bbe’s BWM technology at the forefront of monitoring solutions

In a recent test of BWM technologies, bbe’s “10 cells” proved to be the world leader: Read more »