Our article “Environmental management needs to be democratised” invites City of Cape Town water officials to further research the complex ecology of effluent entering the Kuils River, to understand why microbial pollutants are building up to hazardous levels in the mud and water.

We point out that current City water quality data is neither publicly available nor peer-reviewed. Instead of responding to the reasoned questions we pose about why a premier independent water quality laboratory in Cape Town could find such high levels of E.coli and Enterococcus, the City has chosen to use its Right of Reply to attack our integrity as scientists.

The claim that we have been alarmists who caused panic in the media is false.

Our concerns about algal blooms were raised not in the media, but by telephone and email to the Western Cape Department of Environmental Affairs and Development Planning after analysis of satellite data from a fellow scientist suggested that blooms were a toxic variety. We requested an urgent on-the-ground investigation to confirm the satellite image analysis.

The emails noted a link between harmful algal blooms and possible marine mortalities. To imply we prophesied mass deaths — by implication, human — is fallacious.

The Cape Argus article claiming cholera on the beaches was retracted, corrected and republished in full by Independent Media, acknowledging that its staff had erred.

Within hours of the Cape Argus “cholera” claim, we arranged for UCT Media and Communications to issue a press statement to all media houses noting that the story was incorrect and should not be republished.

These points were discussed with three of the five authors of this article in a meeting in January, and the emails and articles they wrongfully cite are in their possession. Further distortions, distractions and falsehoods are evident throughout the text of the “Right of Reply”. It serves no purpose to enter into line-by-line refutation.

We call on the authors Xanthea Limberg, Gisela Kaiser, Peter Flower, Gregg Oelofse and Clive Justus to commit themselves to ethical, truthful and evidence-based governance, and address the problem at Sandvlei.

The salient facts are that the Zandvliet Waste Water Treatment Works is 10 years behind its scheduled upgrade; that the inaction of the City’s water and sanitation division in respect of Sandvlei has been the focus of critical reports by the Department of the Environment nationally, and by the equivalent ministry in the Western Cape; that the City is facing a criminal charge laid by the Sandvlei community in terms of the National Environmental Management Act. Whether or not the treatment works is responsible for the pollution in the Kuils River, requires the proper independent investigation we called for in our article.

As taxpayer-funded researchers, our team will continue to exercise academic freedom to work alongside a community in order to understand why they are suffering a complex health and environmental crisis, in a context in which their relationship with the City has broken down. We remain available to work with the City as we do so.

Ratepayers’ money, in this situation, is better spent in laboratories than on lawyers. It is cheaper to rebuild relationships with a community than go to court. It is not too late for City water officials to change course. DM

Lesley Green, Professor of Anthropology and Deputy Director: Environmental Humanities South, University of Cape Town.

Leslie Petrik, Senior Professor of Chemistry, University of the Western Cape.

Jo Barnes, Senior Lecturer Emeritus, Department of Epidemiology, University of Stellenbosch.

Nikiwe Solomon, Lecturer in Anthropology, University of Cape Town.