Julian Doberski’s new book, The Science of Sewage: What Happens When We Flush, explains to the lay reader what is involved in sewage treatment and the environmental impacts of sewage. In this special feature, he explains how ‘laying the blame’ for our water network’s current plight is not as clear cut as it may seem.

My book has three main sections: the history of sewage, the impact of sewage on water bodies and a technical section introducing a range of processes for converting noxious sewage to ‘clean’ treated effluent for discharge back into the environment.

Until relatively recently, these three sections would have been the end of the story. But now the story has grown – the media are awash with reports of how Nature is being destroyed and people are being made sick by sewage in lakes, rivers and coastal waters.

Although not the primary focus of the book, a comment was required on what is perceived by the public to be going ‘wrong’ with sewage, with particular reference to England and Wales. The commentary in my book is that of an ‘outsider’ – an uninvolved observer.

Until retiring I worked as an academic ecologist and have not had direct involvement with the water services industry. Nevertheless, wastewater treatment figured in my teaching of aquatic ecology and in my role as administrative leader of an eight-year EU-funded project on the teaching of wastewater treatment in east European universities.

The first obvious point to make is that technical staff working in wastewater treatment do not go to work gleefully thinking it will be a good day to pollute a river with sewage!

And for much of the time, vast quantities of sewage – out of sight and out of mind – are treated to the required level for release into a particular water body. Depending on the capabilities of the treatment plant and location, that final effluent will be ‘clean’ – that is it will meet current concentration limits for potential pollutants at that site.

As far as the public is concerned, the main problem with the water services industry is pollution by raw sewage – that is what creates the media headlines. It seems incomprehensible that raw sewage is released by water services companies – they are clearly the culprits in this story. Simple. Or is it?

Where does the ‘blame’ lie for discharges of raw sewage and other wastewater treatment ills?

Much of the media reporting suggests the answer is easy – it is clearly the fault of companies providing sewage treatment. In reality the story has several ‘actors’.

The narrative has to start with the government-driven structuring and regulation of the water industry at the time of privatisation.

Politicians chose full privatisation, that is both the management of water services and private ownership of the infrastructure. On a world scale this is an unusual arrangement.

Ofwat was created as the ‘government’ regulator of the industry– with a progressively depleted Environment Agency acting as environmental guardians of our water bodies.

In reality, regulation has proved far from stringent, according to many commentators. Ofwat, as a kind of government proxy, appears to have emphasised the need to keep water services bills low rather than promote investment by water companies and hence improved environmental performance.

This has had two consequences. A benign financial regulatory regime has done little to dissuade some water services companies from various forms of ‘financial engineering’ and accumulation of substantial debt.

At the same time the emphasis on keeping bills low has constrained Ofwat targets for investment in infrastructure. In a sense, consumers have also been complicit in this process. There is a general reluctance to pay higher bills while, at the same time, demanding improvements in the quality of treated effluent and the elimination of raw sewage spills.

These improvements will be costly and will need to provide both large scale buffering capacity for rainfall events in the sewerage system and better technology for removal of ‘invisible’ pollutants in sewage effluent returned to the environment.

These pollutants include nutrients such as nitrates and phosphates, as well as a host of artificial contaminants (xenobiotics) including pesticides, pharmaceuticals and so-called ‘forever chemicals’, whose effects in the environment are often inadequately understood.

All of this will require a quantum change in thinking about the management of water services: a collective reset by government, Ofwat, Environment Agency, water services companies and consumers. But this can only happen if governments and consumers recognise and accept the need to pay more. This would provide for extra capacity in sewerage systems, reduced sewage spills and a much-reduced environmental impact of treated effluent releases. The payback will be a major contribution to restoring many water bodies to a more ‘healthy’ state, for nature and for people.

Julian Doberski is the author of The Science of Sewage: What Happens When We Flush (£9.99 Gemini Books
www.geminibooks.com
). Julian has degrees in Zoology, Forestry and an entomology/mycology PhD. He spent 30 years in academia at Anglia Ruskin University in Cambridge (and its predecessor institutions) where he was a Principal Lecturer in Ecology.