Untreated sewage discharges and unpermitted outfalls have caused dangerously high levels of bacteria to be found at multiple sites across a nine-mile stretch of the River Roding, London’s third longest river, a new study by environmental charity Thames21 and The River Roding Trust has found.
Citizen scientists who worked with these environmental organisations between 15th May and 30th September 2024 on a water quality monitoring programme found that samples they took at seven sites across the River Roding failed to meet sufficient bathing water regulation standards for safe swimming for both E. coli and Intestinal Enterococci.
E. coli can cause risks to human health such as diarrhoea, stomach cramps and fever.
The study also highlighted that multiple combined sewer overflows (CSOs) are negatively impacting this stretch of river. Nine CSOs discharged untreated sewage for a total of 316hrs, causing clear spikes in bacteria levels at many sample points during the monitoring programme, at times in periods of very little rainfall.
The River Roding has its source in rural Essex and flows through East London before joining the River Thames at Barking Creek and the sampling sites citizen scientists analysed were between Chigwell and Barking.
Results were analysed against the Bathing Water Regulations (2013) standard for FIO (‘Faecal Indicator Organisms’) levels in inland waters, which the Environmental Agency uses to assess and classify designated bathing water quality[1]. Through this method, the project aimed to answer the question: is the River Roding fit to swim and paddle in?
The results also showed that an unpermitted outfall on the Alders Brook (a tributary of the Roding) appears to be severely impacting water quality in Ilford, which saw the worst results of all sampling points.
Sites upstream saw better water quality, with the lowest bacteria levels found in Woodford. At this site, CSO discharge events negatively impacted three sampling dates. If these were removed, this sample point would have received an overall ‘good’ bathing water status. This demonstrates that with the right investigations and improvements, a healthier River Roding is within reach.
Chris Coode, Thames21’s CEO, said: “The Environment Agency, Ofwat and Thames Water must take immediate actions to address the critical issues highlighted by this citizen science monitoring programme. The harmful levels of bacteria detected demonstrate significant failures within the wastewater network, where CSOs and unpermitted outfalls are allowed to discharge raw sewage, posing serious risks to human health and nature.”
Paul Powlesland, founder of the River Roding Trust, said: “It is heartening that, thanks to the efforts of local volunteers, we now have a picture of water quality on the Roding for the very first time. We now need the Environment Agency to do its job as guardian of the river and act on this report by stopping all illegal sewage spills on the Roding.”
Councillor Jo Blackman, cabinet member for environment and sustainability at Redbridge council, said: “The publication of these water quality results provides a stark reminder of the need for action to tackle the pollution of the Roding. We have already written to Thames Water and the Environment Agency to demand action to address the causes of this pollution which poses a risk to people and wildlife, and will be using this data to make the case for further action.”
Climate change will bring hotter summers and wetter weather in general, and as such there is a clear need for safe access to healthy waterways, especially in regions of London that are densely populated but have little access to recreational blue space.
Residents local to the Roding have expressed the wish to be able to swim in the river, but also major concerns over its water quality. This report highlights the need for improved governance and regulation to futureproof our waterway infrastructure and river health so that it is fit for the demands of the 21st century. It contributes much needed data to the understanding of river health on the Roding, which on this stretch is not fit to swim in, with pollution levels causing risk to human health and wildlife.
