Below are the answers to audience question that Tim didn’t feel qualified to properly answer and has kindly gathered responses from subject matter experts.
- Basically is it safe to swim? We attended last night as we are all year round sea swimmers. I was very interested to hear of the Sewage Holding Tanks for when there is high rainfall and extra pressure on the sewerage system, and that they were very rarely full. How is it then that sewage is still going into the sea during these incidents. We regularly use the ‘Surfers Against Sewage’ app and quite often locally there are notifications that say ‘Pollution Alert Storm sewage has been discharged from a sewer overflow in this location within the past 48 hours’ saying its not safe to swim. In fact we checked last night and there were pollution alerts locally.
Many people enjoy wild swimming in rivers, lakes and the sea. There will always be some bacteria in the water, including from wildlife and agricultural run-off. So the advice from Public Health England is to avoid ingesting the water while swimming (Swim healthy – GOV.UK (www.gov.uk)). We provide information for local councils, Surfers Against Sewage and other organisations for when storm overflows operate that have the potential to affect bathing waters and inland amenity sites. This can be found on our website at www.wessexwater.co.uk/coastwatch (as you have already identified) and at Wild swimming | Wessex Water. You can also find further information about our storm overflows at Storm overflows (wessexwater.co.uk) and our improvement plans for the Bournemouth area in our Drainage and Wastewater Strategy (Bournemouth drainage and wastewater strategy | Wessex Water). I have also attached a briefing note email that explains why these overflows exist, what impact they have and what can be done to improve the situation.
- How are levels of drugs, hormones and other contaminants measured and removed from recycled water?
The UK water industry, together with the Environment Agency, have had a long running investigation (the Chemical Investigations Programme, CIP) into the various chemicals which enter our sewers from the general public or from trade effluent. Given the wide range of potential contaminants, the levels and removal vary by substance and by treatment works. We are currently working on Phase 3 of the CIP which has involved extensive collection of water quality data looking at these substances and a national evaluation of the effectiveness of WRC chemical removal. I have attached summaries of these investigations which show what we are currently doing, together with details of a project in the Bath region where we are working to sustainably reduce levels of pharmaceuticals entering our sewers. Further details of our environmental investigation programme can be found at Environmental investigations | Wessex Water. The Environment Agency have provided a useful summary of the challenges around chemicals in the water environment, available from Chemicals: challenges for the water environment – GOV.UK (www.gov.uk)
- Can COVID be detected in recycled water and how is it removed?
We’re assuming that the reference to recycled water refers to treated final effluent. We don’t have any data to say for definite, but we know COVID indicators can be detected in crude sewage samples. Along with other water companies, we have been providing samples at the Government’s request to detect traces of coronavirus, and the Government has been undertaking analysis of these samples. Further information can be found at Sewage signals early warning of coronavirus outbreaks – GOV.UK (www.gov.uk). This includes the information that “The World Health Organization is clear that the likelihood of coronavirus being transmitted via sewerage systems is extremely low or negligible”.
Our treatment processes do not guarantee 100% removal and we do not have any bespoke treatment processes specifically for Covid. We see removal of pathogens and viruses through our existing treatment processes, during the primary & secondary biological treatment stages, and tertiary treatment where installed. We are unable to confirm whether the UV (ultraviolet) treatment present at Water Recycling Centres discharging to bathing waters reduces COVID, but it is likely, given it is used to reduce other viruses and bacteria.
- What measures are in place to monitor and prevent runoff from chemicals used by Farmers?
Measurement of water quality in rivers and the sea and prevention of pollution generally from rural diffuse pollution is the responsibility of the Environment Agency and Natural England. The Environment Agency have published some very relevant information on the challenges from agricultural pollution and what can be done to improve the situation at Agriculture and rural land management: challenges for the water environment – GOV.UK (www.gov.uk).
We have been working with farmers across the Stour Catchment to tackle the problem of rising nutrient levels found in groundwater where this affects our sources of drinking water through our catchment management programme. You can find further information on our catchment management activities at Catchment management | Wessex Water. I have also attached a copy of our Stour Catchment Factsheet which provides more details on what we have been doing and our plans to increase our work with farmers in the catchment through our approach to Catchment Nutrient Balancing. We are also working closely with the Stour Catchment Initiative, which brings together a wide range of groups and organisations that share the common aim of improving the water environment of the Stour – you can find more information on the Partnership at Stour Catchment Partnership | Wessex Water.