“Public waterways are a great resource enjoyed by many children and adults and can have a significant positive impact on our health. Whilst there will always be challenges with the efficient management of sewers and sewage treatment works, minimising the entry of human organisms that can cause harmful infection should be a major priority. This report provides clear options for how this can realistically be achieved.”  Professor Sir Chris Whitty, Chief Medical Officer of Health

[Remember SWW claims that Jo Bateman has no inherent right to swim in the sea. – Owl]

National Engineering Policy Centre raeng.org.u

Key findings of the report

This report examines the interventions available to reduce the public health risks associated with using open waters for recreation that may be polluted with faecal organisms from human waste in sewage.

It outlines 15 recommendations for water service providers, UK government, devolved administrations and public bodies to reduce public health risks posed by polluted water. The report’s findings are based on risk-based assessments and consultations with more than 100 engineers, wastewater experts, the water industry, campaign organisations and policymakers.

It focuses on the role of wastewater infrastructure in introducing primarily human faecal organisms into open water through storm overflows and treated wastewater. However, it does not look at agricultural runoff from livestock, wild animals, or septic tanks.

What engineering interventions could we implement to tackle wastewater pollution?

There are a range of interventions that could be deployed across the wastewater system to reduce the public health risks for recreational water users (such as swimmers, anglers and surfers). The report looks at interventions in four broad categories:

• Water management: These interventions seek to reduce the volume of water entering combined sewers to reduce the number of overflows and reduce exposure to polluted water.
• Wastewater treatment: Improving the quality of pathogen removal to reduce the hazard of treated effluent or overflows.
• Monitoring and communicating risk to the public: Reducing exposure by providing better information to the public.
• Maintenance and operations: Improving performance of infrastructure to reduce the number of overflows and improve the quality of treatment.

Recommendations to reduce public health risk

The report makes 15 recommendations which target situations where the risk to public health is highest whilst also balancing cost and other policy priorities. The recommendations can be split between three groups; immediate actions, long-term transformational opportunities, and enabling actions. 

• Asset maintenance.
• Environmental monitoring. 
• Bathing water review.
• Overflow management.
• Runoff reduction.
• Collaborative modelling.
• Public engagement.
• Disinfection assessment.

Explore the recommendations in full

• Visionary strategy.
• Sustainable drainage.
• Water efficiency strategy. 
• Innovative treatment funding.

• Research investment.
• Skill development.
• Wastewater champion.

What is our current wastewater system in the UK?

Any interventions made to the wastewater system to reduce public health risks must consider the context of existing infrastructure and working practices. The recommendations made in the report consider the design and workings of the sewerage system, the wastewater treatment process, the effect they have on faecal organisms, and the governance of the system.

Sewers and drainage

Our sewerage system’s primary role is to remove human excreta and other domestic and industrial wastewaters from properties to protect public health. Sewers collect and convey wastewater to wastewater treatment works where pollutants are removed to protect water quality before the water is returned to a natural body of water.

Sewage treatment

There are around 9,000 wastewater treatment works in the UK. The treatment processes that are deployed depend on the size of the works as well as factors such as the contents of the wastewater, the sensitivities of the catchment that treated effluent is discharged into, and how that catchment is used. Broadly the process is the same across most sewage treatment plants with a primary step to remove large solids and a secondary step involving biological treatment to remove more organic matter. 

System governance

Policy oversight for management of the water and sewerage system is devolved across UK administrations. Government sets the policy framework and then national legislation for water and sewerage services is set by the devolved administrations. Dedicated regulators then set standards, targets, and grant permits for key areas of operation and governance.

What happens next?

It is important that collective action by industry, government, and public bodies is taken to improve the UK wastewater system. This report calls for an evidence-led, risk-based approach to reducing public health risks of both overflows and continuous effluent discharges. 

Work is already being done to improve the wastewater system and generally reduce overflows, including funding for sustainable drainage, increasing storage, and rolling out UV disinfection. However, this activity needs to be guided by an ambitious vision of our future wastewater system. 

This vision should underpin regulatory instruments, technical standards, and policy targets across the UK, so that together governments, regulators, and water service providers can effectively mitigate the public health risks and provide safe open waters for everyone to use.

Explore the full report

Foreword from:

Professor Sir Chris Whitty FRS FMedSci Chief Medical Officer for England

Managing the threat of cholera epidemics, typhoid and many other water-borne diarrhoeal diseases was central to the birth of scientific public health in the UK, and has remained central to it since. The remarkable feats of engineering which separated human faeces from water we come into contact with, and in particular from contaminating drinking water, broke the chain of transmission of the major faecal-oral diseases which were previously a major cause of mortality in children and adults. It was one of the greatest public health triumphs of the last 200 years, responsible for saving millions of lives globally. The principal reason for the existence of the sewerage system is to protect public health.

Minimising ingestion of human faecal pathogens bacteria, viruses and parasites- remains a public health priority. Whilst we continue to have safe drinking water, ensuring both fresh and sea water people regularly come into contact with through leisure or other activities has a minimum number of viable human faecal organisms is one of the many contributions engineering makes to public health. 

There are two principal routes of human faecaloral organisms into public waterways in the UK, both of which have potential engineering solutions. The first is raw sewage entering rivers or the sea Foreword via storm overflows which has received extensive attention over recent months. The second is via continuous effluent discharge from routine sewage works operations. Whilst sewage effluent has undergone treatment processes which significantly reduce the risk, it still can contain viable human bacteria and viruses which have the potential to cause serious disease if ingested. 

I therefore welcome this report from the National Engineering Policy Centre, which demonstrates the many possible solutions available for use across sewage systems and treatment works of varying sizes and settings. It clearly sets out that to reduce the public health risk significantly, a combination of practical solutions can be implemented and tailored to each context. 

Public waterways are a great resource enjoyed by many children and adults and can have a significant positive impact on our health. Whilst there will always be challenges with the efficient management of sewers and sewage treatment works, minimising the entry of human organisms that can cause harmful infection should be a major priority. This report provides clear options for how this can realistically be achieved.