Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, what assessment his Department has made of the potential impact of untreated sewage overflows on levels of (a) microplastic, (b) nano plastic and (c) macro plastic pollution in rivers.

Tackling marine litter and plastic pollution is a priority for the UK Government, which is why we are working domestically and internationally to implement measures that will prevent plastic and other litter from reaching rivers and ocean in the first place.

As part of Price Review 2024 (PR24), which runs from 2025–2030, water companies will be delivering record levels through the £22.1 billion Water Industry National Environment Programme. This includes over £11 billion to improve nearly 3000 storm overflows across England and Wales. This will help to reduce discharges of raw sewage which can contain organic pollutants, microplastics, pharmaceuticals, nutrients, and heavy metals, as well as visible litter that is flushed down toilets.

We are also taking forward investigations through the Chemical Investigations Programme, to understand how we can reduce the levels of microplastics entering the water environment through wastewater. Microplastics have been recognised as a significant standalone issue and the water industry are funding six further investigations between 2025 and 2030.

The technology for accurately measuring such small, nanometre-sized particles in complex samples such as river water is scientifically challenging. My officials are maintaining a close watch on emerging scientific evidence reporting the presence of nano plastics and the possible risks which they may pose in the water environment.