Thousands of people are expected to join a large march in London this weekend in protest against the pollution of Britain's rivers, lakes and seas.

Chris Packham, Bear Grylls, Carol Vorderman, Johnny Flynn and writer Robert Macfarlane are among celebrities who have thrown their weight behind the March for Clean Water, which will be held in central London on Sunday, 3 November.

The "peaceful, family-friendly and inclusive demonstration" will gather at Albert Embankment at 11am.

The march will then begin at 11.45am, taking protesters to Parliament Square where a rally will take place between 1.30pm and 3pm.

More than 130 organisations have pledged support for the one-off march including the National Trust, RSPB, Wildlife Trusts, Women's Institute, Extinction Rebellion, WWF, Greenpeace, Angling Trust, Rivers Trust, and British Rowing.

It is being organised by environmental charity River Action, which describes itself as being "on a mission to rescue Britain's rivers" with campaigns aimed at tackling sewage and agricultural pollution.

Organisers say the march "calls on Prime Minister Sir Keir Starmer to end the pollution of Britain's rivers, lakes, and seas, or face the consequences of broken promises".

"The March for Clean Water is a call to action for millions of people who care about the future of Britain's waters," they said.

"Join us on Sunday 3 November, wear blue, flood the streets and make your voice heard."

Participants are also invited to bring with them samples of water from their rivers, lakes and beaches – which will all be combined into a single vessel before being symbolically returned to the River Thames at the end of the march on the outgoing tide.

Broadcaster and campaigner Carol Vorderman, who will be joining the demonstration, says it will be the first time she's attended a protest.

She said: "I'm 63 and have never been on a protest before."

 "This is my first ever march. That is how much the disgraceful privatised abuse of our water system matters to me. I can't wait to add my voice to thousands on the day."

The march will also feature Extinction Rebellion drummers, and a seven-metre-long sculpture of a whale made from plastic collected from rivers and oceans

It comes as years of underinvestment, a growing population and extreme weather caused by climate change have led to intense pressure on England's ageing water system, causing sewage pollution.

Public anger has swelled over the state of the country's rivers, lakes and coastal waters and at a lack of investment in water infrastructure, despite rising bills, and high executive pay and bonuses at privatised water firms.

Figures showed sewage flowed into London's rivers for almost 10,000 hours last year.

Waste was dumped into the capital's waterways for more than 9,773 hours — up significantly from the nearly 7,000 hours reported in 2022.

A large contingent from Ham, Teddington, North Kingston, Twickenham, and Richmond are expected to join the March.

Berni O'Dea from Kingston said: "As a supporter of Save Our Lands and River (SOLAR), I'm joining Sunday's march to oppose Thames Water's proposal for the River Thames in Teddington. It's ridiculous short-term thinking with permanent long-term damage.

"What's more, the regulatory oversight needs to be improved so that environment protection is at the core of how we improve the water system in this country."

Ian McNuff, local resident from Teddington said: "Thames Water are proposing a bad value, treated sewage disposal scheme. If approved, their Teddington Direct River Abstraction proposal will dump known pollutants into the Thames. There are much better, cleaner alternatives."

A Thames Water spokesperson said: "The Government's approval of our Water Resource Management Plan shows confidence in the solutions we are proposing to ensure London is drought-ready and drinking water supplies are not at risk.

"Our water abstraction and recycling proposals are a vital part of the solution and a commitment to maintaining river health at Teddington is central to our proposals. To be absolutely clear, the recycled water produced through the tertiary treatment process will comply with environmental standards and will not deteriorate the water quality of the River Thames."