British water sports bodies have banded together to demand the government tackles the sewage crisis, which they say is a “death knell” for many activities in the UK.

The volume of untreated sewage dumped into rivers and seas reached a new record last year, further fuelling public anger over pollution and privatised water companies, which many argue prioritise profit over investing in infrastructure.

The Clean Water Sports Alliance, which represents anglers, rowers, triathletes, sailors, paddleboarders, canoeists and swimmers, said training sessions, activities and events are being cancelled or postponed across the country due to unsafe water quality.

The dirty water is making users of British waters ill, says the group representing seven national governing bodies of the water-based sports.

Read more: ‘Shocking’ incidents of sewage in gardens – with disease outbreaks ‘very possible’

The Angling Trust, British Rowing, British Triathlon, GB Outrigger, Paddle UK, Royal Yachting Association and Swim England together represent 450,000 people involved in the outdoor activities.

“We are advocating for the restoration of our blue spaces for the enjoyment of all,” the Clean Water Sports Alliance said in a statement on Tuesday.

Last month, rowers in the historic Boat Race between Oxford and Cambridge, who for nearly two hundred years have celebrated by jumping into the River Thames, were warned not to expose themselves to water because of high levels of E.coli bacteria from sewage spills.

Cameron Taylor, chief executive of GB Outrigger – which represents people who enjoy a form of canoeing called outrigging – said: “Polluted water is a death knell for British sport.

“Clean water needs to move from being considered a ‘nice to have’ to a literal ‘we can’t live without’. Without clean water, we do not exist.”

Many coastal waters, rivers and lakes across Britain are being contaminated by pollution and sewage spills due to creaking water infrastructure, intensive farming, a growing population and climate change.

Thames Water, which has a large debt that could force it to be nationalised, has become a focal point for campaigners, outraged by its poor environmental record and financial woes.

The alliance is calling on the government to sufficiently fund the regulators so they can hold polluters to account, and for compulsory monitoring of all sewage outlets, with real-time data on water quality.

Government and water industry accept pollution is ‘unacceptable’

A government spokesperson responded by saying: “Sewage pollution in our waters is unacceptable, which is why we have taken action to ban water bosses’ bonuses when criminal breaches have occurred, quadrupled company inspections next year, provided more funding to our water regulators and fast-tracked investment to cut spills.

“100% of overflows are now being monitored and if water companies are found to breach their permits, action will be taken – up to and including criminal prosecution.

“We also need to be tackling every source of pollution – not just from storm overflows, but also agriculture, plastics, road run-off and chemicals.”

A Water UK spokesperson said: “We agree everyone should be able to enjoy our rivers and seas. The quality of our bathing waters has transformed with seven times as many beaches classed as ‘excellent’ since the 1990s.

“All storm overflows in England are now monitored and water companies are publishing interactive maps so anyone can see exactly what’s happening, as it’s happening.

“However, sewage spill levels remain unacceptable, so water companies in England have proposed £10bn to reduce spills by nearly 40% by 2030.”