England's most dangerously polluted beaches have been revealed in an interactive map, as tourists continue to pack the coastlines for the summer holidays.
Swimmers have been warned of sewage and pollution at several beaches, partly due to storms following the heatwave.
Currently, sewers in Britain struggle with heavy rain, and sewage works can become overwhelmed.
Water firms are permitted to release rainwater and untreated sewage into rivers and the sea to stop waste backing up in streets and homes.
According to data gathered by environmental campaign group Surfers Against Sewage (SAS), there has been storm sewage discharge into the waters at beaches in Cornwall, Devon, Sussex, Essex, Lancashire, Lincolnshire, Northumberland and Cumbria.
A spokeswoman for SAS said other pollution warnings in place may not be linked to heavy rain, and those visiting the coast are advised to check its interactive map on their website before they swim.
Experts amend the map each day to reflect a real-time analysis of water quality on English breaches.
Ticks on the map mean water quality is fine for water activities, while cross marks indicate beaches which should be avoided.
Spanner and snowflake symbols mean water quality data is unavailable due to ongoing works or the beach being out of season.
At the time of writing, much of the south coast has been deemed unsafe for swimming due to sewage being released in the water.
In Cornwall there are multiple warnings, most notably on the northern parts towards Newquay.
Water quality alerts on the eastern side of the country are less common, although at some beaches in Southend, Essex, there are warnings of storm sewage being discharged on the coastline in the last 48 hours.
The Environment Agency (EA) has issued pollution alerts across the country, warning the heavy rainfall and flooding seen in recent days has affected water quality.
Heavy rainfall along with high winds at tides can all affect sea water quality, the agency said.
"Throughout the bathing season, daily pollution risk forecasts are made for a number of bathing waters where water quality may be temporarily reduced due to factors, such as heavy rainfall - as is the case today - wind or the tide," a spokesperson for the EA said.
"When the potential for a temporary reduction in water quality is forecast, we issue a pollution risk warning and advice against bathing.
"This enables bathers to make informed decisions regarding avoiding times or locations where the risk of pollution is higher than normal, and health risks from bathing may be higher than the annual classification suggests."
In October 2021, MPs voted against an amendment to a bill which would have prevented companies from dumping raw sewage.
In 2020 alone, over 400,000 incidents of sewage being released by water companies were in Britain, wreaking havoc on water quality.
Environmental campaigners have called for better infrastructure such as storage tanks.
They say raw sewage can be dangerous to local wildlife and anyone who enters the sea.
Last week, the government's water minister threatened to fine companies after it was revealed that billions of gallons of water is being lost in leaks every day, in addition to sewage releases.
Steve Double insisted water firms needed to do more to stop water being wasted, especially in the face of hotter and drier summers.
"Water companies must continue to invest more, including to prevent leakage and work faster to fix leaks," he told The Mail on Sunday.
"We are losing somewhere between 15% to 20% annually through leakage, which is not acceptable.
"Progress has been made but my message to water companies is they need to prioritise customers, not shareholder returns. If we don't see the progress we expect, we won't hesitate to take further action.
"The public and government rightly expect more from our water companies."