Some beaches in Cornwall might lose their status as designated bathing areas under new European rules on water quality.
All beaches must achieve a certain standard of cleanliness by 2015.
The Environment Agency has said some beaches in Cornwall, including East Looe, Par and Rock, risk failing.
Cornwall Council said it was working with the agency, South West Water, Surfers Against Sewage and the Health Protection Agency to address the issue.
Geoff Penhaligon, Looe's harbour master, told BBC News poor water quality in Looe was only a problem after heavy rainfall.
In Devon, some local councils are considering changing the designation of beaches that fail so they are not labelled as bathing areas.
But Cornwall Council said it had no plans to apply for de-designation at any of the seven beaches under scrutiny from the Environment Agency.
The European Commission introduced a revised bathing water directive in 2006. The key changes included a requirement to provide information about bathing waters to the public on signs, beaches and online.
It set out four new standards of water quality - excellent, good, sufficient and poor - and all bathing waters will be expected to achieve at least the "sufficient" classification by 2015.