A final Blue Flag is likely to flutter over Bognor Regis seafront next summer.
The last of the prestigious awards for the eastern beach should be awarded for 2012.
But the arrival of strict new water-quality results imposed throughout Europe means future awards are unrealistic.
Councillors were given the bad news on Monday at Arun District Council’s safer Arun and environment working group.
They agreed to lessen the impact on the town’s tourism image with a commitment to apply for the Quality Coast Award for 2012-14.
This requires a lower standard of water cleanliness than the Blue Flag.
They also agreed pressure should continue to be applied to Southern Water to install ultra-violet water treatment at its Ford waste water treatment works as soon as possible.
Phil Graham, the council’s marketing, events and filming officer, told the working group: “For 2012, the water-quality results obtained in the 2011 summer season for both Bognor and Littlehampton permit the council to apply for the 2012 awards.
“However, this will be the last season when we will be able to realistically meet the more stringent water-quality requirements.
“In 2012, all Blue Flag applications covering the 2013 season will have to comply with the new European bathing water directive and the water quality will be measured over a three-year average.”
Projected results showed Bognor would reach only ‘good’ water quality.
“A coastal destination can only apply for a Blue Flag award if the water quality is of a higher guideline – excellent – standard,” he said.
Bognor’s town mayor, Cllr Jim Brooks, said: “The rules are there to ensure the highest standards and it does seem unfair they are being changed from one year to the next.
“The town council has already met Southern Water several times about improving the seawater quality and we will continue to talk to them and the Environment Agency to achieve that.”
The Blue Flag and the Quality Coast Award also rely on a series of onshore requirements which Arun has always met.
These include cleanliness, toilets and safety and security. Bognor has had mixed successes with the Blue Flag.