Almost two-thirds of England’s bathing spots met “excellent” standards for water quality this year, down slightly on last year, official figures show.

Some 270 (65.4%) beaches and designated swimming lakes reached the highest level of clean water under European Union rules in 2017, compared with 287 (69.5%) in 2016, the figures from the Environment Department (Defra) revealed.

The number of bathing waters in England meeting at least the minimum standards for unpolluted water dropped slightly from 98.5% in 2016 to 98.3% this year, with seven beaches failing to make the grade at all.

They were Scarborough South Bay, North Yorkshire, Clacton (Groyne 41), Essex, Instow, Ifracombe Wildersmouth and Combe Martin in Devon, and Burnham Jetty North and Weston-super-Mare Uphill Slipway in Somerset.

But conditions have improved since 2015, when the new system of classification under tougher EU rules came in. That year, 12 beaches were classed as failing and the number rated excellent was 264 (63.5%).

For every designated bathing water in England, the Environment Agency monitors for two types of bacteria which can pollute the waters, with values potentially varying because of issues such as pollution from agricultural and urban areas and storm drain overflows.

Readings taken over the last four bathing seasons are used to determine the annual grade for the bathing spot, with this year’s results reflecting how clean the water has been from 2014 to 2017.

Environment Secretary Michael Gove said: “We want all bathing waters to enjoy the high quality which the 146 million visitors to Britain’s beaches every year expect and we will keep working with partners to drive up standards.

“Not only does our iconic coastline generate over £3.6 billion for the economy, it is a valuable part of our natural environment and we will uphold these bathing water standards as part of our plans to deliver a Green Brexit.”

Sir James Bevan, chief executive of the Environment Agency said: “Maintaining such high water quality standards at English beaches is a huge success and a credit to all those individuals and organisations working hard to keep our bathing waters clean.

“Water quality has improved significantly over the last two decades – but to protect and enhance water quality even further we will need everyone to take the small actions that will help.”