A sluice protecting hundreds of homes and thousands of acres from flooding was officially re-opened today after a �1.8m refurbishment.

North West Norfolk MP Henry Bellingham unveiled a plaque on the Relief Channel Tail Sluice, on the outskirts of King's Lynn – next to the plaque unveiled by the Duke of Edinburgh, when the structure was completed in 1959.

Mr Bellingham said: 'It's a very important part of our sea defences, river defences and protecting our community.'

Dr Geoff Brighty, area manager for the Environment Agency, said one of its key priorities was protecting people and property from flooding.

'The Tail Sluice is a hugely-important asset, so it's worth maintaining and investing in for many years to come,' he said.

Ryan Ely, the EA's project manager, said the work was phased over three summers to ensure only two of the gates would be closed for repairs at a time.

New lifting chains have been fitted to the 11-tonne gates, which have also been repainted and given new seals.

The Relief Channel, stretching from Denver to Sluice to Saddlebow, was built after the 1947 floods.

The 12-mile waterway acts as a reservoir, storing excess water from the River Ouse between tides, to prevent flooding further inland.

As the tide falls in the River Ouse, the gates can be opened to allow water from the channel out to sea.

'This is the last line of sluices along a flood protection scheme that stretches all the way from Barton Mills in Suffolk,' said Mr Ely.