This is the kind of structure that could be on the way to Somerset to save Bridgwater and the Levels from tidal flooding.
Picking up the flood action plan last week, environment secretary Owen Paterson said there was "some merit" in building a tidal barrier across the River Parrett because he had seen one in operation in Hull.
Like the Somerset Levels, the Humber estuary is on low-lying land and complicated drainage schemes have safeguarded the area for hundreds of years.
In 1980, the Environment Agency constructed a tidal barrier at the mouth of the river and a huge steel gate weighing 202 tonnes is lowered into the waterway whenever high tides threaten to engulf the city and low-lying areas beyond.
The gate effectively seals the river from the tidal surges rushing up from the Humber – and recently had a £10 million upgrade to keep it operational for a further 30 years.
It is currently used around a dozen times a year but there are concerns that even this will not be enough to save the city from rising sea levels in future. In December 2013 there was a major emergency when the barrier came within less than eight inches of being breached by the highest tides for decades.
Although some homes and businesses in the city centre were flooded, the barrier, together with the flood defences along the Humber, are estimated to have protected about 100,000 homes and businesses from a £230 million disaster.
There are long-standing plans to build another barrage where the River Hull joins the Humber estuary, to keep water levels constant through the city, but in 2007 this was estimated to cost £195 million and many believe it will be too big a drain on the public purse.
The massive barrier gate can be deployed within 30 minutes and there have been 33 severe tidal surges since the barrier was constructed
Speaking on BBC Radio 4's World At One about proposals for a barrage on the Parrett downstream of Bridgwater, Mr Paterson said: "It would be a significant investment of £27 million to £30 million.
"I asked the Environment Agency yesterday to rapidly bring up a proper proposal for a physical project to put in a sluice or a barrage to keep out the high tides and also to keep out the silt which tends to come in from the sea and then drop. I think, having seen a similar operation on the Humber in Hull, I think there's real merit in this."