Boris Johnson has written to the Environment Agency (EA), asking it to review operation of the Thames Barrier.
The Barrier, built across the river at Woolwich to protect central London from tidal surges, closed 50 times this winter. The EA's own guidance recommends not closing the Barrier more than 50 times a year as a safety measure — so many repeated closures don't leave enough time for maintenance.
Of course, this winter was exceptional in terms of rain and storms, but the Mayor has asked the EA to conduct a full review to ensure London's primary flood protection is still up to the job. The Agency believes the Thames Barrier will be fine until 2050, but warns that as the sea level rises in line with climate change, the Barrier will need to close more often than it has been. If climate change also makes the kind of weather we had this winter a more regular occurrence, the Barrier could be closing 50 or so times a year as a matter of course, and that increases the risk of failure.
In December the Environment Agency released an image showing what could happen if the Thames Barrier failed:
In exchanges during February's Mayor's Question Time, Boris Johnson told Jenny Jones:
"in view of the many times that [the Thames Barrier] has been in operation and continues to be in operation over the last few weeks and months, it is only prudent to have a full review of its operations."
Thames Barrier photo by Dave Banbury from the Londonist Flickr pool