Thames Barrier breach likelihood

[NoelWatson]

Was reading the Evening Standard last night and it was discussing how London would cope with a natural disaster. Saw this in the comments

http://www.thisislondon.co.uk/standard/article-239...

"It is reported that water has never risen more than seven feet below its top, which is well within even the grimmest global warming scenarios"

but from the comments

"In November 2007, the Thames Barrier came within less than half a metre of being breached"

Any idea who is correct?