Friday 10 August 2012 7.28pm
Planning permission wouldn't be required for repairs to be carried out.
I don't think there is a public right of way across the bridge or neighbouring wharves (though, as you say, it is part of the Thames Path national trail - but that's not the same thing).
Closure of a public highway for works would require formal public notices etc, but this isn't a highway either.
If local residents have been notified by letter a few weeks in advance, that would seem reasonable enough.