River crossing, one side of London (9)

I believe the answer is:

brentford

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'one side of london' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'river crossing' is the wordplay.
'river' becomes 'brent' (I can't justify this - if you can you should give a lot more credence to this answer).
'crossing' becomes 'ford' (ford is a kind of crossing).
'brent'+'ford'='BRENTFORD'

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I've seen this clue in the Evening Standard.

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