Another possible alternative is Bargehouse Causeway at Woolwich ,but again a 4X4 essential , and personally . I would not try anything over 5M other than at High Tide ( Slack Water ). At low tide , slip is very shallow and ends vertically ! There is Gallions Point Marina a few hundred metres downstream , so if there are at least two of you it's a possibility. ( also suggest that you dont leave car and trailer there - Access to Marina just round corner ).
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