from where you were by B & Q etc, go towards town and around the one way system, turn left at the clocktower and at the traffic lights by the BP station take the second turning left and follow the road for about a mile which brings you to denton wharf, keep going and at the end of the road there's a pub car park
the owner has just changed hands so better check if its OK to park in there, if not then park on the ramp
go round the front of the pub and look over the wall, theres a small shingle beach onto mud but if you walk along downriver you get rocks close in with mud beyond, its well worth just visiting at low water so you can check the area out as the tide can go out for quite a way, most places its 3 hours each side of high water but further along towards shorne fort you can fish the whole tide, but thats a bit of a hike