PH if it is the estuary that I am thinking of, then you must take some smallish topwater lures. That river has been closed to the sea for some time, but opened up a few weeks ago after some heavy rains. A lot of the water has run out, creating some interesting options. It fishes well from 4pm to around 9pm, with most action around just after sunset. A lot of the river is shallow at the moment and you can wade to within casting range of rock structure that you want to fish around. A fishing ski would be a good option to getting around, I think the whole fishable area of this river is about 4km max. You want to concentrate your fishing around the rocks, working surface lures very close to them. Lures I would recommend would be Rapala X-Rap Walk 9cm, Heddon Zara Puppy and Rapala Shallow shad rap 7cm. The shad rap should be worked very slowly with small twitches, allowing it to float to the surface between each short twitch (you only want it to dive about 10-15cm). Work these lures close in to each and every rock and crevice around dawn/dusk and you will have sport. Casting accuracy is key, you must get your lure to land within centimetres of the rocks.
The lagoon part near the mouth area is mostly sandy, with rocks in the mouth itself. I would focus most of my efforts on the rocks that you can see exposed about 600m upriver from the mouth. There are some rocks in the middle of the river and then a whole lot along the south bank at the same spot, (just below the bay/creek inlet) That is where I had most action on my last visit a few weeks back. I am sure you will have some fun there. PM me if you want any more details