Not a lot of land based in karratha unfortunately.. have a walk down withnell bay to the right of the car park, or go for a drive to cleaverville (between karratha and roebourne) 

Cleavers is the better bet :)

Crossing/Bridge/causeway. On a just high to outgoing tide fish the oceanside with either surface lures or Soft plastics. Dont let the lure sink to far or it is buy another, as it is very snaggy there. Should be able to get some queenies, trevors, jacks and even if you are very very lucky a barra (thought I jagged one there, but one closer inspection was a fool's barra sand bass)

Tide is critical realy. Otherwise the Kcity side off the upstream edge of the causeway in close to the rocks you can get all sorts of little sportsfish, but usually nothing to brag about. And it is bait here as lures are not good IMO here.

As mentioned Cleaverville mouth is OK, and possibly score a black jew. Again tide and patience. Have a set line out with bait (mullet esp fresh best, or live) and then ping away with lures. Run out tide important.

Back Beach when water very hit/miss, but you can get lucky.

Dampier side again very tide dependent. Can try the little Marina just b4 the Intercourse Island crossing for jacks, but you need to get very close to the pylons and have a deep diver you can drag down fast, or a plastic to get to the bottom. Also some Pikeys and other odd's and sods in there. Never had much luck on the outside apart from the odd squid but others fish it (just never seen a good catch).

Incoming you can always sit at Hearsons and get some big YFW, shovels etc. Just dont do what we did when we first got there and stay long. The locals must have pissed themselves laughing because we were fishing in 3inches of water.

Otherwise if access to a good 4x4 head to the Jump up and over and beyong there is a heap of beatiful beaches. BUT Google how to as a few sumps, side steps etc has been taken out here by inexperienced drivers.

 thanks heaps guys!!!