The Allyn River is a NSW river that runs into the Paterson, and the reason to bring a fly rod is carp: they are the one fly target on its recorded fish list, and a carp that takes a fly in clear, slow water is a fair test of anyone's casting.
Think of it as one river with one bottom end, where it joins the Paterson River. In our experience the simplest plan is to pick one access point, walk the water near it and judge the river from there, rather than trying to cover it all in a day. The hydrology chart shows how flow usually moves through the year, and the flow chart shows the river's typical range and where high water starts; for planning, those matter more than any map.
The trip worth making is a warm-weather carp session. Pick one of the access points on the access card and walk the banks looking for fish before you cast: tailing carp in the shallows, cruisers along a slow edge, mud clouds where they have been feeding. Clear water and a bright sky make that far easier, so time the walk for the middle of a calm day and wear polarised glasses. A carp you have seen before it sees you is most of the job done. No water-specific rule was found for the Allyn, which in practice means the season, limits and licence you fish under come straight from the current NSW guide, so read it first.
Eels are the other fish you are likely to meet. Longfin eels have been recorded in the river, but they are not a fly target. If one takes a nymph meant for a carp, in our experience it is kindest to unhook it quickly in the water.
Pack a 6 or 7 weight, a few small weighted nymphs and a small dark streamer, check the flow chart and the live conditions card, and read the NSW fishing guide before you leave home.
Water and habitat
The Allyn gathers its water and delivers it to the Paterson River. The flow chart shows its usual range and where high water begins, and the hydrology chart beside it shows how flow and water temperature move through the year, which in our experience is a fair guide to when fish will be active.
In our experience, carp in a river like this sit wherever the current eases: the slow margins of pools, the flats below a bend, soft water behind a snag. They feed with their heads down on the bottom, so the water you want to look into is shallow, slow and clear enough to see a tail or a puff of mud.
Fish and forage
Atlas of Living Australia records for the Allyn list a short set of fish. European carp are the fly target. Longfin eels are recorded too, but they are not a fish you target with a fly. Cox's gudgeon and Australian smelt are the small fish.
For the fly box, that means two kinds of food. In our experience carp feed mostly on the bottom, on small insects, snails and whatever they root out of the mud, so small weighted nymphs in dull olive, tan and black are the core. The smelt give you a reason to carry a small, slim streamer as well. The survey chart shows how lightly the river has been sampled, so treat the list as a starting point rather than every fish that lives there.
When to fish it
In our experience, carp fishing on a NSW river is a warm-weather game. From late spring through summer and into early autumn, carp feed more openly and move into shallow water where you can see them. Mornings and still, bright days make spotting easier. In the cold months carp slow down and hold deeper, and sight-fishing gets hard. Whatever the month, check the flow chart and the live conditions card before you leave: after heavy rain, give the river time to drop and clear, because you cannot fish to a carp you cannot see.
How to fish it
Walk slowly, keep low and look before you cast. A 6 or 7 weight rod, a floating line and a leader of about 9 feet down to a 3X or 4X tippet will handle a carp without spooking it.
When you find a feeding fish, put a small weighted nymph, size 10 to 14, a little ahead of it and let it sink to the bottom in its path. Carp pick food up gently, so watch the fish rather than the line: if it tips down or stops over the fly, lift. Long casts that land on a fish's head scatter it, and a short, soft cast from behind and to one side works better. In slower, deeper pools where you cannot see into the water, a small dark Woolly Bugger crawled slowly along the bottom is a reasonable way to search.
Access and safety
The access card names the access points. Treat them as locations, not a statement of permission, and respect any fence or sign you meet on the ground.
As on any river, tell someone where you are going and when you expect back, carry water and a small first-aid kit, and watch your footing on muddy or undercut banks. Keep an eye on the weather: a river can rise quickly after rain upstream, so check the live conditions card and never wade a crossing you are unsure of.
Regulations
No water-specific rule was found for the Allyn River. Before you fish, read the current NSW Department of Primary Industries and Regional Development recreational fishing guide, including what it says about licences, bag and size limits, closed seasons and closed waters, and take the rules from it.
