The Hawkesbury-Nepean rises in the Blue Mountains foothills and winds east to meet the sea at Broken Bay. National parks adjoin the Hawkesbury region.

The upper reaches are the bass and perch water, with many kilometres of creeks and banks. In our experience the fish hold on fallen timber, rock bars and the mouths of side creeks, and the shaded side of a snag is a good bet through the middle of the day.

Below the freshwater the Hawkesbury is a particularly deep system. That depth is what shapes the tidal fishing: in our experience the fish hold in holes, along steep edges and around structure, and they are seldom in reach of a floating line. Where a sand flat drops into deeper water, the drop-off is a good bet for flathead.

Water movement is the other driver. The NSW fishing guide’s advice is that mulloway become most active and feed close to a tide change, when the water movement slows down. That is why its plan for mulloway is built around the change at several spots in one day.

The two fish that make the upper river are Australian bass and estuary perch. They share water and habits, and the same fly box covers both: surface poppers and gurglers for low light, small baitfish and shrimp patterns for the rest of the day, and a weighted pattern for fishing deep along a snag.

The river also holds flathead, tarwhine, whiting, mullet, garfish, leatherjacket, flounder, drummer, silver trevally and snapper, and the mulloway the river is known for. Pike eels, red rock cod and catfish turn up too.

The small fish recorded in the system are gudgeons, blue-eyes and gambusia. In our experience that points to small, drab baitfish a few centimetres long as bass and perch food, and a size 4 to 8 Clouser-style fly in olive, brown or grey covers that. In the tidal water, a good bet is that the fish are on prawns and small baitfish, so scale the same idea up to a size 2 to 2/0 baitfish fly for flathead and a large, heavy fly with plenty of movement for mulloway.

In our experience bass and estuary perch fish best through the warm months, from spring to autumn, when they take a surface fly at dawn and dusk in the upper river and its creeks. Summer evenings after a hot day are a good bet, and the cold months are usually quieter.

In our experience flathead follow warmth too and are most reliable from late spring to autumn on the drop-offs.

Mulloway are a tide fish more than a season fish. The NSW fishing guide’s advice is to pick several spots along the river and fish each near its tide change, when the water slows and the fish feed. Because the change arrives later the further you are from the mouth, you can move upstream through a day and meet the slack water again at each stop.

For bass and perch, rig a six or seven weight with a floating line and a short, stout leader. Fish from a kayak or small boat and cast tight to structure: a surface fly worked with pauses at first and last light, then a small weighted baitfish or shrimp pattern on an intermediate line once the sun is up. Accuracy beats distance. A fly that lands a metre off the snag is a fly the fish did not see.

For the tidal river, step up to an eight or nine weight with a fast-sinking line and depth control as the whole game. The NSW fishing guide suggests soft-plastic anglers use jig heads of 7 to 21 grams on 2/0 or 5/0 heavier gauge hooks, because the river is deep and a mulloway may turn up as well as the flathead; take that as your cue. Count the line down, let the fly touch bottom, and retrieve with long slow strips and pauses along a drop-off or through a hole.

For mulloway, plan the session around slack water at each spot. Fish a large, heavy fly with a big profile and plenty of movement, deep and slow, along holes, pylons and rock walls. Expect long stretches of nothing. A fish around the metre mark is a real possibility here, so tie the fly on a strong hook and use a leader you can lean on.

Handle every fish for release with wet hands, keep mulloway and big flathead in the water for the photo, and as with any estuary fish, mind spines and teeth when you unhook.

The access card shows the public boat ramps and the angler access sites along the river. Use it to choose where to start for the part of the river you plan to fish.

As on any big tidal river, wear a life jacket in a kayak, carry a means of calling for help, and keep clear of larger craft. Check the marine forecast before you head down toward Broken Bay. If you wade a flat on the ebb, know your way back before the tide turns.

The Hawkesbury region is also a popular tourist destination for cruising, sailing and kayaking, so expect company and fish early.

No rule specific to the Hawkesbury River was found. The river runs from fresh water into tidal water, so two sets of NSW rules can apply along its length: the freshwater rules in the upper river and the saltwater rules in the tidal reaches. Check each species you are after, bass, estuary perch, mulloway or flathead, for a bag limit, a size limit and any seasonal protection.

Before you fish, read the current NSW fishing rules and regulations, check the bag and size limits for the species you are after, and confirm the fishing fee and exemptions. Look for any marine park, aquatic reserve or local closure along the reach you plan to fish, and treat the signs at the ramp as the current word.