Causeway Lake

Causeway Lake sits halfway along the Scenic Highway between Yeppoon and Emu Park, where a bridge and rock wall built across the mouth of Mulambin Creek in the late 1930s turned the creek into a shallow tidal lake. The ocean only pours in over the rock bar on the bigger tides, and that "run-through" is the whole show: barramundi, mangrove jack, trevally and queenfish push in with the water, while bream, grunter, estuary cod, flathead and whiting live in the lake full time. With shade, barbecues, play equipment and a fish and chip shop next to the bridge, it is the coast's classic family fishing stop. Few road projects from the 1930s still draw a crowd every time the tide tables print a big number.

Time your visit for a big high tide and fish the run-through, when the sea spills over the rock bar and pushes through under the bridge. Cast soft plastics, small vibes and shallow hardbodies into the current on the seaward side for trevally, queenfish, jacks and barra; a live prawn or poddy mullet drifted with the flow does the same job with less effort. In the lake itself, fish lightly weighted prawns and yabbies from the open bank, well back from the edge, for bream, grunter and whiting, and work a soft plastic slowly over the sand for flathead. When the rock bar gets crowded, fish the open bank by the bridge from well back, not the mangrove edges.

The run-through brings the glamour fish — barramundi, mangrove jack, giant trevally and queenfish — while yellowfin bream, grunter, estuary cod, flathead and whiting are the everyday catch inside the lake. Barramundi are a 58–120 cm slot with a possession limit of 5 and are closed from 1 November to 31 January. Mangrove jack are 35 cm minimum, limit 5. Estuary cod are a 38–120 cm slot in a combined limit of 5 with other cods and groupers. Grunter (barred javelin) are 40 cm, limit 10; yellowfin bream 25 cm and sand whiting 23 cm, each in a combined limit of 30; dusky flathead a 40–75 cm slot, limit 5.

The lake only refills on the larger tides, so check the tide height before you drive out — a small neap tide can leave the run-through as a trickle. Weekends and school holidays are busy; dawn, dusk, night and weekdays are the quiet windows. Keep lines clear of kayaks and paddleboards on the lake. Bag your scraps and put them in a bin, never in the water or on the bank. Fish lost to the bridge pylons and rock bar are the toll the lake charges for a run-through bite, so bring spare leaders.

Causeway Lake is on the Scenic Highway between Yeppoon and Emu Park. There is parking beside the bridge and the foreshore, with shaded tables and seats, barbecues, play equipment and a fish and chip shop. The lake edge is flat and easy for families, though the rock bar at the mouth is uneven and slippery. Kids are well catered for on the lake side, as long as an adult stays between them and the water.

The mouth faces the open sea, so a strong north-easterly or a big swell pushes waves over the bar and makes the seaward side unsafe; the lake itself stays calm in almost any wind. The bigger the high tide, the stronger the run-through and the better the fishing. Clear water favours the lure fish; after rain the lake discolours and bait fishing for bream and grunter takes over. Night fishing on the top of the tide is a local favourite for jacks and barra in season.

Causeway Lake is in crocodile habitat. Stay at least 5 m back from the water's edge where you can, never stand in the water to cast or to free a snag, don't stand on logs or branches over the water, and only throw a cast net from a boat or jetty. Reel fish in quickly and step back, and cut the line if a crocodile takes interest in your catch. The rock bar is slippery and the run-through current is strong — keep children off it. Marine stingers, including box jellyfish and Irukandji, occur in these waters, typically November to May; carry vinegar. Shark control equipment operates off neighbouring Mulambin Beach — stay more than 20 m from nets or drumlines; it's an offence to be inside the 20 m zone.

On the bigger high tides, when the sea spills over the rock bar and runs through under the bridge. Early morning, late afternoon and night are the quieter, more productive times, especially away from weekends and school holidays.

Barramundi, mangrove jack, trevally and queenfish come in on the run-through, and bream, grunter, estuary cod, flathead and whiting live in the lake. Barramundi are closed from 1 November to 31 January.

The lake side of the bridge is calm and shallow, with shade, barbecues and play equipment nearby. It is still crocodile habitat, so keep children back from the water's edge and off the rock bar during the run-through.