Fitzroy Barrage Tidal Lock Monitoring 2025-2026

The new Fishway on the north bank of the Fitzroy Barrage represents a major leap forward in tidal fish passage design. Developed in close collaboration with AFPS, this innovative structure combines two fishway systems within a single configuration, enabling larval, juvenile  and adult fish to move upstream with far greater success.

Purpose‑built for the Fitzroy River’s 5–6 m tidal range, the fishway uses a timed lock‑gate sequence to maximise passage opportunities. As the tide rises, the lock gate opens to attract fish into the cone fishway, allowing larger species to ascend, while juveniles enter once the lower cells are submerged. As water levels continue to rise, the steps between cells diminish, supporting juvenile progression upstream. After the tide peaks, the lock gate closes to create an artificial high tide within the fishway, slowly equalising with the upstream pool and allowing even the smallest fish to complete their migration.

Monitoring since the fishway became operational has recorded just under 57,000 fish (over 18 days) from 20 species, ranging in size from 8 mm to 700 mm. The catch has been dominated by the larvae and juveniles of empire gudgeons, bony bream and mullet. Successfully passing these early life stages is critical for maintaining the ecological health and long‑term productivity of the Fitzroy River.

The TideLock Fishway complements the two long‑standing fishways on the south bank, which have served the system for decades but are less effective for larvae and the smallest juveniles. By filling this critical gap, the new fishway significantly enhances ecological connectivity across the barrage and supports a broader range of species and life stages.