Slacks Creek is a highly urbanised catchment in the City of Logan in south east Queensland (SEQ). Logan City Council (LCC) developed the Slacks Creek Recovery plan in 2013 which aims to improve the health of Slacks Creek while also enhancing the open space values.

Urbanisation in the catchment has led to the construction of culvert road crossings across Slacks Creek. These culverts form barriers to fish migration resulting in the upper catchment being a depauperate in diversity and abundance of native fish species.

Following results from the Greater Brisbane Fish Barrier Prioritisation project, the Paradise Road culverts were identified as the first fish barrier remediation project to be undertaken in Logan.

LCC engaged fishway specialists Catchment Solutions Pty Ltd to design and construct a cost effective fishway through the culverts in 2016.

Prior to the construction, monitoring was undertaken to determine the number and species of fish currently able to pass through the Paradise Road culverts. A fish trap was set up on the upstream side of the barrier over a five day period. Following the construction the same standardised monitoring was undertaken to evaluate any changes in the number and diversity of fish now able pass through the culvert.

Pre-construction monitoring recorded a total of 18 individual fish comprising 5 species, over a five day period, able to move through the culverts. Post construction monitoring recorded 6,546 individual comprising 11 species (Moore. M and Resch. B, 2017).

The results from the monitoring clearly indicate that

1. typical culvert road crossing structures can have a high impact on the ability of native fish to migrate into upstream habitats; and,
2. remediation of barriers to fish movement through construction of simple, cost effective fishways can have a significant benefit to the diversity and abundance of native fish in urban creek catchments.