Project description
Isabella Weir has been upgraded, improving water quality in the Tuggeranong area, better preparing for rare flood events, and restoring the natural environment of Isabella Pond.
The upgrade brings the weir into line with national best practice guidelines, and the ACT Dam Safety Code.
The rebuild has included widening the weir, which has increased its capacity to accommodate major floodwaters and heavy rains. The labyrinth weir, which features a saw-tooth profile, enables more water to pass downstream and regulates the flow of water into Lake Tuggeranong.
The Isabella Ponds Wetlands Project, which was conducted simultaneously to the Isabella Weir Upgrade, established two wetlands to improve the quality of downstream waterways into Lake Tuggeranong, the Murrumbidgee River and the wider Murray-Darling Basin.
Through natural filtration, the cleaner, healthier waterways have also increased opportunities for recreational use of Isabella Pond, and attracted native wildlife and birds to the area.
The wetlands will remove over 462,000 kilograms of nitrogen, phosphorous and suspended sediment every year from urban stormwater destined for Lake Tuggeranong.
Construction of the two new wetlands at Isabella Pond was the first project undertaken for the ACT Healthy Waterways initiative, and the projects were combined to minimise impact on the local communities.