The Hall Road Upgrade has 225 concrete culverts installed to help mitigate major flooding in the area.
Major Road Projects Victoria program director Brendan Pauwels said the upgrade was not just removing outdated roundabouts on Hall Road but also doing major works underground to mitigate flood events affecting the surrounding properties in Carrum and Cranbourne West in the future.
Upgrading the drainage throughout the area has been a major aspect of the Hall Road Upgrade and required the creation of immense drainage systems across the breadth of the project.
Installing the culverts, massive underground concrete channels to carry water away from major structures such as homes or roads, helps ease flooding events and take huge stormwater surges away from Hall Road and surrounding properties.
Each of these culverts weighs between one to eight tonnes.
Crews upgraded entire drainage systems to help mitigate flooding to the area by capturing and storing excess floodwater before releasing it slowly over time.
The ongoing works under the new eastbound lanes and recently completed works at Taylors Road will ensure that all rain downfall is able to pass under the road, and any rainfall run-off from the new lanes on Hall Road is stored and gradually released.
These culverts working in tandem with existing stormwater drainage systems in the region as well as the seven retention basins installed across the project will hold up to a total of seven million litres of water, equivalent of over two-and-a-half Olympic swimming pools.
The largest retention basin is located at Western Port Highway and Hall Road, and can hold 2.5 million litres.
It was installed August 2023 and stores water runoff from traffic lanes before slowly releasing it into the stormwater drainage network.
Another retention basin was built at the intersection of Hall, Evans and Cranbourne-Frankston roads in June 2023 and measures 4000 square metres and can hold up to 1.9 million litres.
