20 October 2026
At Leed, we aim to conserve and reduce the impact on the natural environments where our project works take place. This commitment is evident in our current works as part of the NSW Government’s Yanco Creek Modernisation Project.
One of these strategies has been to use cofferdams. A cofferdam is a watertight temporary barrier that isolates part of a live waterway. This allows construction to take place in dry conditions while helping protect the surrounding aquatic environment.
Our team is using cofferdams to construct new regulator structures to help manage flows across the Yanco Creek system. The project includes construction and remediation works at Wilsons Anabranch, Forest Creek, and Cheverells Creek.
As part of delivering the works our team has constructed two types of cofferdams:
- sheet pile cofferdams, like the one pictured below, which are made from interlocked steel, and work best for deep water and tight spaces
- earthen cofferdams, which are created from compacted soil and are the best option for slow moving water.
The temporary cofferdam in the photo is diverting flows at Wilsons Anabranch while the in the centre is completed.
Reducing the environmental impact of our construction activities extends beyond just installing cofferdams. In line with the environmental planning approvals for these works, other environmental mitigations include:
- installing a temporary bypass pipeline beneath the work area at Forest Creek to maintain continuous flows during construction
- altering the original construction zone at Wilsons Anabranch to protect a significant 200-year-old gum tree
- relocating native fish further downstream to allow construction at the three sites to take place
- carefully managing habitat near the worksites to minimise the impact on animals that call the Yanco Creek area home including wedge-tailed eagles, emus, wombats and kangaroos.
The Yanco Creek Modernisation Project is being delivered by the NSW Government with funding from the Australian Government, as part of the Sustainable Diversion Limit Adjustment Mechanism (SDLAM) Acceleration Program.
Image: Part 3A – Wilsons Anabranch
Read about our other environmental water infrastructure projects.