Blue Mountains News

The concrete culvert that sits across Leura Falls Creek was damaged by numerous wet weather events over the past ten years, including a one-in-50 year rainfall event in 2020. This was then compounded by further flooding in 2021 and two natural disasters in 2022.

The damage caused by these weather events has been assessed, confirming the need for the total replacement of the concrete culvert.

Currently, Cliff Drive remains closed to vehicles due to the damaged culvert but is open to pedestrians and cyclists.

During the culvert replacement works, pedestrian and cyclist movements around the precinct will remain largely uninterrupted, outside of the fenced construction area, with paths and walking tracks unimpeded by the culvert replacement work. However, the flood lights in the lower part of the precinct will not be operating.

Blue Mountains Mayor, Mark Greenhill, said: “The journey we’ve been on towards the replacement of the old culvert has been complex, involving a range of critical geotechnical investigations, aerial surveys, slope stability studies and detailed plans including environmental impact management. I would like to thank the community for their patience as we’ve worked through this process.

“The culvert itself was likely constructed before the 1940s so there are no plans to pull off the shelf and review previous construction details. Add to that the instability of the area following the unprecedented rainfall of recent years, and we have a sensitive site that needs to be treated very carefully to ensure the best outcomes from both an infrastructure and environmental point of view.

“It’s also important to note that we’re not replacing like for like. The new culvert will be of a significantly larger capacity which will provide additional benefits for the creek line.

“The capacity of the old culvert has become insufficient over time, causing debris to build up and block the inlet, especially during storm events. This leads to detrimental impacts to the creek and results in more time spent on clearing and maintaining the culvert.

“Improving the water flow, both upstream and downstream from the culvert, and improving the health of the creek is an important outcome of this work.”

Given the scale of the culvert replacement project, some surrounding vegetation on the culvert embankment and within the work area will need to be removed to allow the necessary earthworks to take place. Vegetation removal will be restricted to the minimum extent necessary.

Tree ferns that are removed will be transplanted to a stockpile area on the upper lawn of the Leura Cascades precinct. Near the end of the project, when work to revegetate the culvert embankment takes place, these ferns will be replanted where appropriate.

During construction, this stockpile area at the cascades visitor carpark will be fenced-off for safety as it will also contain materials from the culvert work site.

“The environmental footprint of this project has been a key consideration from the outset and one of the reasons the work has been delayed is that we’ve been carefully assessing and discussing construction methods to ensure the impact is minimised as much as possible.

“However, when we’re replacing such a large piece of infrastructure, in a site such as this, its unfortunately unavoidable that the work will result in a level of disruption.

“After the new culvert is in place a great deal of work will also be undertaken to rehabilitate and revegetate the site. The Leura Cascades Precinct Plan is also progressing with new draft concept designs available for community review and feedback.

Council is also assessing options for the reopening of Cliff Drive to vehicles in coordination with the culvert works and precinct upgrade plans. 

“We know the community is interested in what this work means for Cliff Drive, as replacing the culvert is a significant piece of the work required to make the road safe for vehicles. We’re looking at how the culvert works and the wider precinct upgrade plans influence reopening timeframes and planning.

“Replacing the culvert is a complex project. It’s a critical piece of infrastructure that will enable Leura Cascades to better withstand extreme weather events and help safeguard the future health of Leura Falls Creek.”

The Leura culvert replacement is being funded by the Australian Government’s Black Summer Bushfire Recovery Grants Program.

More information about the Leura Culvert replacement project is available at: here

For more information on the Leura Cascades Precinct Plan and the draft concept designs, visit: here