South Cessnock Flood Mitigation Construction
- Project typeFlood Mitigation Construction
- Project value$5,955,000
- Project scheduleSeptember 2023 - February 2025
Background
At the 20 May 2020 Ordinary Council meeting, Council adopted the South Cessnock Flood Mitigation Scheme which includes:
- Earth bund wall
- Raising of Quarrybylong Street
- Diversion of Kearsley Creek channel
- Raising of up to five properties
This project forms part of Council's Operational Plan. You can find it within the Operational Plan with the Project ID PMF-2022-006.
Scope of Works
- Construction of a bund wall - running along the eastern side of the railway line parallel to Sixth Street, as well as associated drainage structures
- Levee / road raising - a small levee parallel to and across Quarrybylong Street, plus raising Quarrybylong Street near Edgeworth Street
- Channel diversion and widening - downstream from the junction of the Kearsley Channel and Oliver Street Channel, including demolition and realignment of part of the existing cycleway nearby, including removal and replacement of the existing pedestrian / cycleway bridge.
Images
South Cessnock Flood Mitigation Scheme
Raising of Quarrybylong Street
Kearsley Creek Channel Diversion
Progress
Update: 4 December 2023
Bolte Civil have been engaged by Cessnock City Council to complete the initial stage of the South Cessnock Bund Wall Scheme involving stormwater channel widening at Railway Street. This project will include demolition works, earthworks, concreting and retaining wall construction.
Construction works are planned to commence from 6th December 2023 (weather permitting) with preliminary establishment, site survey and demolition works.
For your safety, Bolte Civil request that the traffic and pedestrian control conditions and signage are followed at all times.
Site construction works will be between 7:00am to 5:00pm Monday to Friday and 7:00am to 2:00pm Saturday.
Update: 8 March 2023
The pre-construction period is complete. This period involved an independent peer review, resulting in a formal verification of the design, which satisfied grant funding requirements.
However, compulsory acquisition of Crown land for construction/drainage easement purposes has stalled due to Aboriginal Land claims affecting two parcels. This is a complex process and could cause delays to the project. To keep the project running, we are suggesting minor changes to the basin outlet (and receiving watercourse) to avoid these two properties.
Consultants are already working to determine the design implications for the potential changes to the basin outlet and will complete the assessment by April 2023. All other components of the scheme will remain the same.
A landscape architect was engaged as part of the detailed design process to enhance visual amenity for the main scheme components, being the bund wall and the diversion channel.
The tender period will commence in April 2023 provided the alternative design is accepted.
Council has now engaged the NSW Public Works to project manage the tender and construction phases, as well as to assist Council in the finalisation of pre-construction activities.
Frequently Asked Questions
When will works commence?
The construction period is expected to commence by September 2023.
When will works be completed?
The project is scheduled for September 2023 – February 2025.
How much is the project going to cost?
$5,955,000 various grants and Council funds.
What are the stages of the project?
The project will be completed in 3 stages:
- Stage-1: Channel Diversion & Widening – 120 m long by 18 m wide, to be constructed from the junction of the Kearsley Channel and the Oliver Street Channel, and flow into the existing Hunter Water Corporation channel.
- Stage-2: Levee / Road Raising – a small levee running parallel to, and across Quarrybylong Street, plus raising Quarrybylong Street near Edgeworth Street.
- Stage-3: Main Bund Wall – 470 m long up to 4.3 m high, running along the eastern side of the railway line parallel to Sixth Street, as well as associated drainage structures.
What are the benefits of this project for South Cessnock residents?
South Cessnock has a history of flooding that has been made worse by mine subsidence of up to one (1) metre in the 1980s. In a 1 in 100 Annual Exceedance Probability (AEP) flood, 16 homes experience over floor flooding and 71 homes experience yard inundation.
The bund wall will create a storage basin to detain and slowly release flood waters, thereby mitigating the impacts of flooding in the South Cessnock area. The project also involves raising five (5) homes that would still be at risk of over floor flooding in a 1 in 100 AEP event.
Benefits of the scheme include:
- Will reduce design flood levels to pre-subsidence values.
- Lowers average flood depth 14cm relative to average pre-subsidence depth.
- No home will experience over floor flooding in a 1 in 100 AEP flood.
- Safe pedestrian access to all homes in 1 in 100 AEP flood.
Will there be any traffic changes/road closures through the duration of the works?
Yes, When completing stage-2 and Stage-3. This is something to be determined during the construction phase.
How can I get in touch with the project team if I have any questions?
You can contact council at 02 4993 4100 or at council@cessnock.nsw.gov.au.