Construction of the Mardi to Warnervale Pipeline commenced in April 2020.
This $61million project is an integral piece of water supply infrastructure for the northern part of our region. It will service expansion in the major northern growth corridor including Warnervale Town Centre and numerous greenfield subdivision sites within the Kanwal Reservoir Catchment.
It will also improve drought security via bulk water transfers between the Central Coast and Hunter. The project will be delivered by joint venture partners Spiecapag and Seymour Whyte.
The Mardi to Warnervale Pipeline (M2WP) will provide a bulk water transfer main across the north of the Central Coast. The pipeline will run from the existing Mardi Water Treatment Plant to Sparks Road at Warnervale.
This vital piece of infrastructure will boost water supply to the rapidly growing Warnervale Town Centre and surrounding areas. The pipeline will also enhance existing inter region transfer capacity, increasing water security for the Hunter and Central Coast Regions.
View the pipeline on our interactive map below:
May-June Project Update:
July Project Update:
Where is the Mardi to Warnervale Pipeline located?
The Mardi to Warnervale Pipeline (M2WP) is a proposed drinking water pipeline that will run from the existing Mardi Water Treatment Plant through to Sparks Road at Warnervale. The pipeline will be nine kilometres long and 1000 millimetres in diameter.
The pipeline tunnel will run north from the Mardi Treatment Plant, under Deep Creek to Collies Lane, before turning east to cross below the M1 Motorway and then along Mardi Road. The pipeline tunnel will then turn north again, running beneath Wyong River, Alison Road and Porters Creek and continue north to wrap around the edge of the Watanobbi Estate. A final section of the pipeline tunnel will run at a significant depth below the wetlands before continuing north along the proposed ‘Link Road’ to connect with the existing water mains at the intersection of Sparks Road and Albert Warner Drive.
Why is the M2WP important?
Numerous planning studies have confirmed the pipeline is an integral piece of water supply infrastructure for the northern region of the Central Coast. The pipeline was identified to deliver two key functions:
Service growth in Central Coast Councils northern areas which include the State Government identified Northern Growth Corridor and the ‘Warnervale Town Centre’ Strategic Centre.
Improve drought security via increased bulk water transfers between the Central Coast and Hunter – up to 30 megalitres a day (12 Olympic swimming pools).
What are the expected benefits of the pipeline?
The M2WP will provide the higher operating pressure required to service elevated areas and emerging low pressure areas within the northern water supply network (including Warnervale Town Centre) allowing reduced reliance on booster pump stations and increasing the efficiency of the water supply system.
The pipeline will provide opportunities for the Hunter and Central Coast regions to further work together on options to build drought resilience.
How will the M2WP help water security resilience for the Central Coast and Hunter regions?
The Hunter and the Central Coast have very different water supply systems. This allows each system to help the other in different circumstances.
In general terms, Central Coast Council has slightly better storage but Hunter Water has a better ability to capture water.
During periods of drought, the most drought-affected region will receive water from the system that is less drought-affected. As the water levels of both systems decrease less water is transferred and if both systems are equally drought-affected then water transfers stop.
How has the environment been considered in this project?
Council has continuously considered the environment throughout the planning and design stages of the M2WP and has taken a range of actions to minimise environmental impact.
Extensive environmental investigations have been undertaken over the past three years, adding to Council’s existing understanding of the local environment obtained from previous infrastructure developments such as the Mardi to Mangrove Link Water Project.
This information has allowed the project team to select the most appropriate methods for constructing the pipeline whilst minimising environmental impacts. These methods include tunnelling the pipe significantly below the more sensitive environmental areas such as the Coastal SEPP Wetland north of Watanobbi and the sensitive riparian areas of Wyong River and Porters Creek.
What environmental assessments were carried out to develop the project? Where can I view these?
Extensive environmental investigations and surveys have been undertaken as part of the projects planning phase. Multiple ecological surveys and impact assessments of the pipeline corridor have been completed to ensure minimal impact on the environment. As a result of the surveys undertaken, further investigations and detailed management plans have been completed to ensure the protection of the Wyong cryptic flora species and the Watanobbi flying-fox colony.
Other surveys and impact assessments have included aboriginal heritage, noise and vibration, and soil and hydrology. All assessments have been incorporated into the Project’s Review of Environmental Factors (REF).
What are the trenchless methods that are being used?
A number of different trenchless methods will be used to construct the pipeline.
It is proposed that Micro Tunneling will be utilised for the M1 motorway and Deep Creek Crossings. Micro tunneling is a digging technique to construct small tunnels or in the case of our project used to install casing and pipe.
Will all of the impacted areas be restored?
Reinstatement works will be completed by experienced and qualified horticulturists who will be responsible for revegetating any disturbed areas. These works will occur as soon as practical after the pipe has been laid.
Before construction begins a dilapidation survey will be completed. This process involves capturing a detailed photographic record of land condition prior to construction. These records provide valuable information to allow the project team to restore the land to its former condition and in many cases to a better condition due to the reduction of weed species.
If my property could be affected, who can I speak to about this?
Directly affected property owners are those whose land is within the construction corridor. All directly impacted property owners have been contacted. The project team continues to work closely with directly affected property owners, providing detailed information and answering any questions.
Other properties may be affected by noise, dust or vehicle movements during construction. If you believe you may be impacted by construction works you can discuss this with our project team via email or phone – M2WP@centralcoast.nsw.gov.au or 1800 413 841.
Who owns the land where the pipeline will be constructed?
The majority of the land within the pipeline
easement is Council owned and is contained within Council open space areas and
roadways. The remaining land that will be used is privately owned small rural
allotments within the Mardi area. The project team contacted owners of impacted
land in the Mardi area during the planning phase of the project and continue to work closely with these property owners.
I received information about this project in 2016 stating that the project would be completed by 2018, why has this not occurred?
The design stage was completed in 2018 following rigorous site investigations, design optimisation, and environmental investigations including flora and fauna studies along the optimised route. Council has secured a construction partner and works will commence in 2020 and be completed by 2022.
When is construction of the pipeline scheduled to start and when will it be finished?
Council will commence construction in 2020 and to have the pipeline operational in early 2022.
How is the Mardi to Warnervale Pipeline being funded?
The project is being funded by a combination of accumulated revenue and developer charges within Council’s water supply fund.
Can I still use my back gate that provides access to the reserve?
At this stage we cannot confirm. Wherever possible existing access routes will be maintained where safe and practical. Notification about any restrictions for access will be provided.
Where will workers access?
The design has highlighted possible points of access and these have been included and assessed as part of the Review of Environmental Factors.
Although it is unlikely these will change, the contractor may assess alternatives if conditions or environmental factors mean original points of access are no longer viable.
What are the working hours for the construction phase?
Normal working hours are:
· Monday to Friday 7am-6pm
· Saturday 8am-2pm
However special operations, such as the Horizontal Directional Drilling may require 24/7 operation due to technical constraints.
Where out of hours works are required, all reasonable measures to avoid disturbance will be implemented.
Will there be vibration, noise, dust?
Yes. The nature of the works will inevitably see the production of such, however under the contract the contractor must implement appropriate controls to mitigate in so far as reasonably practicable.
What changes will I see once the construction is complete?
One the areas are restored, the only visual indications will be:
· Maintenance pit covers along the pipeline at various locations where service valves will be located
· A 10m cleared grassed area or access track over the 10m pipeline easement
· Occasional short sections of unsealed access tracks for maintenance purposes
· Reduced weed densities due to the restoration goal of improving the disturbed areas through weed removal
· Tree line pulled back from property boundary only where required
· The Albert Warner Valve House building which has been architecturally designed and is located next to Lakes Grammar School.
How big is the pipe?
The pipe will be 1000mm in diameter with the exception of a small section of pipe at Nikko Road which will be 375mm.
Will the pipe be noisy when operating?
Once construction is complete, there will be no noise generated from the pipeline. The pumps used to transport the water through the pipe are existing units located at the Mardi Water Treatment Plant. The flow velocity will not cause any noise or vibration.
Periodic inspections and maintenance of the pipeline valves will be required as per standard Council maintenance of its assets.
How far from my property boundary will the pipeline be located?
This varies dependent on location, however the closest the pipeline’s centreline will be to a property boundary is 5m.
How long will it take to pass my property?
The works will be continuously progressing along the pipeline route, however due to the anticipated use of the construction corridor as construction access route, there will be activity in the area for a period of six to nine months.
Will Council be reinstating the area distributed by the pipeline construction?
Council owned areas: The contractor under advice from Council will be reinstating all disturbed vegetation fences, structures etc. to their original status as per prior to construction. The exception will be the 10m pipeline easement which will remain free of trees and shrubs as these may cause problems to the pipe from root system incursions.
Private properties: A dilapidation survey will be conducted (in consultation with the land owners) of the entire pipeline corridor prior to construction commencement. Council will use this information to ensure properties are restored to their previous condition.