Central Coast Council / Expression of Interest for Construction of the Mardi Mangrove Link Project - NSW Central Coast - CPA/159131

Wyong River Off-take Structure

A new river off-take, near the site of the existing structure, capable of extracting up to 500ML/day from the lower Wyong River.  This will be a reinforced concrete structure, with coarse screens, located in the river bank.

Wyong River Pumping Station

A new in-ground submersible pumping station (nominally 12m in diameter) to extract water through the Wyong River Off-take Structure, and to transfer it, via the Wyong - Mardi Rising Main No 3 to Mardi Dam, with an installed capacity of 320ML/day.

Wyong - Mardi Rising Main No 3

A new rising main, approx 2.1km long and about 1000mm diameter, supplementing two existing rising mains, to transfer water from the Wyong River Pumping Station to Mardi Dam (via the Wyong - Mardi Inlet.  The majority of the route will be through private property but there will be the need to cross the Old Maitland Road once and also to traverse a limited amount of Council property.  Construction will be by open trenching and will involve one pipe bridge.

Wyong - Mardi Inlet

A new inlet to Mardi Dam to take the flow from both the Wyong-Mardi Rising Main No 3 and from the Mardi - Mangrove Transfer Main.  The inlet will include a breaktank and a diffuser structure.

Mardi - Mangrove Transfer Pumping Station

A new pumping station to pump water from Mardi Dam, through the Mardi - Mangrove Transfer Main and the existing Boomerang Creek Tunnel, to Mangrove Creek Dam at a rate of up to 120ML/day. It will be located in the vicinity of Mardi Dam and will be above-ground and contained within a new building.

Mardi - Mangrove Transfer Main

A new pipeline, approx 19km long and about 1000mm diameter, linking Mardi Dam with the end of the existing Boomerang Creek Tunnel (which leads to Mangrove Creek Dam). It will permit flow in either direction according to operational needs.  The majority of the pipeline will be in private property and constructed using open trenching. However, there will be sections of the route where construction will take place in the road reserve of the Yarramalong Road and there will be a number of river crossings.

Boomerang Creek Inlet/Outlet Structure

Modifications to the existing structure in the Boomerang Creek arm of Mangrove Creek Dam to enable it to operate as an inlet / outlet structure.  Depending on dam storage levels, this could involve underwater work.

Lower Wyong River Weir, Fishway and Gauging

Modifications to the existing weir and fishway (downstream of the Wyong River Off-Take Structure) to incorporate a low-flow fishway and improved flow measurement capability.