Central Coast Council has been dredging The Entrance channel to Tuggerah Lakes estuary, on behalf of the NSW Government, for the past 25 years.
Council conducts this work to maintain the exchange of water between the estuary and ocean which offers benefits including:
- preservation of existing ecological values of the estuary
- reduced flood risks to life and property in low-lying areas around the estuary
- enhanced navigation within The Entrance Channel.
Dredging is only undertaken when a set of indicators are reached, which is why dredging is not required every year, with the most recent programs undertaken in 2015 and 2018.
These indicators also help to save rate payers money by ensuring unnecessary works are not undertaken.
Dredging indicators include:
- the throat of the channel (near the southern tip of the sand spit) at The Entrance reduces to an estimated width of less than 15m measured at mid tide level. Estimation of this measurement has been assisted by the instalment of a camera to monitor The Entrance.
- the flood tide sand shoals threaten to block the ebb tide dominant channel along the northern/eastern side of The Entrance area.
- the flood tide sand shoals threaten to block the main channel east of the bridge.
Council successfully moved approximately 45,000 cubic meters from The Entrance in 2018 which saw The Entrance, North Entrance and Karagi Point beaches benefit from sand nourishment as a result of the dredging program.