Marine Safety Tasmania has published a report titled “St Helens Barway Review & Update of Options“.
Coastal Engineering Solutions Pty Ltd (CES) was engaged by MAST to undertake a review of previous studies of The Barway at St Helens. The two primary outcomes required from the study are:
Provide an opinion about the navigability of the barway and the channels within the
entrance over the next five years without any intervention.
Provide recommendations of long term solutions for improving navigation at the bar
and entrance channels.
The report concluded that:
- Removal of sand from the beach to the east of the training wall is essential to prevent further build up of sand on the bars and shoals seaward of the training wall.
- St Helens will never be an all-weather port. The the limiting wave condition at The Barway for safe navigation is when the wave height in deeper water (7 metre depth) seaward of the bar is 1 metre. Even a channel depth maintained at -3 metres (LWD) may be difficult to navigate at times.
- Dredging of the barway can be undertaken using either agitation dredging or a suction dredge.
- Dredging of the shoals at Pelican Point can be undertaken using agitation dredging, sidecasting dredging with a suction dredge or by employing a small cutter suction dredge, if available.
- Environmental approvals would need to be obtained for any dredging operations.