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Sand Bypass System

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The Sand Bypass Trial is being carried out to establish if sand pumps located either side of the entrance will collect and relocate sand away from the entrance and how efficiently this happens.

This will be measured by a variety of surveys and other monitoring equipment that is being installed as part of the sand management program.

The Sand Bypass Trial will commence when all approvals and permits are in place.

The trial will use 18m sand shifters which will be installed at a location adjacent to the training walls on both the east and west sides of the entrance. These are installed under the surface where sand is collected and pumped through a series of pipes to the existing Sand Transfer Station. The sand will then be pumped to the onshore disposal sites approximately 1400metres from the training walls in both directions.

By removing the sand close to the end of the training walls, the problem of sand accreting around the wall ends and moving into the entrance channel will be substantially reduced.

It is planned to install pipes under the entrance channel to allow bi-directional pumping. This will allow sand being transported along the beach to be collected by a sand shifter on the approach side of the entrance and be pumped under the entrance to be discharged at some distance on the departure side. This can occur in both directions.

This will reduce the amount of sand that is transported across the entrance. It is the sand that crosses the entrance that is drawn into the channels by the tide that causes the accretion. Thus it is hoped the bi-directional bypassing will reduce the sand entering the system and in turn assist in the reduction of the bar.

Permits are required from Heritage Victoria, Parks Victoria and the Department of Sustainability and Environment to allow this proposal to proceed.

Environmental studies and heritage studies (both pre and post European settlement) have been undertaken to ensure there are no adverse consequences and to assist in the permit process.

A sand shifter was installed on the eastern side of the entrance in September 2007 and continued working until February 2008 when the 'Pelican' commenced its trials. It was deemed inappropriate to have both the sand shifter and the Pelican operating together as this could distort the monitoring of the Pelican trial. Now that the Pelican trials have concluded, the Eastern Sand shifter has once again commenced operations to reduce the amount of sand build up on the east side of the eastern training wall.

It is planned to have the bypass system fully operational by May 2009.

Sand Shifter - Sand Bypass Trial