Oyster reef trial bid to expand in river

Unitywater has submitted a development application to install two shellfish ‘reefs’ in a Moreton Bay river.

Unitywater Executive Manager Sustainable Infrastructure Solutions Mike Basterfield says the application is with Moreton Bay City Council for the ‘reefs’ to be placed in the North Pine River.

They would be placed at Lawnton Pocket Rd, Lawnton and Brickle Rd, Kallangur.

The ‘reefs’, are made up of 400sqmm triangular baskets which are filled with 18kg of recycled oyster shells sourced from restaurants and commercial shucking operations. They are designed to host species such as oysters, mussels and other molluscs.

The pre-seeded baskets are ‘soaked’ in Moreton Bay for about a year before being placed in the river. As they grow, the collective effects of the reef increase.

The two new ‘reefs’ would be part of a broader trial launched in 2023.

“A reef was installed in September 2023 as part of a four-year trial with University of the Sunshine Coast researcher Dr Ben Gilby in partnership with Unitywater, OzFish and Healthy Land and Water to measure the impact of shellfish reefs on water quality in the river,” Mike explains.

“This trial is measuring the nutrient reduction capability of shellfish, which naturally filter water when feeding.

“It is testing a number of parameters for the best growth conditions including the reef structure, water depth at high tide, and salinity level. Preliminary findings are due soon.

“This trial supports Unitywater’s commitment to sustainability and helps us work towards achieving our target of net zero nutrients to waterways by 2040.”