Byron Shire Council will manually open the mouth of Belongil Creek tomorrow after a failed attempt to clear the creek naturally.
Earlier this week, Council brought in an excavator to scrape back the sandbar – which has stopped the creek flowing into the ocean – in the hope the creek would release by itself.
Council’s Infrastructure Planning Coordinator, James Flockton said the attempt failed, leaving the sandbar still acting as a dam, preventing water from escaping and causing inundation in some areas of the floodplain.
“The water level in the Belongil is currently very high (1.32m) and rainfall predicted this week will increase the risk of flooding the catchment,” said Mr Flockton.
He said manually opening the creek was a last resort as it increased the risk of a fish kill. The work is planned for tomorrow.
“Belongil Creek, and nearby Tallow Creek, are extremely sensitive ecosystems and while our responsibility is to manage these waterways to mitigate flooding in the catchment, our aim is to have as little impact on the environment as possible,” Mr Flockton said.
“One of the big problems is that when a sandbar is opened there is often a very fast release of water from the creek and this can cause a fish kill.”
He said the higher the water level behind the sand bar, the greater the risk of flooding in the catchment.
“Allowing the water to continue to build up behind the sandbank and spread across the floodplain means the water is poor quality because of decomposed vegetation like grass and this then flows quickly down the creek and also increases the risk of a fish kill,” Mr Flockton said.
“We are hoping that the wet weather will help reduce the chance of a fish kill – that’s the last thing we want to see.”
Belongil Creek and nearby Tallow Creek are ICOLLs – intermittently open and closed lagoon systems.
Council has been continuously monitoring the water levels and is in regular communication with authorities including the NSW Department of Primary Industries and Environment and the Marine Parks Authority.
“We have communicated to all agencies to let them know we are going to open the sandbar,” Mr Flockton said.
Tallow Creek is also closed to the ocean and staff are closely monitoring water levels, the sandbar and rainfall predictions.
Information about Tallow Creek and Belongil Creek is on Council’s website.