Severe erosion on the banks of the Tweed River remains of concern as ongoing rain continues to impact water quality.
Council's waterways team is working on the rehabilitation of creek and river banks damaged by unprecedented flows in the February flood, while trying to accurately record the full scale of the damage.
Council's Waterways Program Leader Tom Alletson said significant work was required to restore and protect the river's banks across the length of the waterway.
"Erosion is significant in many locations along the Tweed River and will require a lot of work however, the most extreme damage is in the section of the river between Byangum and Uki," Mr Alletson said.
"The erosion at this stretch is beyond what we have experienced before and some reaches of the river bank have been stripped of trees and soil, receding by as much as 30 metres.
"We will undertake an assessment at each erosion site to determine where interventions will be most effective.
"The timeline for recovery will be long. All sections of the river bank require attention but some sites need to be specifically targeted to prevent erosion progressing, leading to additional problems downstream."
Work is underway to stabilise erosion on the river bank, downstream from Murwillumbah on Tumbulgum Road. The erosion here has progressively worsened since the 2017 flood, with further damage caused during the most recent flood.
Works will include placement of rocks to protect banks from flood flows and wake waves, with large logs incorporated to enhance fish habitat. The river bank will be fenced to exclude cattle, and revegetated with native trees. Work will take approximately 12 weeks with investment from the Commonwealth Government's Fisheries Habitat Restoration Program.
Council can provide advice and assistance in some cases for land owners seeking help with erosion, while River Health Grants may be available to improve river health, erosion remediation and revegetation.
Mr Alletson said water quality had been beginning to return to normal in downstream reaches of the river and coastal creeks, however the current wet weather would impact that process.
"It's important to use good judgement when accessing the water, as water samples taken on high tide may comply with swimming guidelines. However, the same site sampled at low tide, or further upstream beyond the reach of tidal flushing, may deliver poor results," he said.
Since the floods, rehabilitation has been focused on removing litter and debris, as well as salvaging and making safe damaged boating facilities. The Tweed River benefited from work undertaken by the NSW Environment Protection Authority (EPA) who assisted with the removal of litter and hazards.
Crews removed tonnes of debris from Bray Park to Fingal Head, including a 10-metre sunken boat, and two 'Return and Earn' reverse vending machines from South Murwillumbah.
Mr Alletson said Council gratefully accepted the assistance provided by the NSW Government.
"It's the first time we have received NSW Government assistance for this type of post-flood environmental clean-up and we are most grateful," Mr Alletson said.
"It has saved us months of work as well as reducing the risk of pollution and injury.
"As intense storms become more frequent due to the impacts of climate change, we need to increase the health and resilience of our waterways so they can withstand these kind of events."
