Rock protection work along the true right bank of the Mataura River at Mataura is about to start.
Last year, while a geophysical report found there was no obvious structural damage to the stopbanks on the Mataura River as a result of the 2020 flood event, river engineers raised concerns about a 600m section along the true left bank in the Mataura township that was at risk of erosion.
This work was prioritised and completed in March, while work on the true right bank was planned to be completed in the 2023-24 construction season.
Environment Southland integrated catchment management general manager Paul Hulse said recent flooding had increased erosion in the area and it wanted to get the work under way as quickly as possible.
About 32,600 tonnes of rock would be used to protect a 710m stretch of river bank along the true right, and was expected to take about four months to complete.
While the protection work was under way, community safety was paramount.
"Heavy vehicles will be moving in the area around the Alliance Group Mataura Plant, so please take extra care.
"In terms of flooding potential, our message to the Mataura community remains the same: be prepared to evacuate your homes at lower river flows than you might have in the past, and at short notice."
Emergency Management Southland would make any decisions about when and if to evacuate and would lead any evacuation. Each situation would be assessed on a case-by-case basis, as it was not possible to predict conditions for every situation.
In addition to the Mataura protection work, construction on a new stopbank along Ontario and Toronto Sts in Gore to replace the existing concrete flood protection wall was under way.
Gravel from the gravel island downstream of the Mataura bridge and would be used in the new Gore stopbank construction.
"It is great to be able to deliver two infrastructure improvements at the same time, repurposing gravel that would not normally be utilised.
"The council has worked closely with Hokonui Rūnanga to prepare a plan to remove the gravel as the Mataura River is a mātaitai reserve and an important spawning area for kanakana."
