Completing flood protection project

A digger is used this week to build the last of four rock groynes on the north side and upstream of the State Highway 1 Waitaki River bridge to give greater flood protection to the highway approach.

A main braid from the river had been flowing along the north side, cutting into the bank just upstream from the bridge and threatening the abutment.

The NZ Transport Agency started on April 16 to improve the flood protection, using the four groynes to direct the flow away from the bank.

The groynes extend up to 25m at right angles from the river bank, using about 2000 tonnes of rock.

Acting Otago-Southland state highways manager Ian Duncan said if the work was not done, continuing erosion could threaten the northern bridge abutment, making it more vulnerable to flooding.

Resource consents for the $150,000 project were granted by Environment Canterbury and Waimate District Council.