The purpose of this project was to stabilise the critical flood protection bank at four locations along Riverbank Road in the Lower Clutha delta, near Balclutha.
While flood events had damaged the flood protection bank in the past, the February 2020 further exacerbated the damage, eroding away parts of the floodbank and causing scour, slips and collapses of the floodbank at a number of locations.
At Riverbank Rd near Renton Rd, parts of a Clutha District road that provide public access to local farmers had collapsed into the river. Riverbank stabilisation was required over a length of 170m to prevent further collapse and to stop the river from damaging the flood protection stopbank on the land side of the road. At Riverbank Rd near Lawson Rd, the road is on the land side of the flood protection stopbank, however the river has eroded into the flood protection bank itself and stabilisation was required over a length of 90m. The focus of this project was to:
- Maintain the previous level of flood protection
- Provide stability to the flood protection bank
- Reinstate the public access road
Without these improvements, the stopbank would have been at risk of failure, leading to inundation of 9,300 ha of valuable agricultural land. The completion of this project has enabled ongoing productive activities on the land.
Repair works included:
- Stopbank reshaping and riparian planting
- Riverbank stabilisation using layered rocks and revegetation
This project was completed in mid-May 2021, and is awaiting completion certification.
Cost: $1 million