The Otago Regional Council works on flood defenses that are best suited to the area.
Flood protection schemes are designed to mitigate the risk of flooding to help protect people and their livelihoods.
Land drainage schemes are designed to provide ongoing, effective and reliable drainage of farmland.
Currently, beyond the flood protection schemes and land drainage schemes, ORC also has a combined flood and drainage scheme and a river control scheme.
The Alexandra Flood Protection Scheme serves as a robust defence against the high flows of the Clutha and Manuherikia rivers, shielding the township from potential floods and safeguarding approximately 10 hectares of land.
The Water of Leith rises in north Dunedin, and flows 14km through the city. It is a stream with the potential to inflict serious damage to property on the floodplain.
The Lower Clutha Delta Scheme mitigates flooding and drains 9,300 hectares from north of Balclutha to the sea. The Clutha River, splitting into Koau and Matau branches, and other water sources contribute to the flow
The Lower Taieri Plain has a long history of flooding, and development of drainage and flood protection works goes back to the early 1900s.
Stoney Creek in Wānaka flows into Lake Wānaka over an alluvial fan. Natural and engineered solutions are being developed to protect the area.
The East Taieri Drainage Scheme, divided by Silver Stream, directs northern drains to the Upper Ponding area and southern drains to the Lower Ponding area. Low Taieri River flow uses gravity drainage; high flows need pump stations.
The West Taieri Drainage Scheme, part of the Lower Taieri Flood Protection Scheme, is bordered by the Taieri River, Lake Waipori, and the West Taieri Contour Channel. Unlike other schemes, it relies entirely on pump stations at Waipori, Henley, and Lake Ascog due to its low elevation, often at or below sea level.
The Tokomairiro Drainage Scheme protects low-lying farmland around Milton from flooding. Located in a flat basin surrounded by hills, it consists of open drains, culverts, and bridge crossings, but has no pumps or control structures. Many drains were once creeks that have been realigned.
The Lower Clutha Delta Scheme mitigates flooding and drains 9,300 hectares from north of Balclutha to the sea. The Clutha River, splitting into Koau and Matau branches, and other water sources contribute to the flow
The Lower Waitaki River Control Scheme maintains braided channels and prevents erosion through groynes and riparian plantings. Three floodways convey flows from foothills to the river separately.
Learn about our flood repair programme for affected communities after a flooding event.
As well as maintaining flood protection and drainage schemes, ORC maintains some river channels by managing vegetation and monitoring and mitigating erosion.