The Lower Taieri Flood Protection Scheme mitigates the risk of flooding to the Taieri plains, including the townships of Mosgiel, Outram and Henley. It also protects critical infrastructure such as key transport routes (state highway and railway networks), Dunedin airport, and power and three waters infrastructure.

Along with the East and West Taieri drainage schemes, the Lower Taieri Flood Protection Scheme was the first to be developed in Otago – works started in 1870. It is a complex network affected by many rivers. The scheme uses ponding areas to detain peak flows and ease pressure on the scheme downstream, minimising the risk that the scheme will fail. Silver Stream, Waipori River and the Ōwhiro Stream are tributaries to this lower portion of the Taieri River.


Lower Taieri flood protection scheme


Lower Taieri risk assessment

The ORC commissioned a high-level risk assessment as part of a wider body of routine work to assess the performance of the Lower Taieri Flood Protection Scheme.

This report assesses risks associated with the floodbanks and identifies sections to be investigated further to improve the scheme’s resilience. The findings will help us prioritise potential floodbank improvements. They will also guide further assessments, give us a better understanding of the level of risk that can be tolerated, and inform adaptation plans.

The Lower Taieri Plain has a long history of flooding, and development of drainage and flood protection works goes back to the early 1900s.

The Lower Taieri Flood Control Scheme (Figure 1) provides flood protection to an area of approximately 18,000 ha of the Taieri Plain. The scheme provides important protection to what is predominantly a farming area, along with the townships of Mosgiel, Outram, Momona, and the Dunedin Airport. 

The land is very low-lying, with some West Taieri farmland being slightly below mean sea level.  Dunedin Airport is about one metre above sea level, and Mosgiel some 15m above sea level.