The existing contour channel is part of the Lower Taieri Flood Protection Scheme.

The contour channel provides flooding protection and water conveyance to the Waipori Pump station, protecting 7,300ha of highly productive agricultural land surrounding communities and the Dunedin International Airport at risk from flooding in high rainfall events.

Stage 7 of floodbank reconstruction underway.

ORC’s Team Leader, Project Delivery Brett Paterson says the Contour Channel intercepts runoff from various steep streams located on the Maungatua Range and conveys the runoff by gravity to the Waipori River.

Lower Taieri Flood Protection Scheme & East/West Taieri Drainage Schemes, including Contour Channel.

He notes use of the Contour Channel floodbank goes back more than a century, as it was originally constructed in the early 1900s, using horse and cart construction techniques. This stage of the upgrade works consists of reconstruction of a 2.4km section of the floodbank and bridge upgrades within the section. The work carried out will provide present-day construction standards which improves the resilience to the floodbank.

Contour Channel upgrade largest within the ORC’s Climate Resilience Programme

Mr Paterson says the Contour Channel upgrade is the biggest package of work within the ORC’s Climate Resilience Programme.

The work was tendered last October. Contractors have now been engaged and construction is now underway. The work will be staged, with construction taking place during the summers of 2023 - 2025 to mitigate negative environmental effects.

The project is scheduled to be completed in 2025, Mr Paterson says.

The project is co-funded by Otago Regional Council and Central Government, through Kānoa (the Regional Economic Development & Investment Unit within the Ministry of Business, Innovation and Employment), says Manager Engineering Michelle Mifflin.

The cost of the overall upgrade is $5 million, with the Ministry for Business, Innovation and Employment funding $3.2 million and ORC $1.8 million as part of central government’s 2020 budget, which included $210 million for climate resilience and flood protection projects across New Zealand.

The Climate Resilience Programme has been an important funding boost to key infrastructural projects for Otago.

It has been through a successful campaign in collaboration with Regional Councils nationally, to receive a tranche of funding from MBIE, through Kanoa, that has really benefited long standing projects and recent resilience works which have resulted from flooding events since 2020, she says.

The working relationship between the ORC and Kānoa has been successful and created a good foundation for future funding opportunities from Central Government, she says.

Background of Otago’s flood schemes

Otago, the country’s second largest local government region, has seven flood schemes to protect about 43,000 hectares, with 218 kilometres of flood banks, 14 pumping stations, 55 bridges and other assets.