Future proofing flood protection infrastructure in line with national legislation means fish passage remediation is a priority for Environment Canterbury. Over 2022 and 2023, they’re making over a dozen instream structures more fish friendly.
The Essential Freshwater Package was introduced in 2020, requiring fish migration capability for all new structures built in waterways. Environment Canterbury was already looking at ways to alter existing flood protection and drainage scheme structures throughout Canterbury/Waitaha to make them more fish friendly while maintaining their integrity for flood protection.
Thanks to the one-off funding from Central Government, they have been able to use the opportunity to kick-start works across the region.
More than 15 sites are undergoing alterations to their structures. Regional monitoring was undertaken by staff across the organisation. The upskilling for these teams is also a key outcome from the project, to ensure all future structures meet EFP requirements. The fish passage work will protect or enhance travel for up to 14 species of fish/ika, including native taonga species tuna (long and shortfin eel) and īnanga/īnaka (common galaxias).
Fish passage is important as many of New Zealand’s freshwater fish need to move between habitats to support their different life stages and ecological needs such as spawning, rearing young, feeding and finding refuge. Many fish species need to be able to climb, whilst others need safe places to rest when swimming large distances.
Environment Canterbury undertook an assessment of 44 structures within awa/river and drainage rating districts and have focused on remediating structures that have a high chance of blocking most or all ika/fish movement most or all the time. Monitoring and evaluating will happen once works are completed, with Environment Canterbury incorporating fish passage into their business-as-usual work programme.