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Fish Passage Management

Fish Passage in New Zealand


Fish Passage management may look complex but it’s an important consideration when looking at water management on your land.


Culverts, weirs and flood gates are very common throughout New Zealand streams and rivers, but if these structures are not designed, installed and maintained correctly, they can disrupt fish lifecycles by creating barriers to fish passage and preventing fish moving up and downstream and to the sea.


The best time to consider fish passage is before a structure, such as a culvert, is built or placed in a stream.

Why do we need Fish Passage Guidelines?


The regulations have been introduced because many of our fish species have a migratory stage in their life-cycles, and structures in waterways can impair fish passage and contribute to declining fish populations. Poorly designed instream structures (including culverts, weirs and dams) are a significant contributing factor in the declining populations of New Zealand’s native freshwater fish: in New Zealand 76% of indigenous freshwater fish species are currently threatened with extinction or at risk.


Although the full Fish Passage Guidelines are extensively detailed at more than 200 pages long, there are some straightforward principles for good fish passage design – the critical advice is to: keep the stream bed and stream flow as similar to its natural state as possible.


To make it simple we have come up with a checklist to help you design in-stream structures that comply with fish passage regulations:


Resources / Case Studies

Fish Passage in NZ


Recently there has been an increased focus on protecting the future of New Zealand’s more than 50 species of freshwater fish. This increased focus means there is now a greater emphasis on compliance with regulatory requirements relating to fish passage – so civil engineers, landowners and farmers with waterways on their land need to familiarise themselves with the legislation and what it means for them.


EUROFLO® delivering durable, efficient installs


EUROFLO® is delivering durable solutions for projects in Ruapehu region. Adding to the complexity of the project was the Regional Council requirements that require culverts to be of a sufficient size and design to allow for unimpeded passage of fish.

fish passage culvert

Simple Solutions for Good Fish Passage


Fish passage guidelines look complex but this P&F Global white paper outlines the simple concepts you need to follow to design instream structures that comply with regulations.

EUROFLO on farm

Checklist for Consenting In-Stream Fish Passage


National Environmental Standards for Freshwater (NES-F) regulations now apply to a range of structures — including culverts — in New Zealand rivers, streams and connected areas. So how do you know if you need consent for your culvert in a river or stream?

Action for Healthy Waterways


Wetland protections and standards for intensive winter grazing are among the first of the new freshwater regulations to take effect. We’ve developed this short paper to provide an overview of all the freshwater regulations, and to outline what farms will need to address to comply and the timeline for compliance.


Inspired farmers take action to clean waterways


A catchment restoration project in the Marlborough Sounds is bringing a farming community together to tackle water quality issues and achieve wider conservation goals and EUROFLO® culvert pipe is providing simple solutions to remediate barriers to fish migration.

Working together to restore the biodiversity of rivers


Tiki Garton, who as well as being a farmer is a valued member of P&F Global’s Northland team, is now working with a range of other like-minded locals to identify practical, sustainable steps to help restore and preserve the biodiversity of the river running through their farm and support good fish passage.

Tasman District Council (TDC) Fish Passage Trials


As part of the Jobs for Nature Fish Passage Project, EUROFLO® culvert pipes were used in the trials. TDC is pleased to share that its latest publication on the efficacy of fish passage remediation methods, is now available. This comprehensive study offers valuable insights into the effectiveness of low cost culvert remediation techniques for enhancing aquatic connectivity.

Need more help?


Spending some time planning the design and installation of any new or modified instream structure is the key to ensuring it is compliant.


Talk to your local EUROFLO® stockist or contact our helpful team of experts today for their advice on the simplest solutions for an instream structure that meets all of the fish passage requirements:



On large culverts, visit our page on EUROFLO® Pipe


For further resources on fish passage management in New Zealand please visit the Department of Conservation fish passage webpages


Regional councils e.g. Tasman District Council Fish Passage project updates 


Fish Passage Assessment Tool has been developed by NIWA to provide an easy to use, practical tool for recording instream structures and assessing their likely impact on fish movements and river connectivity


The Ministry for the Environment has developed a range of fish passage assessment tool resources, including:





Department of Conservation (DOC)


National Institute of Water and Atmospheric Research (NIWA)


New Zealand Parliament Conservation (Indigenous Freshwater Fish) Amendment Bill 2018