The Chatham Islands have nine known species of native freshwater fish. It’s important that instream structures such as culverts and weirs are designed to allow for fish passage, so that fish can move upstream and downstream between different river and stream habitats and complete their lifecycle.
Culverts, weirs, flap gates, fords and dams(external link) installed after 3 September 2020 must meet minimum reporting requirements such as height, width and location under the Essential Freshwater regulations. Culverts, weirs and flap gates must meet minimum environmental conditions for fish passage and may need a resource consent.
While the new regulations do not apply to instream structures installed before 3 September 2020, it is still important to ensure those structures provide for fish passage. There are options for remediating or retrofitting structures to help fish passage.
The New Zealand Fish Passage Guidelines (PDF file 8.7 MB)(external link) set out how to design instream structures that allow for fish passage.
Under national and regional rules, the installation, alteration, maintenance and removal of some structures is a permitted activity – and therefore does not require resource consent – only if you can meet the specific requirements outlined on this page.
Rules for fish passage
The National Environmental Standards for Freshwater 2020 (NES-F) (external link)(external link), introduced new national regulations for fish passage to be considered alongside regional rules in the Chatham Islands Resource Management Document (CIRMD).
These rules apply to all new instream structures, both temporary and permanent.
There are two main requirements under the NES-F.
- All new structures must be designed, installed and maintained in a way that will facilitate fish passage. Specific design criteria for weirs and culverts must be followed.
- You will need to provide information about the structure to us within 20 days of installation in accordance with NES-F Regulation 62.(external link)
Details on what information you will need to provide us depend on the type of structure and are outlined in the following sections.
For more information on how to collect and submit information to us, see "Reporting back to us".
Rules for structures
The following national rules apply if you are carrying out works to install or maintain a temporary or permanent structure.
- Permitted activity conditions for culverts (NES-F Regulation 70(external link)).
- Permitted activity conditions for weirs (NES-F Regulation 72(external link)).
- Consent requirements for passive flap gates (NES-F Regulation 74(external link)).
The following regional rules are covered in Rule 5.3.4, item 22 of the CIRMD and apply if you are carrying out works to install or maintain a temporary or permanent structure.
- Permitted activity conditions for installing, altering, extending or removing culverts, weirs, flap gates, fords and dams.
- Permitted activity conditions for the damming of water in the bed of a river or lake.
- Permitted activity conditions for installing, altering, extending or removing defences against water.
- Permitted activity conditions for maintaining instream structures.
- Permitted activity conditions for temporary structures and diversions associated with work on instream structures.
- Permitted activity conditions for monitoring or sampling equipment associated with work on instream structures.
- Permitted activity conditions for discharges to water when working on instream structures.
If you cannot meet any of these requirements, you will have to apply for resource consent.
Reporting back to us
When installing a structure in a waterway, you must provide information about the structure to us within 20 days of it being installed. Information must be provided for both permitted and consented activities. All of the information can be collected and submitted to us using the Fish Passage Assessment Tool (FPAT)(external link), a mobile app maintained by NIWA that is free for anyone to use.
Examples of the information commonly required include:
- The type of structure
- Physical characteristics of the structure
- Physical characteristics of the stream the structure has been installed within, such as the flow
- The likelihood of the structure to prevent fish passage
- Visual evidence both upstream and downstream of the structure.
See the links provided under the rules for each type of structure for the specific information requirements.
If you have any questions about the new Essential Freshwater regulations, contact us on 03 3050 033.