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Checklist for Consenting In-Stream Fish Passage

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. The regulations have been introduced because many of our fish species have a migratory stage in their lifecycles, and structures in waterways can impair fish passage and contribute to declining fish populations: in New Zealand 76% of indigenous freshwater fish species are currently threatened with extinction or at risk.




Did you install your culvert prior to September 2020?

Any existing structures in a river or connected area prior before 2 September 2020, are not subject to the NES-F. This exemption includes alterations or extensions to the original structure.


Your culvert is a permitted activity and you do not need consent if:

The culvert provides for the same passage of fish upstream and downstream as would exist without the culvert

The culvert is laid parallel to the slope of the bed of the river or connected area

The mean cross-sectional water velocity in the culvert is no greater than that in all immediately adjoining river reaches

The culvert’s width where it intersects with the bed of the river or connected area (s) and the width of the bed at that location (w) — both measured in metres — comply with:

(i) where w ≤ 3, s ≥ 1.3 × w; and

FOR EXAMPLE: If you have a creek that is 1.2m wide (‘width is equal to or less than 3m’), then 1.2m x 1.3 time the width of the waterway = a culvert size of 1560mm ID (inside diameter) with at least 25% of this pipe buried below the surface of creek/waterway bed this will not require resource consent. If you want to install a culvert smaller than calculated by the formula, you would need to apply for resource consent.

(ii) where w > 3, s ≥ (1.2 × w) + 0.6

The culvert is open-bottomed, or it is placed so that at least 25% of the culvert’s diameter is below the level of the bed

The riverbed substrate is present over the full length of the culvert and stable at the flow rate at or below which the water flows for 80% of the time

The culvert provides for continuity of geomorphic processes (such as the movement of sediment and debris).


If your culvert does not comply with the requirements on this checklist, your culvert requires a resource consent to install and use the culvert. It is important to note that some councils/regional authorities set additional requirements for structures in rivers and streams — these can differ from the NES-F regulations.


For more information, see the Ministry for the Environment’s guidance on fish passage:

Or for a summary of compliance requirements, check out this poster from the Ministry for the Environment: 


Download the white paper here.