U:\2021\BM210482_IBo_Waihi_North_Project\Documents\WNP_Freshwater_Report_May_2022\FINAL_Freshwater_Report_FOR DELIVERY_June 2022\FINAL DELIVERED 17 JUNE 2022\WAI-985-000-REP-LC-0007_Rev0_Freshwater_20220621_FINAL.docx • Fish and kōura should be salvaged from all watercourses containing water at the time of streamworks. • Peak fish migration occurs between September and February and streamworks should be avoided during this time if practicable. 22.2.3 Fish passage A number of migratory fish species are present within the footprint of works including swimming and climbing species. It is necessary to maintain fish passage through culverts to upstream and downstream habitats. The following remediation is recommended: • Fish passage should be maintained through all culverts with viable upstream habitat. • The type of fish passage (i.e., climbing or swimming species) required for each permanent culvert should be assessed by a freshwater ecologist. At a minimum all culverts should allow for the movement of climbing species if suitable habitat is present. • Fish passage to be designed based on NZTA guidance and New Zealand Fish Passage Guidelines (NIWA 2018). • New culverts are to be designed to incorporate fish passage, where upstream habitat is identified • In culverts with steeper gradients fish passage devices such as baffles may need to be considered. • Consideration should be given to restricting the potential passage of pest fish species if they have been recorded within the stream reach. • Temporary culverts shall maintain fish passage through them, allowing swimming fish species and other aquatic invertebrates to move through the culvert up and downstream, if appropriate. • The exclusion of trout from the upper reaches or non-preferable tributary streams will provide benefit for native fish and fauna (e.g., Stream TB1). 22.2.4 Trout fishery The Ohinemuri River is classified as a significant trout fishery, and there are important trout spawning tributary streams (including the Mataura Stream) as well as streams providing habitat for juvenile trout populations (including the Ruahorehore Stream). We recommend that passage and habitat (including spawning gravels where appropriate) for trout be included in the design of the lower reaches of diversions planned for Ruahorehore Stream. Passage for trout to the upper reaches of the Ruahorehore Stream diversions is less likely to be achievable and less desirable, thus providing more habitat for the native fish fauna. Diversion of waterways Proposed stream diversions across the project must meet ecological objectives and have good ecological functionality, especially if they are considered as part of an offset. The design of diversions will follow a hierarchy of avoidance of effects as much as practicable, and design to minimise effects. The following is recommended for stream diversions:
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