Lower Mehi River Fish Habitat Mapping

2rog Consulting was engaged by DPIRD to undertake aquatic habitat mapping surveys for the NSW DCCEEW – BCS Group along 170 km of the Mehi River in the Gwydir Catchment as part of the broader Gwydir Reconnecting Watercourse Country Program which forms part of the Northern Basin Toolkit designed to implement environmental works and measures identified in the Northern Basin Review.

Aquatic habitat mapping was undertaken to establish a baseline record of aquatic and riparian habitats in the study area. The project was required to determine priorities for protection and enhancement of aquatic and riparian habitats through a range of interventions including water management and aquatic habitat rehabilitation activities, landholder liaison and weed management.

The main objectives of this mapping project included the following: • Document the riparian features of the identified reaches of the Lower Mehi River, focusing on native vegetation, weed infestation and existing management activities. • Document the stream bed morphology including the location, length and depth of pools that may act as drought refugia; and instream habitat features including large woody habitat (snag) loading. • Calculate commence-to-inundate flow thresholds of select habitat features where feasible including benches, wetland entry/exit points, large woody habitat and root balls/bank overhangs. • Identify and map threats and processes that may influence the extent and condition of aquatic and riparian habitat features. • Make recommendations to protect and improve river health, threatened species habitat enhancement, weed control, and other habitat features.

The spatial dataset is provided in the form of a geodatabase containing point, line and polygon features of the mapped habitats. Some of the features contain embedded geotagged photos. Detailed explanation of the fields used in the attribute tables for the various feature classes are available in "Appendix G: Metadata for geodatabases" of the accompanying "Fish Habitat Mapping - Lower Mehi River" report.