The report analyses the geomorphology of the Mahurangi, Waikanae and Pelorus/Te Hoiere rivers to demonstrate how knowledge of their physical landforms and processes can support decision-making for river restoration. The rivers are all part of DOC’s Ngā Awa river restoration programme, which aims to improve biodiversity and habitat, and create more connected waterways.
The report begins with an introduction to geomorphology and how it relates to river restoration. A suite of desktop tools for analysing riverine geomorphology is then explained, which provides the background for case studies of the 3 Ngā Awa rivers and their catchments.
Each case study includes an analysis of the catchment, supported by informative maps and figures. The case studies explore of the structure of each river, how it is evolving and the drivers that are relevant for restoration. The individual catchment analyses are then compared across rivers.
A discussion of climate change and opportunities for enduring restoration follow, with concepts such as ‘working with the river’ and ‘allowing it room to move’ presented.
Tunnicliffe J, Brierley G, 2021. Geomorphological Evaluation of Three Ngā Awa Rivers: Desktop Analysis and Remote Assessment of River Connectivity and Dynamism. Prepared for Department of Conservation. 93 p.