Future management of the Waiho River

A case study: how to manage the powerful and dynamic Waiho River in South Westland. This webinar will focus on the work completed by the 2023 Waiho Technical Advisory Group (TAG), which was formed by the West Coast Regional Council in response to the ongoing aggradation of the riverbed, and the development of an avulsion path between the Waiho River and the Tatare Stream in February this year. The TAG was tasked with producing a 10-year management plan for the river. Utilising the extensive geomorphic understanding of the river system, a risk assessment of each stopbank in the protection network, and the PARA framework, the TAG developed a five phase plan involving a managed retreat from the Waiho’s true left floodplain. This rather drastic action will allow the Waiho River to access it’s entire fan surface (as opposed to just one third), giving it more space to distribute its incredibly high sediment load across, which slow the rate of vertical aggradation, and therefore reduce the pressure on the developing avulsion, as well as the true right stopbanks which protect the Franz Josef township. Register in advance for this webinar: https://zoom.us/webinar/register/WN_4m8YWviWQ_OxhAKrJN3lIA