'Alarming, serious situation': urgent action needed for rising Waiho River bed - Thu 29 Oct

The Waiho River near Franz Josef is experiencing alarming changes, with its riverbed rising by 20 centimeters annually and currently sitting two meters above the surrounding land. This situation poses a significant risk to the local population, prompting a technical advisory group to call for immediate action. Proposed measures could involve sacrificing farmland, relocating State Highway 6, and investing up to 100 million dollars to mitigate potential disasters.

Ian Fuller, a geomorphologist from Massey University, explains that the river's dynamics are driven by sediment deposition from the catchment area, particularly influenced by the Franz Josef Glacier. The ongoing accumulation of gravel and coarse materials is raising the riverbed, leading to concerns about the effectiveness of existing flood protection infrastructure. While recent upgrades have reduced the likelihood of stock bank failure, the consequences of such a failure could be catastrophic, especially if storm events cause rapid changes in the river's flow.

Fuller emphasizes the unpredictability of the river's behavior and the increasing danger posed to the community. He warns that without significant intervention, the risk to life will continue to grow, as the riverbed's elevation increases and the infrastructure struggles to cope with the changing conditions.

Massey University's Professor Ian Fuller says there is 'risk to life' with the rising Waiho River bed and we can't just keep raising the stop banks. See omnystudio.com/listener for privacy information.