The earthquake at the Pedder Impoundment is a warning – bigger quakes can and do happen here in Tasmania. The Greens share the concerns of Tasmanians about the magnitude 4 event and its implications on the Scotts Peak and Edgar Dams.
There has been long standing anxiety over the Edgar and Scotts Peak dams. They are rated as high risk due to their position on the Edgar Fault line, with Scotts Peak plagued by slumping and leakage since construction.
This is a serious situation – Hydro Tasmania should pause work on the Edgar Dam while an assessment of any non-viable structural compromises is undertaken. Hydro Tasmania must provide Parliament with a full report on today’s seismic activity, its implications for the dams, and the escalating costs of seismic safety upgrades.
Hydro Tasmania spent many years hiding the risk assessment and consequences of these dams failing in the event of an earthquake. Thanks to a Greens RTI, the community now knows the catastrophic consequences of a dam failure at both Scotts Peak and Edgar Dams.
Flood mapping revealed Huon Valley residents would have only hours to evacuate, with the loss of thousands of homes and potentially lives. The cost of strengthening Edgar Dam has already doubled from $15 million to more than $30 million, while Scotts Peak has blown out from $50 million to nearly $100 million.
With climate change driving more seismic events, and a magnitude 4 quake recorded today following a smaller one just weeks ago, the risks cannot be ignored. The only fool proof way to avoid disaster is to remove the dams entirely and restore Lake Pedder, delivering global value in the climate and biodiversity crisis.
