Ross River Spillway Gates
Attributable to Townsville Local Disaster Management Group Chair Mayor Jenny Hill:
“The first opening of the spillway gates occurred automatically when the dam level was 38.65m – as per the dam’s Emergency Action Plan (EAP) – which occurred about 1.30pm on 30 January,” Cr Hill said.
“The spillway gates opened to the next trigger point about an hour later. For the next 46 hours, the gates continued to operate automatically and increase in line with the EAP to manage increasing water inflows into the dam.
“Due to the extreme rainfall over the dam catchment – and the Bureau of Meteorology’s predictions of further intense rainfall – Townsville City Council decided to increase the spillway gates further than the EAP.
“The decision was not taken lightly and was done to reduce future downstream flooding and reduce the peak of the floodwaters. Prior to making the decision, Council sought expert advice from external agencies and technical consultants.
“The Townsville floods were much bigger than a 1 in 100 year event.
“A team of experts is currently analysing the data but it is clear that the flood levels in the Ross River were greater than a 1 in 500 year event.
“There were rainfall totals over parts of the Ross River Dam catchment during the past week that were in excess of 1 in 2000 year rainfall events.”