Reconnaissance Report on Geotechnical Damage Caused by Tropical Cyclone Jasper in December 2023

This paper is focussed on the Department of Transport and Main Roads (TMR) initial geotechnical response to damages caused by Tropical Cyclone Jasper (TC Jasper) to road infrastructure and batter slopes along the state-controlled road network in TMR’s Far North Queensland (FNQ) District of Queensland, Australia.

TC Jasper delivered extreme rainfalls over six days between 13 and 18 December 2023 in FNQ District. The highest accumulated total being 2,096mm in the area of Port Douglas and Mossman north of Cairns. Within areas of the TC Jasper path, rare to extremely rare rainfall occurrences resulted in severe flooding and geotechnical damage and closure of key state-controlled roads in FNQ. The roads closed included all four range crossings providing access to the Northern Tablelands. Communities were isolated, and tourism and regional transport severely impacted.

This paper provides a report on the geotechnical damage caused by TC Jasper to seven key state-controlled roads in TMR’s FNQ District, and outcomes from the event reconnaissance approach used by TMR’s Engineering and Technology Geotechnical Section in collaboration with TMR FNQ District office and RoadTek teams to re-open most of the closed roads and secure significantly damaged road sections within four days of the cyclone passing. Ongoing recovery efforts are progressively re-opening remaining roads.