Background: When fighting high-intensity wildfire, firefighters may construct a defensive fireline (fuel break) away from the raging front. The path of the fireline is the key to successful fire containment. However, the study of fireline path optimisation in the literature is limited.

Aims: We aim to find the optimal path for firefighting crews to encircle and contain a growing fire in the minimum time while keeping firefighters safe.

Methods: The model considers the realistic topographic factors that affect fire behaviour and fireline production rates. The forest landscape is partitioned into small homogeneous polygons according to their burning characteristics and modelled as a complex topological network using Delaunay triangulation. An algorithm is developed to find the fireline path for firefighting crews, traversing ‘safe’ edges of a dynamic network to meet at the earliest time at which the fireline path is completed.

Key results: Various experiments were conducted leading to insights on how the algorithm can be utilised to develop more effective firefighting strategies.

Conclusions: The proposed algorithm provides an efficient way to generate the optimal fireline path.

Implications: Future work could include the stochastic and dynamic factors in the system by considering probabilistic fire propagation and fireline construction rates.