* 'More reasonable' estimate C$2.6-C$4.7 billion -BMO
* Bill would make it Canada's costliest natural disaster
TORONTO, May 5 (Reuters) - A wildfire in the Alberta city of
Fort McMurray could cost insurers as much as C$9 billion, making
it by far the costliest ever Canadian natural disaster,
according to research by Bank of Montreal Capital Markets.
BMO Capital Markets analyst Tom MacKinnon said that figure
was a worst-case scenario based on a comparison to a wildfire in
Slave Lake, Alberta in 2011. The bill for insurers was C$700
million in that fire, and the Fort McMurray fire is bigger and
the properties more valuable.
"Since Fort McMurray is nearly 10 times the size of Slave
Lake, a disaster of the same magnitude impacting nearly all of
Fort McMurray could potentially lead to C$9 billion in insured
industry losses," MacKinnon said in a research note.
MacKinnon said a "more reasonable estimate" might be for
total industry losses of between C$2.6 billion and C$4.7
billion, still by far the largest potential catastrophe loss in
Canadian history.
The Slave Lake fire was previously Canada's biggest
insurance loss from wildfire. The costliest natural disasters
were the C$1.9 billion in losses from the North American ice
storm of 1998 and the Alberta floods of 2013.
The Fort McMurray fire, now in its fifth day on Thursday,
has grown to five times its initial size and prompted the full
evacuation of the area's 88,000 residents.
The uncontrolled blaze has so far destroyed 1,600 buildings
compared with 374 in the Slave Lake Fire, with another 19,000
potentially under threat.
($1 = 1.2857 Canadian dollars)