Surviving the Evacuation, Book 21: Our Home, Too

A murderer stalks the post-apocalyptic wilderness of the Pacific Northwest.
A year after the outbreak and nuclear war, the planet is teetering on the edge of environmental collapse. Across the entire Northern Hemisphere, very few survived. Fourteen thousand Europeans and Canadians found safety behind the great defensive walls erected across Nova Scotia. Attacked by piratical bandits based out of New York, they have no choice but to flee. While Bill Wright organises their evacuation, Kim and Sholto remain in the Pacific Northwest, searching for a new home for all those in the east. Kim thinks they have months to prepare until a plane full of pilgrims arrives from the south, bringing a murderer with them.
Where the evacuation of Britain was a bloodbath, the Southern Pacific fared better. Survivors thrive in fortified enclaves in Thailand, the Philippines, and Indonesia. Thousands of Canadians found a new home in Australia's Northern Territory, albeit living in hastily built shanty towns where water is scarce and crime is rife. Now they want to return home.
After an assassination attempt on the leadership on Vancouver Island, an investigation is launched, and the hunt begins. Whoever the killers are, their backers are still in Australia. Finding them falls to Commissioner Tess Qwong, whose hunt takes her from crocodile-filled rivers to the densely packed refugee camp the exiled Canadians call home.
Set among the radioactive desolation of British Columbia, the undead-filled ruins of Washington State, and the exiled Canadians' capital in Australia's Northern Territory, Bill and Kim's dreams of creating a new and better world are fading, while the prospect of war only grows stronger.