On March 21, 1955, the Canadian government announced the construction of a Distant Early Warning (DEW) Line, a chain of radar stations stretching across the northern reaches of North America. This network was designed to provide advanced warning of potential Soviet air attacks during the height of the Cold War.
The DEW Line was the third and northernmost of three radar warning systems. Its predecessors—the Pinetree Line and the Mid-Canada Line—had been rapidly outpaced by technological advances by the mid-1950s and were deemed increasingly obsolete.
The DEW Line was a joint Canadian-American effort, with the United States funding construction while employing Canadian labour. Approximately 25,000 people worked on the project, which ultimately included 63 radar stations. The line spanned 5,000 kilometres, roughly along the 69th parallel, about 300 kilometres north of the Arctic Circle, stretching from Alaska to Baffin Island. Additional stations were located in the Faroe Islands, Greenland, and Iceland. Legislation authorizing construction had been signed by U.S. President Dwight D. Eisenhower on February 15, 1954.
Surveying and construction in the harsh Arctic environment posed immense challenges. Scottish-born surveyor John Anderson-Thompson mapped the station locations, and a staggering 460,000 tons of materials were transported by air, land, and sea to support the project. Construction was completed on July 31, 1957, marking a major milestone in North American defense.
The DEW Line became a cornerstone of North American Air Defence Command (NORAD) in 1958. Its stations were organized into three types:
- Gap Fillers: Small, unstaffed stations visited only by aircrews during the summer months.
- Intermediate stations: Staffed by a minimal crew—typically a chief, a mechanic, and a cook.
- Major stations: Fully staffed with more elaborate living quarters to support larger teams.
The radar systems included long-range AN/FPS-19 pulsar radars for detecting incoming aircraft, and AN/FPS-23 Doppler radars to monitor gaps between stations. Most stations were operated by the Royal Canadian Air Force (RCAF), with some staffed jointly with the U.S. Air Force.
However, the DEW Line’s effectiveness was eventually challenged by advances in Soviet military technology. The development of intercontinental ballistic missiles (ICBMs) as the primary delivery system for nuclear weapons meant that the line could no longer detect threats in time to allow for meaningful civil or military response. Despite this, many stations remained operational to monitor Soviet air activity and assert Canadian sovereignty in the Arctic.
In 1985, the DEW Line underwent a major upgrade, merging with newly built stations of the North Warning System. Between 1985 and 1994, 15 new FPS-117 phased-array radars were installed, modernizing the network. Following the collapse of the Soviet Union and the end of the Cold War, U.S. personnel withdrew from Canada in 1990, leaving operations to Canadian authorities. The Canadians continued to manage stations in Alaska and Greenland, maintaining the legacy of Arctic defense in the post-Cold War era.
johnmilner.ca 