Urban Firefighting Technology
The concept behind fire hydrants originated in the 1600s as fire plugs.[1] Firefighters would drill holes in wooden street mains to gain access to water, transferring it out via bucket brigades or a hose that would suction out the water.[2] The hole would then be plugged and marked for future reference. Modern fire hydrants move much of this process above ground, taking advantage of water pumps to move water. Temperate areas use “wet barrel” hydrants in which pressurized water is kept above ground at all times. Other areas that regularly reach freezing temperature use “dry barrel” hydrants which use valves to pump water above ground when needed.[3]
The pump allowing for fire hydrants as we know them is called a vertical centrifugal deep well pump. Popularized in the early twentieth century, these pumps use a rotating impeller to force water up to the surface.[4] The development and spread of these pumps significantly shaped infrastructure across all domains, including agriculture. For instance, the affordable and reliable access to water that they provided, enabled the conversion of many acres of ranch land to orchards.
Additionally, the pompier ladder — first introduced in St. Louis in the 1880s — has played a large role in urban firefighting.[5] It features the rung structure of a typical ladder with hooks and serrated teeth on one side, allowing the ladder to be hooked over window ledges and railings. These ladders allow firefighters to scale buildings quickly to reach elevated fires, as well as to lower themselves quickly by tying ropes around the hooks and sliding down — either to escape fire or save civilians.
Firefighting technology continues to develop, especially as our understanding of fire and our relationship with it evolves. Thermal imaging is being used to better visualize fires as they get put out — for instance, identifying hot spots that may reignite when the fire appears to be out, avoiding backdrafts wherein fire in an enclosed space appears to be starved of oxygen but will roar to life as soon as firefighters enter to fight it, and for seeing through smoke which can obscure vision of a fire. Drones are being developed to use these imaging techniques to visualize fires at a larger scale, not just in urban centers but also in the wildland urban interface.[6]
[1] Curt Wohleber, “The Fire Hydrant,” American Heritage 3, vol. 17 (Winter 2002)
[2] John Kelly, “Hydrant history: More on the fabulous world of fire hydrants,” The Washington Post, (March 2, 2013)
[3] Curt Wohleber, “The Fire Hydrant,” American Heritage 3, vol. 17 (Winter 2002)
[4] “Revolutionary Machine: How Pumps Shaped Modern California,” The Huntington, (June 12, 2019), https://huntington.org/videos-recorded-programs/revolutionary-machine
[5] “Gleanings From The Mails: St. Louis Pompier Firemen. Some Clever Feats In Climbing By Agile Fellows With Curious Ladders.” The New York Times, (September 18, 1882)
[6] “The Future of Firefighting,” BBC Click, (November 26, 2018), https://www.youtube.com/watch?v=GewYBa1CmS4