5.1.7 Between a rock and a fiery place: Navigating an Urban Fire Storm

“Oh, a storm is threat’ning,
My very life today,
If I don’t get some shelter,
Oh yeah, I’m gonna fade away,” Jagger & Richards, 1969.

When fire breaks out within the mineral-based materiality of present-day London, as Wren, Hooke, and Evelyn anticipated, its spread is limited not merely by the application of water and/or other fire suppressing substances and actions, but by the relative absence of fuel [carbon-based materials]. But, change the materiality and, as in the wildland, one changes the urban fire regime. Consequently, the Great Fire and its several antecedents are indicative of the fire scenarios that may be anticipated within a future city that is built not of stone, cement, glass, and steel, but of biomass. For example, whereupon wooden tower blocks are built in abundance, we could expect to see the return of an urban fire season, the duration thereof coupled to the climate and more specifically to its meteorological manifestations. As discussed earlier, we need accommodate for not one, but a bandwidth of climatological scenarios. As relates to the city, should the direction of travel be towards a relatively arid future, therein similar such weather extremes as were witnessed in 17th Century London, we might anticipate that, as was the case three and a half centuries ago, fires would peak from spring through autumn. However, as in present-day California, whereupon periods absent of precipitation were extended, so too would be the urban fire season.

Adding yet further fuel to the fire, both recent real-world events, and theoretical and computer models speak to a future of chronic water shortages (Kummu et al, 2016), therein yet another correlation with the environmental circumstances that under- pinned the Great Fire. Given that regional per capita water consumption is higher today than in the 17th Century (Ibidem), and the population of London is more than hundred-fold that of 1666, even accommodating for our many times greater capacity to filtrate and, more broadly, to process water, we might reasonably expect that, whereupon London becomes subject to similar meteorological conditions as were manifest during the Little Ice Age, it is not beyond possibility that the city could nigh run dry. Recent analyses by Greater London Authority find “the city is pushing close to capacity and is likely to have supply problems by 2025 and “serious shortages” by 2040 (BBC News, 2018, online). Today, as in 1666, 80% of London’s mains water comes from rivers [Thames and Lea], and its annual precipitation is sizeably lower than cities including Paris and New York (Ibidem). Ironically, the phrase “it never rains, but pours” applies, for while water is scarcer in times of drought, demand increases proportionate to processes including perspiration, transpiration, and evaporation. Acknowledging the systemic nature of the problem, UNESCO’s latest Water Development Report calls for “Nature-based Solutions”, which recognise that water is not “an isolated element”, but “an integral part of a complex natural process” (UNESCO, 2018, p.1).

The medium to worst-case drought scenarios as could unfold remain hypothetical, thus we can but imagine how London would cope were the stones yet again ready to ‘burst into flames’. Bringing a global perspective to the issue, a recent study found “nearly all sub-national trajectories show an increasing trend in water scarcity” (Ibidem, online). Triangulating this trend with a possible migration to biomass-based urban materiality, be it in London, or elsewhere, whereupon water supplies were scant, fire suppression efforts would be greatly hindered. While fire suppressants are sometimes used to limit the spread of wildland fires, though their chemical constituents are not currently classified as harmful to humans and other mammals (Labat Environmental, 2013), some are irritants to skin and eyes, therein whereupon persons come into contact with these substances they need be removed through washing (Kalabokidis, 2000). Furthermore, chemicals used in fire retardants must not be consumed therein any vegetation contaminated therewith must be destroyed. Inhalation of the chemicals therein is to be avoided (Ibidem). More seriously still, a growing body of data suggests that fire retardants may have carcinogenic effects, the study thereof part of a wider interrogation to establish why U.S. firefighters have a higher rate of cancer-related mortality than the general populous (NIOSH, 2018). But, while the risks fire-retardants pose to members of the class Mammalia are yet to be fully quantified, recent studies make apparent the risks to aquatic life, this being a consequence of factors including the release of ammonia upon dissolving into waterways (Scauzillo, 2016; Hogue, 2011).

However, the risk posed by fire-retardants extends beyond the advent of a fire outbreak, for flame retardants as were once commonly used to prevent against fire in the home and the wider urban environment have been found to have sufficiently adverse health impacts as to necessitate their removal (Maron, 2013; Gross, 2013; Grossman, 2011; Gromicko, n.d.).

Whether in the wildland or in the urban past, we find clues as to how various emergent elements may combine to create a new urban fire regime. For example, whereupon, be it in consequence of demand outstripping supply of certain mineral- based materials, and/or attempts to reduce carbon emissions, and/or architectural researcher and practitioner interest in the creative potentialities of a biomaterialities, or otherwise, humanity migrates away from stone, cement, steel, and glass and towards wood and other carbon-based materials, abundant would be the potential fuel-source for a fire. While the state thereof would be seasonably variable, if, as myriad models suggest, the climatic outlook is one of extremes, we might reasonably assume that from spring to autumn the fuel state would be tinder-dry, with the timing thereof coinciding with periods of water scarcity. Thus, two of the three sides of an emerging urban fire triangle in place [oxygen and fuel], one might speculate as to the spatiotemporal distribution of the third. Might history repeat itself? The flash fiction as follows this section explores that possibility.

As discussed earlier, prior to the arrival of the genus Homo, the primary ignition source of fires was lightening. However, since the ‘theft of fire’ humans have been igniting landscapes with the aid of an ever-increasing arsenal of incendiaries. But, in anthropogenic climate change, our species may have inadvertently extended the impacts of our promethean acquisition, for so long as average global temperatures increase, models suggest that so too will electrical storms, therein the Lightning Activity Level. A study by University of California, Berkley estimates the sum thereof will increase 12 ± 5% for every 1°C of warming in the U.S., which can be applied as a proxy for levels as may be anticipated in London and other cities in the Global North (Romps et al, 2014). The thermal conductivity of wood “increases as density, moisture content, temperature, or extractive content of the wood increases”, with further influencing factors including grain angle and quantity of water-soluble salts, the orders of magnitude variable by ten (Glass and Zelinka, 2010, p.4-11). Of the above, that wood’s conductivity is coupled to temperature is particularly pertinent, and a marked distinction from metals, of which the conductivity rises not with temperature.

Further possible ignition sources are numerous, with examples including accident, such as when, in 1929, a fire broke out at the Empire State Building in consequence of a miscalculation on the part of a recently qualified pilot that took a biplane for a joyride (Tauranac, 1995), and terrorism, such as occurred at The Twin Towers on September 11th 2001. Indeed, the flammability of wood may attract higher than average acts of criminality towards skyscrapers built thereof. Bringing perspective thereto, in the aftermath of the Grenfell Tower fire, such is the extent of the perceived risk of arson and terrorism to tower blocks which, encased in cladding that has failed combustibility tests are yet to be refurbished with safer alternatives, that public officials have taken measures to help prevent against such attacks. Given that a “council-owned block in Slough, Berkshire, with combustible insulation has already been attacked by arsonists several times”, wise are they as pre-empt such actions (Booth, 2016, online).

While in temperate climatic times the matter may be all too easy to forget, whether in the wildland, at the interface therewith, or in the heart of a city, fire sits at the apex of several Earth systems. Therein, when the climate changes fire is an elemental canary in an urban ‘coalmine’: the difference between the molecular structure of wood and coal relatively incremental.

City of London, September 2nd 2066: a flash fiction

Trees turned into torches, as embers cast adrift by an East wind ignited the tinder-dry urban forest with the ferocity of the fire of four-hundred years earlier. The city’s fire hydrants fallen victim to the several-year long drought, citizens fled frantically by whatsoever means were at their disposal.

>Continue to Chapter 5.1.8 here.

The thesis is also available in PDF format, downloadable in several parts on Academia and Researchgate.

Note that figures have been removed from the digital version hosted on this site, but are included in the PDFs available at the links above.

Citation: Sterry, M. L., (2018) Panarchistic Architecture: Building Wildland-Urban Interface Resilience to Wildfire through Design Thinking, Practice and Building Codes Modelled on Ecological Systems Theory. PhD Thesis, Advanced Virtual and Technological Architecture Research [AVATAR] group, University of Greenwich, London.