To be sure, Los Angeles was a fire-prone city long before roadways and urban development overtook the city’s wetlands. As Ryan Reft noted in a 2013 KCET article, sizeable areas throughout Los Angeles County experienced fires in 1930, 1935, 1943, 1956, 1961, 1966-67, 1970, 1978, 1982, 1985, 1993, 1996, and 2007.
Centuries before these fires, wildfire events were integral parts of Los Angeles’ ecology, to the extent that Indigenous Tongva people built their dwellings with moveable natural materials like thatch and fire-resistant mud, and adapted to the seasonal rhythms of the landscapes’ fire-prone woodlands, grasslands, and chaparral.
Yet beginning in the 1920’s and 1930’s, the construction of ambitious engineering projects across LA County, mainly designed to ease automobile transport by road, began to radically alter the city’s environment and climate. The construction of compressed, oiled dirt roadbeds and the subsequent installation of impervious, heat-absorbing asphalt surfaces incited the first transformative shifts. Then came more ambitious projects, after floods and landslides threatened the passability and integrity of the city’s newly-built roads.
In 1932, after a landslide collapsed a portion of one of the Pacific Palisades’ bluffs, endangering homes on the edge of the Palisades and making the Pacific Coast Highway (then called Roosevelt Highway) impassable, Los Angeles engineer Robert A. Hill devised an energy-intensive plan to stabilize the bluff’s slide-prone clay seam. It was one of the first of many twentieth-century schemes to control of Los Angeles’ turbulent terrain, attempts that culminated in failure.
Hill’s landslide control system consisted of a circuit of tunnels dug through the cliff connected to a gas-powered furnace. For about fifteen years after the system’s installation, the furnace and a constant supply of natural gas filled tunnels embedded in the Palisades bluff with a continuous stream of hot air. The hot air forced through the tunnels was meant to dry out the bluff’s clay seam.
Hill observed that the system worked well enough at the beginning. But in a matter of years, the bluff experienced additional landslides. All throughout the twentieth century, portions of the bluff still periodically broke off, leaving the highway beneath strewn with debris.
Engineers continued to manipulate Los Angeles’ soil and hydrology throughout the twentieth century with ambitious, if ineffective, land stabilization schemes like Hull’s. Flood control projects further limited the amount of water returning to Los Angeles’ terrestrial vegetation and subsoils. As with the attempted stabilization of the landslide-prone Palisades bluff, these engineering schemes were developed in direct response to perceived environmental threats—and in many cases, acute disasters.