128-26 From natural floodplain to artificial riverscape: Reconciling mining, urbanization, and public perceptions

Abstract:

Gravel mining on floodplains to meet demands of urban development represents an aggressive driver of landscape change. Yet, few studies have traced the paths of transformation over decadal timescales from integrated perspectives. Using mixed methods, this contribution tells the story of the evolution of the South Platte River floodplain near Denver, Colorado, under population pressures. GIS documented land-use change from 1937 – 2020; remote sensing detected the transition of mining pits into water reservoirs. A corpus of 1,263 newspaper articles (1990-2024), from Denver Post and Rocky Mountain News, revealed changing themes of social discourses. Results showed how agriculture (56 percent in 1937 to 7 percent in 2020) gave way to increasing human land use, with water reservoirs in the study area dominant by 2016. Of 172 gravel pits examined, 40 percent became permanent reservoirs. Another 12 percent were reservoirs at one time. Social contestation of mining remained limited in newspapers and websites, which often portrayed the floodplain as hybrid infrastructure for water supply and recreation. The example of the South Platte floodplain illustrates how a different trajectory of landscape change is possible, beyond degradation wrought by human activity. It also daylights the gravel extraction underpinning the present landscape and the governance choices that elevated human uses over nonhuman habitats.

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