Land-Use Analysis and Simulated Effects of Land-Use Change and Aggregate Mining on Groundwater Flow in the South Platte River Valley, Brighton to Fort Lupton, Colorado

摘要

Land use in the South Platte River valley between the cities of Brighton and Fort Lupton, Colo., is undergoing change as urban areas expand, and the extent of aggregate mining in the Brighton-Fort Lupton area is increasing as the demand for aggregate grows in response to urban development. To improve understanding of land-use change and the potential effects of land-use change and aggregate mining on groundwater flow, the U.S. Geological Survey, in cooperation with the cities of Brighton and Fort Lupton, analyzed socioeconomic and land-use trends and constructed a numerical groundwater flow model of the South Platte alluvial aquifer in the Brighton-Fort Lupton area. The numerical groundwater flow model was used to simulate (1) steady-state hydrologic effects of predicted land-use conditions in 2020 and 2040, (2) transient cumulative hydrologic effects of the potential extent of reclaimed aggregate pits in 2020 and 2040, (3) transient hydrologic effects of actively dewatered aggregate pits, and (4) effects of different hypothetical pit spacings and configurations on groundwater levels. The SLEUTH (Slope, Land cover, Exclusion, Urbanization, Transportation, and Hillshade) urban-growth modeling program was used to predict the extent of urban area in 2020 and 2040.