Changing Flow and Channel Dynamics in a Rapidly Urbanizing River Basin

Keywords: Geomorphology, Fluvial Geomorphology, Urbanization, Urban River, Streamflow, Dams, Channel Morphology, Sustainability, Sediment Dynamics, Artificial Floodplain, Rivers
Abstract Type: Poster Abstract

Abstract

As urbanization continues to intensify in response to population pressures, understanding how urban rivers evolve in the presence of human activity becomes increasingly important. The South Platte River through Colorado is a prototype urban river flowing through a metropolitan area that has grown rapidly in recent decades. It provides an important source of water and ecosystem services for a large portion of the state, even while adjusting to a host of impacts imposed on the system. Despite its importance, few studies have investigated the ways in which the river has changed since the 1960s, when urbanization expanded and population increased several-fold in the Denver metropolitan area. This study examines the nature and extent of the transformation of the South Platte River into a partly natural and partly artificial feature on the landscape. We focus on three aspects of change: (1) a context and history of mining on floodplains; (2) streamflow and channel changes including the downstream impacts of dams; (3) sediment dynamics and the ways in which urban effects influence the rate of fining downstream. Findings from the South Platte River provide an important template for comparison with other examples of rapidly urbanizing rivers around the world. They also provide insights for managing such systems toward sustainability, and for living with them, into the future.