Changes in the morphology of drainage channels of the hydrographic basin of Cadena stream, Santa Maria / RS

Abstract

This work presents different aspects of human interventions on natural systems in urban areas of Santa Maria city. Urban use and interest in the land has historically included significant drainage modifications. The urbanization has affected major floods, erosion and sedimentation in stream channels of the Cadena basin. In Santa Maria the channelization was a practice used to control flooding and drain wetlands. However there weren’t buildings to control bank stream erosion. Channelization involves widening, deepening or straightening of a channel which may be associated with considerable bank erosion which locally enlarges the width of a channel and it affects urban areas causing hazards. Moreover, the erosion increment may work its way up the tributaries as a series of knick points in response to urban’s stream changes. The analyses of the antropic intervention on the tributaries of Cadena stream divided the basins into low, medium and high intervention levels.

Keywords

• Urbanização
• bacia hidrográfica
• mudanças ambientais
• Urbanization
• hidrographic basin
• environmental changes