About gravel in rural versus urban streams Urbanization of streams occurs when natural biota, soils, sediment and topography are altered through human activities such as deforestation and devegetation, and construction of buildings, roads, parking lots, etc.
Urbanization can change the hydrologic character of streams in many ways.
Increasing the peak discharge can have profound effects on sediment erosion, transport and deposition, changing the habitats and ecology of the stream. They also demonstrated that the urban streams were not extensively scoured or cleared of their coarse bed load, that urban streams still had plenty of bed gravels. Both streams show a similar shape to the distribution of gravel sizes. They found the same thing with almost all of the other streams analyzed. Pizzuto et al concluded that particles of this size are depleted from urban streams.