How did the U.S. Geological Survey study the effects of urban development?
Most previous studies of stream ecosystems have focused on either pristine areas or highly developed areas; little is known about how the gradual progression of urban development between these two extremes affects stream ecosystems. To address this, the USGS conducted a study from 2002 through 2003 through its NAWQA Program to determine the effects of urban development on the physical, chemical, and biological characteristics of stream ecosystems in the South Platte River Basin. The 28 study streams are located along the Front Range of the Rocky Mountains in the transition zone between the mountains and the plains. Study streams were chosen to represent (1) a wide range in the degree of urban development and (2) minimal natural variability due to factors such as geology, elevation, and climate, which can also affect stream ecosystems and therefore mask the effects of urban development. Stream locations that are strongly affected by wastewater-treatment-plant discharge were not included
