Hydrospheric Sciences in America – A Bicentennial Review

Published by the American Geophysical Union as part of the Special Publications Series.

Water has been a principal agent in shaping our land through geologic time. During the past 200 years our people have used water in many ways to shape our country. In early times the rivers were the only highways through the wilderness, and thus they largely determined where centers of trade and cities grew. As hydropower at grist mills, water was the earliest source of mechanical power beyond hitching animal power. During much of our time we have overlooked the power of water as it eroded our landscape. We have used the river as a convenient receptor for our wastes. Water has made millions of arid acres productive through irrigation. During the most recent 50 years, particularly, we have increasingly attempted to control the damaging effects of water through programs of flood control. We have changed the hydrologic cycle largely in response to the needs of our urban areas for water supply, waste disposal, and drainage.