USGS report - stream flows occuring earlier

[The Straight Story]

USGS Scientists Document Widespread Increases in Streamflow and Changes in the Timing of Snowmelt Over the Past 50 Years
Released: 5/5/2005

Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communication
119 National Center
Reston, VA 20192 A.B. Wade - [e-mail]
Phone: [phone]

Reston, VA – U.S. Geological Survey (USGS) scientists have identified nationwide trends toward increasing streamflow in many areas of the nation since 1940 based on data collected from long-term USGS streamgages. This conclusion and several more interesting trends in our nation’s streamflows can be found in four new fact sheets recently issued by the agency.

"Understanding streamflow trends is essential to effective management of the nation’s water supply and is critical to developing strategies that mitigate the potential negative impacts of floods and droughts," said USGS Associate Director for Water Robert Hirsch.

In the first study, USGS scientists identified a nationwide trend that streamflow has been increasing in the United States since at least 1940. Most of the increases were during low-and-moderate streamflows. This means that, during typically dry periods, more water is now available in the stream.

In the second study, scientists discovered that over the last 30 years, winter/spring streamflows occurred one to two weeks earlier than in previous decades in northern or mountainous areas of New England. Similarly, in the third study, scientists found that streamflows in most western rivers occur almost one to three weeks earlier now than they did in the middle of the 20 th century.

http://www.usgs.gov/newsroom/article.asp?ID=703