USGS Reviews Streamflow Conditions In 2006
This past year has produced some record-breaking high streamflow conditions in the Northeast, as well as some near-record lows in other areas of the country, the U.S. Geological Survey (USGS) announced on Jan. 12. In a new USGS publication, "Streamflow of 2006 - Water Year Summary," changes in streamflow over the course of 2006 are examined relative to conditions over the past 75 years.
Some areas of the country experienced higher streamflow than usual. For example, parts of New England recorded their highest annual flows since 1930. At the same time, below normal conditions were prevalent in Texas and other states in the central and southern Great Plains, parts of the Southeast, and Alaska.
"Despite these regional highs and lows, however, streamflow conditions nationwide were relatively typical," said Harry Lins, hydrologist with the USGS surface water program. "We expect in any given year that one percent of streamgauges will experience a new all-time record high or all-time record low streamflow. In 2006, two percent of streamgauges reported new record high streamflow, most of which were in New England, and 1 percent of streamgauges experienced new record lows."
USGS plans to provide similar summaries every year. Robert Hirsch, associate director for water, said "These types of summaries are very important as they place annual streamflow in a historic context and help to provide insights on whether conditions reflect short-term (year to year or seasonal) hydrologic fluctuations or longer term, more global influences. They reinforce the critical need for a stable streamflow monitoring network over the long term."
This first-ever USGS summary of seasonal, regional and national streamflow conditions for water year 2006 can be accessed at http://water.usgs.gov/waterwatch/2006summary.
This article originally appeared in the 01/01/2007 issue of Environmental Protection.