U.S. Geological Survey hydrologic technicians are currently
taking measurements from hundreds of streams and rivers across the western
United States as part of a low flow study.
Spring snowpack in the western United States was extremely
low in 2015 compared to long-term averages.
Warmer winter temperatures meant that precipitation fell more often as
rain than snow and some places received less-than-normal precipitation.
In August and September, USGS hydrologic technicians will
measure stream flow and water temperature in hundreds of rivers and streams in
California, Idaho, Nevada, Oregon, Utah and Washington to document the severity
of this year’s drought.
“This year’s warmer, drier weather provides a preview of how
future droughts may impact water resources in the study area,” said Chris
Konrad, USGS hydrologist and study project chief. “The goal is to provide
information to resource managers to help understand differences in how streams
respond to drought and plan for future drought impacts throughout the region.”
With less spring and summer snowmelt at higher elevations,
many western rivers and streams reached their peak flows earlier than normal
and are now at or near historically low flows. These conditions create stresses
on domestic and agricultural water supplies, fish and wildlife, and forests and
“This is a large scale study including six states, nearly
500 streams and rivers, and dozens of technicians,” said Rich Ferrero, USGS
Northwest Regional Director. “The streamflow data will be important for future
drought planning and resource management decisions throughout the western
Hydrologic technicians from USGS water science centers are
measuring streamflow and USGS scientists will then compare those data with
measurements from previous years to answer several water-management questions,
-- Which rivers and streams depend on snowmelt and/or
groundwater to sustain flows?
-- How are low flows and associated higher stream
temperatures affecting habitat for fish and other aquatic species?
-- Does 2015 serve as a model for how streams will respond
to climate change?
-- Which rivers were most vulnerable to warm, dry weather in
terms of reaching historic low flow levels in 2015?
The data will be compiled and analyzed with a summary report
of findings planned for publication in late 2016.