As lingering spring rains soak eastern Iowa, crews from the U.S. Geological Survey continue efforts to make sure the streamgaging network is providing basic scientific information needed by water-resource managers and the community.
"The accurate flow data from the USGS is an essential part of NWS flood forecasts and warnings," said Jeff Zogg, NWS Senior Service Hydrologist. "Even small errors can negatively impact flood forecasts."
The National Weather Service uses USGS streamgaging information for flood forecasting. When flooding is frequent, the NWS stays in constant contact with the USGS. The USGS streamgaging network is the principal source of data used by the NWS to develop flood forecasts because of the stage and discharge information they provide.
The USGS operates 150 gages in Iowa that collect both stage and discharge information.
A reliable flood forecast, and subsequent warnings, requires a current source of stage, discharge, and precipitation data. NWS flood forecasts are based on river models that provide estimates of how a river will respond to rainfall. River stage and discharge data provided by USGS gaging stations are essential components of these river models and flood forecasts.
"The USGS places the utmost importance on the high quality and consistency of its streamgage network," said Kevin Richards, Director of the USGS Iowa Water Science Center. "Streamflow information is used in countless ways by government agencies, private industries, and the general public."
In addition to routine discharge measurements made at USGS streamgages, the USGS made 34 additional flood measurements once the rivers started rising in mid-April. With the forecasts calling for additional rain and snow over the next week, USGS scientists will be making extra measurements and checking equipment to assure the information is available for decision makers.
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