USGS Surface Water Information
New & Noteworthy
Today's Water Conditions
View maps of current and historical conditionsStreamflow
Flood and high flow
Surface water quality
USGS in Your State
USGS Water Science Centers are located in each state.
Other Water Sites
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Methods & Modeling
The NSS Program is a computer program that replaces the National Flood Frequency Program (NFF) to provide simple methods of estimating flood-peak discharges and low flow frequency/duration discharges.
StreamStats is a Web-based Geographic Information System (GIS) that provides users with access to an assortment of analytical tools that are useful for water-resources planning and management, and for engineering design applications, such as the design of bridges.
SWSTAT contains a number of options for statistically analyzing time-series data.
The “streamgage statistics” retrieval tool provides a table of basic summary statistics for the selected streamgage, as computed from daily values, for the period of record.
Assorted hydrologic, hydraulic, and statistical analysis software applications.