Water Resources of the United States


National Water Information System

View current and historical streamflow, ground-water level, and water-quality data

Today's Water Conditions

View comparisons of current and historical conditions using maps
Click map to go to current water resources conditions in the U.S.



USGS Water Science Centers are located in each state

USGS In Your State (clickable)There is a USGS Water Science Center office in each State.
Washington Oregon California Idaho Nevada Montana Wyoming Utah Colorado Arizona New Mexico North Dakota South Dakota Nebraska Kansas Oklahoma Texas Minnesota Iowa Missouri Arkansas Louisiana Wisconsin Illinois Mississippi Michigan Indiana Ohio Kentucky Tennessee Alabama Pennsylvania West Virginia Georgia Florida Caribbean Alaska Hawaii New York Vermont New Hampshire Maine Massachusettes South Carolina North Carolina Rhode Island Virginia Connecticut New Jersey Maryland-Delaware-D.C.

Cooperative Matching Funds

Products > Hazard Risk and Assessment > Floods

 Hazard and Risk Assessment Products by Subject

All Floods Products


thumbnail Ohio flood inundation maps –Maps are now available for Findlay, Killbuck, and Ottawa, Ohio. These maps show where flooding occurs at various high river levels.  They are just one example of USGS products and services developed in the 100 years since Ohio’s devastating Great Flood of 1913. (Press release) (Note: USGS WaterNow is available, allowing you to send an email or text message containing a USGS current-conditions streamgaging site number and quickly receive a reply with its most recent observation(s).


thumbnail Modeling Copper River Flows to Protect the Copper River Highway in Alaska –USGS, in cooperation with the Alaska Department of Transportation and Public Facilities, assessed and modeled hydrology and flow conditions along the Copper River Highway, which traverses the wide alluvial fan before the large, glacier-fed river enters the Gulf of Alaska. The highway is at risk because of its low grade, stream channel reconfiguration, and possible flooding by high flows of the Copper River. The USGS FaSTMECH model was used to simulate design highway changes and diversion channels to accommodate varying levels of flows. (Full report)


thumbnail Flood Inundation Maps for communities in New York –Digital flood-inundation maps for parts of the West Branch Delaware River through the Village and part of the Town of Delhi, New York were created by USGS, in cooperation with the Village of Delhi, the Delaware County Soil and Water Conservation District, and the Delaware County Planning Department. Delhi has experienced severe flooding along the West Branch Delaware River; most notably during January, 1996, June, 2006, and October, 2010, and August, 2011. Emergency responders benefit from a library of flood-inundation maps that are referenced to the stages recorded at the USGS streamgage upstream from Delhi. By referring to the appropriate map, emergency responders can discern the severity of flooding (depth of water and aerial extent), identify roads that are or will soon be flooded, and make plans for notification or evacuation of residents in harm's way based on current and near-future flood levels. (Read more)


thumbnail Flood Inundation Maps Available in Atlanta and other parts of Georgia –USGS, in cooperation with partners such as the City of Atlanta, estimate the areal extent and depth of flooding corresponding to selected water levels at USGS streamgages at Peachtree Creek at Atlanta, Georgia and at Chattahoochee River near Atlanta, Georgia. Access these and other maps at the Georgia Flood Inundation website.


thumbnail New Flood Warning System in Ottawa, Ohio –Digital flood-inundation maps of the Blanchard River in Ottawa, Ohio, were created by USGS in cooperation with the U.S. Department of Agriculture, Natural Resources Conservation Service, National Weather Service, and the Village of Ottawa, Ohio. The USGS developed interactive flood-inundation maps of the Blanchard River, and a flood-warning network that consists of three USGS streamgages that monitor streamflow and water levels, which will help emergency managers make informed decisions when flooding is imminent. The report and maps for the Ottawa Flood Warning Network and Flood-Inundation Mapping are available online. (Press release)


thumbnail Real-time Alerts for Flooding and Droughts across the Nation –Sign up for "Project Alerts" to keep up with USGS scientists as they respond to floods, droughts, and chemical spills. These "real time" notifications are official, and yet informal, and describe flood, drought, or water quality conditions across the country, as well as how USGS field crews are responding to the event. Stay up-to-date on flows in flooded streams, drought-depleted groundwater, water quality in a lake, stream, or well, and deployment of USGS storm surge sensors in anticipation of a hurricane. A link to the RSS feed and the web archive can be found at http://water.usgs.gov/alerts/. (Press release)


thumbnail Dam-breach and flood inundation assessments in Oklahoma –USGS, in cooperation with the City of Lawton, Oklahoma, released a report that simulates floods resulting from possible dam breaches and includes maps of downstream flood-inundation areas from Lakes Ellsworth and Lawtonka near Lawton, Oklahoma. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning the emergency response if a dam breach occurs. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas.


thumbnail New flood technology gets information out faster in Des Moines, Iowa –USGS, in cooperation with the City of Des Moines Department of Public Works, enhanced river monitoring equipment on streamgages to issue timely flood alerts (News story). New radio transmitters, placed on placed in key flooding areas on the Des Moines, Raccoon and North Rivers, and Four Mile and Walnut Creeks, provide information on river levels every 15 minutes, instead of every hour.


thumbnail Flood Inundation Map Libraries for communities in Indiana –USGS, in cooperation with the Indiana Office of Community and Rural Affairs, Indiana Department of Transportation, City of Fort Wayne, City of Indianapolis, Indiana Department of Homeland Security, Indianapolis Museum of Art, and the Indiana Department of Natural Resources Division of Water, is developing flood inundation map libraries at streamgages, collocated with National Weather Service flood forecast points across Indiana. Flood-inundation map libraries consist of maps that have been created in advance of a flood that are ready to be served through the Internet- each library consists of a set of flood extent and depth maps developed for predetermined stream stage intervals (for example, a map for each one foot of stage). A user can view real-time or forecast stage data from a USGS streamgage or National Weather Service (NWS) flood forecast point and quickly access the map corresponding to the stage data. As map libraries are completed, they will become available through an interactive Web viewer. This work is being undertaken as a collaborative project of the Indiana Silver Jackets Hazard Mitigation Task Force. The effort also is part of a larger Flood Inundation Mapping Program being undertaken by the USGS and partners.


thumbnail Flood inundation mapping science –A powerful new tool for flood response and mitigation are digital geospatial flood-inundation maps that show flood water extent and depth on the land surface. Because floods are the leading cause of natural-disaster losses, USGS is actively involved in the development of flood inundation mapping across the Nation pursuant to its major science strategy goal of reducing the vulnerability of the people and areas most at risk from natural hazards. Working with partners including the National Weather Service (NWS), U.S. Army Corps of Engineers (USACE), the Federal Emergency Management Agency (FEMA), state agencies, local agencies, and universities, the USGS is providing flood inundation mapping science resources to help build more resilient communities. (Just released: Flood inundation maps for the St. John and Fish Rivers in Fort Kent, Maine)


thumbnail Flood-frequency discharges in West Virginia –USGS, in cooperation with the West Virginia Department of Transportation, Division of Highways, determined flood-frequency discharges for 290 streamgage stations having a minimum of 9 years of record in West Virginia and surrounding states. Access to all surface-water monitoring gages (river, stream, lake, and rain) is available through the West Virginia Water Gaging Council--a statewide collaborative body to help achieve effective collection and dissemination of hydrological data applicable to the full range of water resources in West Virginia.


thumbnail Webcam and Real-Time Imagery Integrated with Traffic Safety Warning System for Urban Waterway in Columbia, South Carolina –A USGS webcam, installed and operated in cooperation with the City of Columbia, allows views of current river-stage conditions in Rocky Branch at Columbia, South Carolina. Rocky Branch has a small (<3 square miles) drainage area, with the majority of that drainage being impervious surfaces. Rainfall events in the Rocky Branch drainage basin often cause flash flood conditions. The USGS station monitors the elevation of Rocky Branch every 2.5 minutes and records the data every 15 minutes (available on the USGS NWISWeb). The station is also integrated with a traffic safety warning system. When the creek approaches flood stage, flashing lights warn motorists of potential water over the road. (The traffic safety warning system is maintained by the City of Columbia.)


thumbnail Remembrances of 1972 flood in South Dakota –USGS installs flood markers in Rapid City and Keystone, in remembrance of the 1972 flood that killed 238 people.


thumbnail Paleoflood science in the Black Hills of South Dakota –USGS in cooperation with the South Dakota Department, Federal Emergency Management Agency, City of Rapid City, and West Dakota Water Development District, released a report documenting paleofloods in the Black Hills area of South Dakota. The report shows that multiple floods during the last 2,000 years were substantially larger than the devastating Black Hills flood of 1972 that resulted in at least 238 deaths in the Rapid City and Keystone areas. Geologic evidence and carbon-14 dating were used to determine the ages, magnitudes, and frequencies of large floods that occurred along reaches of Spring, Rapid, Boxelder, and Elk Creeks in the last 1,000 to 2,000 years.


thumbnail Flooding in rural streams in Florida –USGS, in cooperation with the Florida Department of Transportation, presents methods for estimating the magnitude of floods for ungaged streams in Florida (streams that are not substantially affected by regulation, channelization, or urban development). (Full report)


thumbnail Flooding in urban and small rural streams in Georgia –USGS, in cooperation with the Georgia Department of Transportation, presents updated methods for estimating the magnitude and frequency of floods in ungaged urban and small basins in Georgia that are not substantially affected by regulation or tidal fluctuations. (Full report)


thumbnail Flooding in major rivers draining Iowa –USGS, in cooperation with the Iowa Department of Transportation and Iowa Highway Research Board, released several reports documenting the heavy flooding in 2008 in the Upper Iowa River in northeast Iowa and Iowa and Cedar River basins in eastern Iowa. (Report 1; Report 2)


thumbnail Flooding in the Black Hills, South Dakota –USGS, in cooperation with the South Dakota Department of Transportation and the National Weather Service, released a report documenting thunderstorms and flooding in August 2007 with a context provided by a history of other large storm and flood events in the Black Hills area of South Dakota near Hermosa and Piedmont, SD. The report also documents the history of other large storm and flood events in the Black Hills area.

USGS Home Water Climate Change Science Systems Ecosystems Energy, Minerals, & Env. Health Hazards USGS Intranet

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: https://water.usgs.gov/coop/products/hazards/flood.html
Page Contact Information: Water Webserver Team
Page Last Modified: Friday, 03-Jun-2016 13:44:52 EDT