Floods

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Flooding is the most common and costliest natural hazard facing the United States. Over the last 30 years, floods have caused an average of $8 billion in damages and 82 deaths per year nationwide.

Basics

A flooded farm field. Image Copyright © Michael Collier. http://www.earthscienceworld.org/images

Flooding has many causes, including heavy rain, snow melting too fast, and dams or levees breaking. Coastal flooding occurs during hurricanes from heavy rainfall and storm surge, which causes sea level to rise temporarily at the shore.   Read more

Frequently Asked Questions

National Oceanic and Atmospheric Administration
U.S. Geological Survey
American Geosciences Institute

Latest News

Hawaiian flower
(2018-07-09)
June 28, 2018 Following the House passage of the Agriculture and Nutrition Act of 2018 (H.R. 2) by party line vote on June 21, the Senate amended H.R. 2 with text from S. 3042, the Agriculture Improvement Act of 2018, and an amendment providing a one-year extension of the National Flood Insurance...
Atlantic waves
(2018-05-04)
April 18, 2018 Following the historic 2017 hurricane season, members of Congress seem to be focusing more of their attention on updating and improving flood mapping efforts nationwide. Currently, the Federal Emergency Management Agency (FEMA) produces flood hazard maps for the nation, which can be...
Mammatus clouds that are usually associated with thunderstorms.
(2017-12-13)
November 14, 2017 Following months of debate on the floor continuing late in the day on November 14, the House of Representatives passed legislation that would reauthorize the National Flood Insurance Program (NFIP) for five more years, while making several operational changes. According to the...
NASA hurricane satellite image
(2017-09-14)
August 29, 2017 In anticipation of Hurricane Harvey making landfall on the Gulf Coast, the U.S. Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), and National Aeronautics and Space Administration (NASA) were preparing for the massive storm by monitoring its...
NASA hurricane satellite image
(2017-05-18)
April 18, 2017 The Weather Research and Forecasting Innovation Act (H.R.353) was signed into law by President Trump on April 18. This law prioritizes U.S. leadership in weather forecasting and research by authorizing new forecasting programs and support existing programs. The bill primarily focuses...
Flooding webinar postcard. Image Credit: AGI
(2017-02-07)
Join hundreds of attendees from around the world for an in-depth discussion on assessing, mitigating, and communicating flood risk tomorrow, Wednesday, February 8, 2017 at 1:00pm EST. Register here. More info below.   This webinar features experts from federal and state government, who will...
Screenshot of the Marine Cadastre National Viewer. Image Credit: NOAA, BOEM
(2016-09-30)
The American Meteorological Society (AMS) Policy Program’s workshop, “Opportunities and Needs in Integrated Water Prediction, Risk Assessment, and Management for Coastal Resilience,” concluded on September 28th, providing insights to coastal scientists and managers on how to better serve their...
Screenshot of the USGS Coastal Change Hazards Portal map
(2016-09-29)
On September 27th and 28th, our Critical Issues intern attended a workshop hosted by the American Meteorological Society (AMS) Policy Program: “Opportunities and Needs in Integrated Water Prediction, Risk Assessment, and Management for Coastal Resilience.” The first day focused on resilience issues...
Interactive map of Texas Gulf shoreline change rates. Image Credit: Bureau of Economic Geology, University of Texas
(2016-09-23)
#MapOfTheDay! Today the Critical Issues Program (@AGI_GeoIssues) shared an interactive map of shoreline change rates along the Texas Gulf Coast from the Bureau of Economic Geology at the University of Texas Jackson School of Geosciences (@txgeosciences), which you can find at http://bit.ly/1GoF214...
August 2016 Statewide Precipitation Ranks. Image Credit: NOAA
(2016-09-21)
The National Oceanic and Atmospheric Administration (NOAA) held their latest Monthly Climate Briefing on September 15, 2016, and we have summarized the highlights for you below: •  August 2016 is the 17th warmest (73.6°F, 1.5°F above average), 2nd wettest August (3.47", 0.85" above average) since...

Case Studies & Factsheets

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Introduction Dry wells improve stormwater drainage and aquifer recharge by providing a fast, direct route for rainwater to drain deep into underlying sediment and rock. Dry wells are most common in the western U.S. where clay or caliche layers slow down the natural drainage of water into...

CI_Factsheet_2017_4_drywellbasics_170906_thumb.JPG

What is a Dry Well? A dry well is a well that is used to transmit surface water underground and is deeper than its width at the surface (see image, below). Most dry wells are 30 to 70 feet deep and 3 feet wide at the surface. They are lined with perforated casings and can be filled with gravel...

Pre-Ike (left) and post-Ike (right) ASTER imagery of Galveston Island, the Bolívar Peninsula, and the mainland in August 2006. Healthy (red) and dead (brown) vegetation shows storm surge inundation effects. Image Credit: Jesse Allen, NASA Earth Observ.

Defining the Problem Hurricanes bring not only intense rainfall, but also high winds and flooding. This flooding is powered by the hurricane storm surge: a rise in coastal sea level caused by lowered barometric pressure and by wind blowing the ocean onto the land. The result is that waves and...

GOLI Online Courses

GOLI Course: Assessing, Mitigating, and Communicating Flood Risk. Image courtesy of Maria Coxx Lamm
Course Type: GOLI Online Course

Flooding is a perennial hazard for rivers and coasts alike. Every year, flooding results in billions of dollars of damage and the loss of dozens to hundreds of lives across the United States. Efforts to mitigate this hazard rely on the work of geoscientists, planners, and communicators to assess...

GOLI Course: Planning for Coastal Storm and Erosion Hazards; Image credit: USGS/USFWS - photo by Greg Thompson
Course Type: GOLI Online Course

Coastal hazards are a widespread challenge that cost millions (and sometimes billions) of dollars in the U.S. every year due to property loss and spending on mitigation measures. Based on the most recent U.S. Census, over 39% of the U.S. population lives in areas that may undergo significant...

Geological Surveys Database Publications

[20??], West Virginia Geological & Economic Survey
Fully revised, highly illustrated, user-friendly overview of West Virginia geology specific to the parks. 51/2" x 81/2" booklet with 2 maps on one double-sided 11" x 17" folded insert.
2018, Illinois State Geological Survey

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2018, Illinois State Geological Survey

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2018, Illinois State Geological Survey

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2018, United States Geological Survey

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2018, United States Geological Survey
Gas hydrate is a naturally occurring, ice-like substance that forms when water and gas combine under high pressure and at moderate temperatures. Methane is the most common gas present in gas hydrate, although other gases may also be included in hydrate structures, particularly in areas close to...
2018, United States Geological Survey
Flood-damage reduction in the United States has been a longstanding but elusive societal goal. The national strategy for reducing flood damage has shifted over recent decades from a focus on construction of flood-control dams and levee systems to a three-pronged strategy to (1) improve the design...
2018, United States Geological Survey
Many coastlines around the world have stair-step landforms, known as marine terraces. Marine terraces make up a large part of coastal California's landscape-from San Diego to Crescent City. Find out how these landscapes form, why marine terraces are of interest to scientists, and where you can...
2018, United States Geological Survey
The U.S. Geological Survey (USGS) maintains and operates more than 8,200 continuous streamgages nationwide. Types of data that may be collected, computed, and stored for streamgages include streamgage height (water-surface elevation), streamflow, and water quality. The streamflow data allow...
2018, United States Geological Survey
The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay (bay) as part of a multi-agency effort to address management, water supply, and ecological concerns. The San Francisco Bay area is home to millions of people, and the bay teems both...