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Flooding

Why Cover Flooding?

Floods kill people and destroy homes in many parts of the United States every year. Federal agencies estimate that an average of over 125 people die every year in the United States because of flooding, although losses vary widely from year to year. Property damage ranges into the billions each year, and has been rising in recent decades.

Of course the live video of a family clinging to their car in a swollen river as rescuers winch down from a helicopter is so compelling that few viewers can change channels. But flooding is also worth covering because if people are informed, they can make decisions which will save lives and reduce property loss.

Story Ideas

1. What are the main systems in your community for warning people in flood-prone areas of imminent danger? Are people aware of how and where to get flood warning information? Do they actually seek or receive the information? What plans and methods do local public safety officials have for warning people if evacuation is needed?

2. Have media in your area informed people how to prepare for flooding emergencies and how to respond to flood situations?

3. What areas in your community are most vulnerable to flooding? Under what circumstances?

4. What plans does your community have for dealing with flood emergencies at the time they are happening? Are evacuation plans clear and adequate?

5. Are there plans for keeping man-made hazards (chlorine and propane tanks, petroleum pipelines, etc.) from compounding the problem? Are government and private agency responsibilities clear?

6. What steps has your community taken to prevent or minimize death, injury, and damage from flooding?

7. Have structures been built recently in any of the flood-vulnerable areas in your community? What zoning, planning, and building regulations in your local jurisdictions govern whether or how people build in flood plains? Do they work?

8. Does your community belong to the National Flood Insurance Program?

9. What engineering approaches has your community taken to storm drainage?

Background and Context

As the deadliest and most damaging of U.S. weather hazards, floods have long been the focus of dreadful fascination by the public. Sometimes it is the scale that awes us -- as in the legendary Mississippi River flood of 1927. Sometimes it is the sudden lethality -- as in the 1889 Johnstown Flood that killed more than 2,209 people.

Flooding actually occurs from a range of causes and conditions -- not always the ones that first come to mind. For example, few people appreciate that inland flooding has been the cause of more than half the deaths arising from hurricanes in the last three decades. Of the 56 people who died in 1999’s Hurricane Floyd, 50 drowned from inland flooding. Torrential rains can accumulate when a storm becomes "stalled" in a certain location, even hundreds of miles from the coast.

Of course, river flooding is the kind we think of most commonly. Heavy rains or rapid snowmelt on upstream watersheds cause rivers to rise -- more so at chokepoints or where tributaries converge.

Coastal flooding is also very common. In many places, coastal land is very close to sea level, and therefore vulnerable. During hurricanes or other large storms, waves may be much higher than normal, and super-low atmospheric pressure often forces sea level to rise a dozen feet or more above normal in a "storm surge." When violent surf and storm surge coincide with normal high tides, the results can be catastrophic.

Less often thought of are the floods that can result from the failure of dams, impoundments, or other regulatory systems. The Johnstown flood is an example. There are more than 76,000 dams in the National Inventory of Dams, and probably others uncounted.

FEMA, which runs the National Dam Safety Program, says there are 10,400 high-hazard and 13,300 significant-hazard dams in the United States FEMA says "Emergency Action Plans" are essential for all of these dams, but that so far some 70 percent still do not have them. According to the National Performance of Dams Program at Stanford University, "1,595 significant hazard dams are within one mile of a downstream city." To keep things in perspective, it is worth remembering that many dams offer major protection to the public from flood control.

Floods can be a concern even in arid and semi-desert parts of the country, such as those in the West. Flash floods there are more of a danger because people do not expect them. Arroyos and washes, or normally dry streambeds and gullies, can fill with water within minutes or seconds during an intense downpour. Because roads often follow their contours, they may present danger to people in cars.

A flash flood is really any sudden, severe flood event, and they can have a variety of causes -- although large sudden downpours are the main ones. The effects of a downpour are worsened when terrain will not absorb water. Reasons vary: soil type (e.g. clay), lack of vegetation, steepness, extensive pavement (urban areas), frozen or ice-covered soil, or the saturation of soil by previous rains.

Another cause of flooding in some areas is ice jams. In colder northern areas, ice sheets form on the surface of a river during cold winter months of low flow. Warmer weather and higher flows cause the ice to break up into huge slabs that the current pushes downstream. When these slabs pile up against some obstacle, they form a dam that causes water to pool upstream -- and flooding results.

Floods typically get the most headlines when waters are about to crest. But there are important post-flood stories that need telling as well. Members of a flood-stricken community need all kinds of information to avoid pitfalls and deal with problems. For example, failure of normal sewage and drinking water systems means people need advice about how to find safe drinking water. They need to avoid pumping out flooded basements too quickly to prevent water pressure from destroying foundations. They need to understand and address the problems of mold and mildew in waterlogged buildings. And of course they need advice on how to connect with disaster- aid agencies.

Issues

The federal government spends several billion dollars on disaster aid in any given year -- a major share of it going to communities hit by flooding. Almost everybody agrees that people flooded out of their homes need immediate help.

But important issues arise over whether money is better spent preventing losses before-the-fact than compensating for them after-the-fact. And it is also an issue whether taxpayer money spent merely to compensate for flood loss does not encourage, even subsidize, people to remain in harm’s way.

Federal disaster aid funds temporary housing for people while damaged homes are being repaired, money to help repair homes, grants for basic living expenses, etc., when these are not covered by insurance. There are also low-interest loans to families, farms, and businesses to help them repair or replace lost property -- as well as unemployment aid, tax breaks, legal services, and crisis counseling. Another kind of aid goes to local governments, to help them clean up debris and restore facilities like roads, utilities, public buildings, and parks.

A different set of FEMA programs and funding are aimed at preventing and mitigating flood hazards. The most dramatic involves feds partly funding buyouts of flood-damaged property — to help people buy houses on dry land and the bought property reverting to uses like parks under ownership of local government. Other federal funds support measures like physically moving houses beyond the floodplain, elevating them on stilts, or floodproofing them.

The most important federal effort to address longer-term flood problems is the National Flood Insurance Program. People in flood-prone areas find it nearly impossible to get ordinary insurance against flooding -- precisely because they are in flood-prone areas. The NFIP involves a bargain from which both sides benefit. Local communities must qualify by adopting and enforcing floodplain management ordinances (which might, for example, forbid building new houses in floodplains). This reduces future flood damage and federal liability for disaster aid. In return, the federal government backs flood insurance offered in these communities by participating private insurance companies. National Flood Insurance is offered in more than 19,000 U.S. communities.

Flood issues spur many policy and political debates at both the local and national levels. Although the NFIP insists that the program pays for itself, critics often charge that it is federally subsidized.

The debate is likely to emerge again as Congress and the President struggle with the 2002 budget. The Clinton administration, following the great Mississippi-Missouri flood of 1993, shifted a much greater emphasis in funding toward mitigation and buyouts, to the applause of environmentalists. President Bush’s budget proposal would de-emphasize mitigation in favor of more direct (and politically popular) disaster aid.

Players and Sources

Federal Emergency Management Agency (FEMA). FEMA is involved in almost all facets of the flooding story. This independent federal agency administers flood disaster aid and also administers the National Flood Insurance Program. The "working end" of FEMA, especially during a disaster, is in its regional offices and local field offices.

- National Flood Insurance Program. Press contact: Mark Stevens, (202) 646-3969, mark.stevens@fema.gov, http://www.fema.gov/nfip/.

- National Dam Safety Program. This FEMA-based program is actually the nexus of several federal and state interagency dam-safety programs. FEMA convenes the National Dam Safety Review Board and Interagency Committee on Dam Safety. See http://www.fema.gov/mit/damsafe/.

- Map Service Center (flood plain maps): http://msc.fema.gov/MSC/.

National Oceanic and Atmospheric Administration. NOAA’s involvement with flood issues lies primarily in monitoring, understanding, and forecasting weather. NOAA also has lots of nifty aerial and satellite photos of flood conditions.

- National Weather Service. Press contact (general): John Leslie, (301) 713-0622. For Midwest flooding: Patrick Slattery, NWS Central Region, (816) 426-7621, ext. 621. NWS press page: http://www.nws.noaa.gov/pa/.

- NWS general and weather info page: http://www.nws.noaa.gov/. Hurricane Flooding: A Deadly Inland Danger (backgrounder): http://www.nws.noaa.gov/oh/hurricane/inland_flooding.html.

- NOAA Flooding Page: http://www.noaa.gov/floods.html. Includes link to NOAA’s Hydrologic Information Center, which monitors not only river/streamflow conditions, but other conditions like soil moisture, snow, and longer-term meteorological outlooks.

National Hurricane Center/Tropical Prediction Center. For hurricane-related flooding. Everything from real-time updates to forecasts and historical background: http://www.nhc.noaa.gov/.

U.S. Geological Survey. The USGS maintains the official national network of stream gages, which show streamflow conditions in most of the important rivers and streams in the United States. The agency also does a range of research relevant to flooding. Real-time Streamflow Data: http://water.usgs.gov/realtime.html. Flood Tracking Site for Red River Basin: http://nd.water.usgs.gov/rrflood.html

U.S. Army Corps of Engineers. The Corps builds, maintains, and operates dams throughout the United States which normally help control flooding. They are also a key player in dam safety.

Association of State Floodplain Managers. Larry A. Larson (director): (608) 274-0123, Larry@floods.org, http://www.floods.org/index.htm. Listing of state agencies: http://www.floods.org/states.htm. National Association of Flood and Stormwater Management Agencies. Director: Susan Gilson (director): (202) 218-4122, http://www.nafsma.org/.

Floodplain Management Association. Publishes the peer-reviewed Journal of Floodplain Management. Laura Hromadka (director): (714) 766-8112, admin@floodplain.org, http://floodplain.org/index.htm.

Association of State Dam Safety Officials. Lori Spragens (director): (606) 257-5170. Lspragens@aol.com, http://www.damsafety.org/.

American Red Cross. Press page: http://www.redcross.org/press/. Flood Readiness Booklet: http://www.redcross.org/services/disaster/keepsafe/readyflood.pdf.

Reprinted with permission. Published in Environment Writer newsletter June 2001, by the National Safety Council's Environmental Health Center.