Floods : The Awesome Power

1. Floods : The Awesome Power Suzanne Van Cooten, Ph.D – NOAA/OAR National Severe Storms Laboratory

2. How Is A Flood Defined? Webster’s Dictionary Etymology: Middle English, from Old English flOd; akin to Old High German fluot flood, Old English flOwan to flow 1 a: A rising and overflowing of a body of water especially onto normally dry land; also: a condition of overflowing <rivers in flood> bcapitalized: a flood described in the Bible as covering the earth in the time of Noah2: The flowing in of the tide3: An overwhelming quantity or volume; also: a state of abundant flow or volume <a debate in full flood> NATIONAL WEATHER SERVICE MANUAL 10-950, SEPTEMBER 26, 2002 Operations and Services Hydrologic Services Program, NWSPD 10-9 Any high flow, overflow, or inundation by water which causes or threatens damage. How Is A Flash Flood Defined? Webster’s Dictionary A local flood of great volume and short duration generally resulting from heavy rainfall in the immediate vicinity NATIONAL WEATHER SERVICE MANUAL 10-950, SEPTEMBER 26, 2002 Operations and Services Hydrologic Services Program, NWSPD 10-9 A flood which occurs within six hours or less of the causative event. In some parts of the Nation, the actual time threshold for an event to be considered a flash flood may be less than six hours. How Can I Decide if it is a Flood or a Flash Flood? Duration of Time from Precipitation Event(s) to onset of flooding Common Flash Flood Producers- Heavy Localized Rainfall, Dam or Levee Failure, Sudden Release of Water held by an Ice Jam or Debris Flow Common Flood Producers- Regional Excessive Rainfall, Mainstem Seasonal River System Flooding

3. Floods- An International Perspective

5. International Events Windstorms (Includes Tornadoes and Hurricanes) 50 Percent of 650 Registered Events 96 Percent of Insured Loss for 2004 “Fab Four” consisting of Charley, Frances, Ivan, and Jeanne were the “costliest combination of storms in history.” Economic Losses of 60 Billion with 30 Billion carried by Insurance Industry Jeanne was responsible for record rainfall in Haiti and Dominican Republic where 2,000 people were killed in floods and torrents of mud Ivan was responsible for 11 billion in insured losses Japan was hit by a record 10 tropical cyclones from June-October Typhoons Chaba, Songda, and Tokage produced damage in excess of 14 billion with 7 billion dollars carried by the insurance industry November- Tropical Storm Winnie produced torrential rains over the Phillipines with 750 people killed in flood waters and landslides

6. Floods and Flash Floods One Quarter of all Natural Events (150) January- February- Brazil Experienced its worst flood catastrophe in 15 years with 160 people dead May- Haiti and Dominican Republic 2000 people died due to flood waters and mudslides June –August Monsoon Floods in Bangladesh, India, and Nepal Bangladesh 2/3 of the country was under water for most of the time 2200 people drowned and 5 billion in economic loss June-September China River Floods Hundreds of thousands of buildings destroyed 1,000 people drowned and economic losses of 8 billion dollars

7. 2004 Fatality Summary - 82 Flood , 34 Tornado, 34 Hurricane, 31 Lightning, 27 Cold, 28 Winter, 6 Heat

8. United States Flood Fatalities and Economic Impacts

9. 30 Year Average (1975-2004) Flood = 107, Lightning = 64, Tornado = 54, Hurricane = 15 10 Year Average (1995-2004) Flood = 88, Lightning = 49, Tornado = 57, Hurricane = 21 Flood Fatality Information from NWS Hydrologic Information Center Other Hazard Fatality Information from NWS Summary of Natural Hazard Statistics

10. With Caveats on Flood Data Economic Tabulations as outlined in Pielke, Jr., R.A., M.W. Downton, and J.Z. Barnard Miller, 2002: Flood Damage in the United States, 1926-2000: A Reanalysis of National Weather Service Estimates. Boulder, CO: UCAR.

11. National Flood Insurance Program – FEMA Web Page

12. Types of Flash Floods/Floods Flash Floods Intense “Quick-Burst” Rainfall Ice Jam/Debris Flows Dam Failures Landfalling Tropical Systems Floods (Prolonged Regional River System Flooding) Rainfall – Intensity, Duration, Frequency (Antecedent Conditions) Time of Day and Season (Outdoor Activities)

13. Flash Flood Significant Events June 14, 1990 – Shadyside, Ohio (Evening) 3-5 Inches Of Rain In Less Than 2 Hours Fell On Saturated Soils Most Deadly and Destructive Flash Flood since 1980 15-20 Foot Wall of Water 26 People Killed- 2 Bodies Recovered 30 Miles Downstream At he Hannibal Locks and Dam on the Ohio River 80 Homes Destroyed, 250 Damaged with 6-8 Million Dollars in Damage July 31, 1976 – Big Thompson Canyon Flood, Colorado (Evening) 8 Inches of Rainfall in One Hour 139 People with 30 Million Dollars of Damage

14. Ice Jams (From US Corps of Engineers Data and Web Pages) The rates of water level rise can vary from feet per minute to feet per hour during ice jam flooding. In some instances, communities have many hours of lead time between the time an ice jam forms and the start of flooding. In other cases, the lead time is a little as one hour. For example, in March 1992, an ice jam developed at 7:00 a.m. in Montpelier, VT. By 8:00 a.m. the downtown area was flooded (Figure 2-3). During the next 11 hours, the business district was covered with an average of 1.2 to 1.5 m (4 to 5 ft) of water. The event occurred so quickly that there was not sufficient time to warn residents so they could protect their goods. Even after water levels dropped, damage related to the flooding continued as cold temperatures caused freezeup of wet objects. Damages of less than one day were estimated at $5 million (FEMA 1992b). Ice Jam DatabaseUS Army, ERDC, CRREL-Ice Engineering Group72 Lyme RoadHanover, NH 03755 Phone: 603-646-4187Fax: 603-646-4477E-mail: kwhite@crrel.usace.army.mil Israel River, Lancaster, NH

16. Dam Breaks June 1, 1889 Johnstown, Pennsylvania 20 Million Tons of Water Released Official City Records list 2,207 dead but witnesses claim more March 12, 1928 – St Francisquito Canyon, California William Mulholland's great St. Francis Dam broke at three minutes before midnight on March 12, 1928, sending a 180-foot-high wall of water crashing down San Francisquito Canyon and claiming approximately 470 lives by the time the floodwaters reached the Pacific Ocean at Ventura. The piano keyboard in the foreground of this photograph is an eerie reminder of the families that were caught unawares in the middle of that fateful night. The flood was the second-worst disaster in California history, second only to the San Francisco earthquake and fire of 1906 Its waters swept through the Santa Clara Valley toward the Pacific Ocean, about 54 miles away. 65 miles of valley was devastated before the water finally made its way into the ocean between Oxnard and Ventura. At its peak the wall of water was said to be 78 feet high; by the time it hit Santa Paula, 42 miles south of the dam, the water was estimated to be 25 feet deep. Almost everything in its path was destroyed: livestock, structures, railways, bridges, livestock, and orchards. By the time it was over, parts of Ventura County lay under 70 feet of mud and debris. Over 500 people were killed and damage estimates topped $20 million. ((www.USC.EDU) www.scvhistory.com

17. November 1977 at 1:30 AM- Kelly Barnes Dam (Rock Crib) Toccoa, Georgia Dam Failure 40 People Died (Almost 50 percent Children) In 1899 Original dam constructed of interlocking sections of timber or concrete, forming cells which are filled with earth or broken rock.

19. Rappaport, E. Loss of Life In The United States Associated With Recent Atlantic Tropical Cyclones. Bulletin of the American Meteorological Society. Vol 81, No. 9, September 2000.

21. October-November 1998 Heavy Rains (Texas) Severe Flooding from 2 Heavy Rain Events 31 Deaths (NCDC Storm Data) CDC Web Page 29 Deaths with 22 from vehicles driven into high water Approximately 1.0 (1.1 adj 2002) Billion In Damage Number of Paid FEMA Losses: 4,678 Total FEMA Claims Paid: 76,257,393 (16,301 per claim)

22. http://floodsafety.com/media/pdfs/texas/October98.pdf

23. Northern Plains Flooding –April/May 1997 NCDC Storm Data – Approximately 3.7 (4.1 adjusted to 2002) Billion in damage/costs NCDC Storm Data – 11 deaths FEMA NFIP Number of Paid Losses =7,272 FEMA NFIP Total Losses Paid = 158,401,726 Dollars ($21,782 per claim) The important factors that set the stage for potential significant flooding of the Red River and its tributaries during April 1997 included greatly enhanced snowfall during the winter and a substantial buildup of river ice throughout the northern half of the Red River. These conditions resulted from a series of major cold-air outbreaks and winter storms from September 1996 to April 1997. During this period more than 200% of normal snowfall was observed over most of North Dakota, western Minnesota and northeastern South Dakota, with 125%-200% of normal snow covering the remainder of the upper Midwest, the northern Plains, Montana and most of Wyoming This highly unfavorable March-April 1997 thaw in the Red River Basin can be put into perspective by comparing it with the very favorable or "ideal" thaw of 1994, a year in which there was only minor flooding despite record or near-record snow fall at many locations during October 1993-February 1994. The 1994 thaw featured four periods of substantial basin-wide warming during March, along with significant refreezing at night. These conditions produced a much more uniform melt of snow and river ice throughout the basin, and resulted in a substantial reduction of the winter snowpack prior to the onset of the major April warming. The floods were then directly initiated by a highly abnormal thaw of this snowpack and river ice.

25. Floods – Not Only Nature’s Instruments of Change Past Policy Decisions and How These Decisions Will Be Viewed As We Tckle Water Management Issues and Impacts in the 21st Century

26. Floods As Policy Drivers FLOODS ON THE LOWER MISSISSIPPI: AN HISTORICAL ECONOMIC OVERVIEW Southern Region Technical Attachment 98-9 Trotter, P. , G. Alan Johnson, Robert Ricks, David R. Smith NWSFO, New Orleans/Baton Rouge, Louisiana Donnel Woods, WSO/COE, Vicksburg, Mississippi The 1927 flood left a disastrous impact upon the entire 1,250,000 mile2 river drainage. The unprecedented rainfall began over the whole basin in late summer 1926, and didn't abate until the summer of 1927. The flooding began at Memphis in the fall of 1926 and it was late August of 1927 before the last of the flood waters flowed into the Gulf below New Orleans. The levee system was decimated with over 120 crevasses (Fig. 1) and 165 million acres were inundated. There were 246 fatalities and over 600 thousand people were made homeless. The total damage was estimated at $230 million. John M. Barry in his book Rising Tide has eloquently outlined the social and economic impact of that natural disaster upon the nation. As Barry points out, a major portion of the 600 thousand people made homeless was black tenant farmers which made up the labor force of the agriculture-based Delta. Those refugees were not allowed to leave and were forced to work and live on the levees that year to provide damage control. Up to that time, flood relief and river management was largely driven by economics rather than humane concern for the citizens. Relations between diverse racial and economic groups were needlessly strained by the lack of planning and flood management procedures. Fearing that a flood in New Orleans would ruin the economic structure and investment stature of that city, bankers and commodities brokers convinced the governor to open the levee at Caernarvon 14 miles downstream. The destruction of the levee and the resulting flood inundated the two lower parishes of Louisiana displacing thousands of people and destroying the trapping, farming, and fishing industries for the following several years. Given the crevasses upstream from New Orleans, the necessity of dynamiting the levee was questionable. As a result of the devastation, the Flood Control Act of 1928 was passed. Levee and reservoir maintenance and management was placed in the hands of the Army Corps of Engineers (COE), with cooperation among levee boards, river commissions and emergency management officials. Rising Tide: The Great Mississippi Flood of 1927 and How It Changed America John M. Barry

28. NOAA Historical Photo Collection

30. FEMA/NOAA Aerial Photos

31. How Do I Get The Information?

32. Outlooks Watches

33. Statements Advisories/Warnings

34. Discussions

35. Fatality Trends and Multi-Agency Education Programs

37. Nearly half of all flash flood fatalities are automobile related.Water weighs 62.4 lbs. per cubic foot and typically flows downstream at 6 to 12 mph.When a vehicle stalls in water, the water's momentum is transferred to the car. For each foot water rises, 500 lbs. of lateral force are applied to the car.But the biggest factor is buoyancy. For each foot that water rises up the side of the car, the car displaces 1500 lbs. of water. In effect, the car weighs 1500 lbs. less for each foot water rises.Two feet of water will carry away most automobiles.

38. http://www.nws.noaa.gov/om/water/tadd/

39. Questions? Suzanne Van Cooten, Ph.D Research Hydrometeorologist NOAA/Office of Oceanic and Atmospheric Research National Severe Storms Laboratory 1313 Halley Avenue Norman, OK 73026 Office Phone (405) 366-0536 E-Mail: Suzanne.Van.Cooten@noaa.gov