Floods in the United States are generally caused by excessive rainfall, excessive snowmelt, and dam failure. Below is a list of flood events that were of significant impact to the country during the 20th century, from 1900 through 1999, inclusive.
Decade of the 1900s
Kansas River – May 1903 The greatest flood of the Kansas River on record of in the memory of the oldest inhabitants living along the stream occurred May 23 to June 13, 1903.
Pacolet River (South Carolina) – June 1903 On June 6, 1903, after heavy rain, the Pacolet River destroyed or heavily damaged six large cotton mills, their associated dams, and 70 houses in the mill villages of Converse, Clifton, and Pacolet, South Carolina. Approximately 100 people were killed.
Heppner flood – June 1903
The third deadliest flash flood in US history, the normally placid Willow Creek burst its banks during an intense rain and hail storm. The city of Heppner, at the foothills of the Blue Mountains in eastern Oregon, was almost completely destroyed. 247 of Heppner's 1,400 residents died in the flood.Extreme Weather by Christopher C. Burt, Published 2004 by WW Norton & Co.
Sacramento River Flood – February 1904 From February 15 to the end of March 1904 occurred the most destructive flood as far as property was concerned in the recorded history of Sacramento. The greatest known flood occurred forty-odd years before, In January, 1862 and was due to rainfall, the precipitation in December, 1861 and January, 1862 just prior to it having been . This flood filled the entire flood plain, and was not limited, as was the later one, by the reclamation of large tracts of bottom land, nor was the channel below the mouth of the Feather River then filled with mining debris as it is now.
Susquehanna River – March 1904 Due mainly to ice gorges.
Mohawk River – March 1904 From March 25 to 31, 1904, there occurred a flood on Mohawk River, in New York State, which, while not the largest and most destructive in the recorded history of this stream, attained a maximum discharge on March 26 of 20.84 cubic feet per second per square mile.
Grand River – March 1904 Due mainly to the rapid melting of snow, flooding was more significant along the Grand, Saginaw, Kalamazoo, and River Raisin river basins than the St. Joseph and Huron River basins. In Lansing, it was the worst flood in the previous 135 years of its history. Many dams were either undermined or swept away. Kalamazoo saw two square miles of flooding during this event.U.S. Geological Survey. National Water Summary 1988–89 – Floods and Droughts: Michigan. Retrieved on May 5, 2007.
It was also considered the most destructive flood in Grand Rapids history. The Grand River went above bankfull on the night of March 24, rising slowly for the next four days. It broke the previous high-water mark by over , and was considered a once in 100 year flood. Over one-half of the population on the west side of the river was inundated. On the east bank of the river, numerous factories went underwater. There was one casualty. Damages totaled US$1.8 million (1904 dollars). To the left is an image showing the flooding in Battle Creek.Albreacht, A., Barnes, R., Culbert, J., Dakan, D., Gerardini, P., Hawkins, S., King, K., Mengel, R., O'Boyle, C., Packard, W., Ruel, R., Shelson, B., Vanderlaan, T., DeVries, S., and Dr. Steve R. Mattox. New Perspectives on the 1904 Flood in Grand Rapids, Michigan. Retrieved on May 5, 2007.
Wabash River – March 1904 Due mainly to rainfall.
Cache la Poudre River and Crow Creek – May 1904 In May, very heavy rains in northern Colorado and southern Wyoming caused a flood on the Cache la Poudre and Crow Creek which resulted in the loss of considerable property along them.
Belle Fourche and Red Rivers, Spearfish and Whitewood Creeks – June 1904 In the early part of June the Belle Fourche and other streams on the northern slope of the Black Hills were in destructive flood attaining on June 6 a gauge height of about 10.9 feet and a corresponding discharge of 5,931 second-feet. The absolute maximum gauge height during this flood was 11.25 feet and the corresponding discharge was 6,270 second-feet.
Arkansas, Kansas, Neosho, Verdigris and Osage Rivers in Southeastern Kansas – June and July 1904 In the latter part of June and the early part of July continued heavy rain caused the rivers in southeastern Kansas to be higher than ever known before and to cause much damage.
Robinson Run Flood – June 28, 1904
Scottdale Valley Flood – July 7, 1904 Dam Failure.
Johnstown Pennsylvania – July 8 and 9, 1904 Cloudburst
Troxton Canyon Arizona – July 30, 1904 Flash flood from Cloudburst, 30 feet high in canyon for 30 minutes.
Pinal Creek, Globe Arizona Flood – August 17, 1904
Las Animas, Purgatory, Arkansas Rivers Flood October 1904
Canadian, Cimarron and Mora River Flood – October 1904 From September 26 to 30 the precipitation over the greater portion of the drainage basin of the Canadian in New Mexico varied from 5 to 7 inches. This excess of monthly rainfall varied from 2.75 to about 6.5 inches in depth. The greatest precipitation in 24 consecutive hours was about 4 inches. Such a downpour of rain on a basin of steep nonabsorbent surface with little or no storage resulted in a sudden and very large, though local, flood.
The gauge at the gauging station at Logan was destroyed on October 2, 1904. Mr. W. G. Russell measured the cross section and slop of bed of the Canadian as short distance below the railway bridge at Logan on October 27, 1904, and found the cross section area to be about 13,500 square feet, the mean velocity 11.05 feet, the maximum discharge 149,396 cubic feet per second and the maximum stage above low water 31.3 feet.
Pecos River Flood – October 1904
La Plata River Flood – October 6, 1904 A storm caused the greatest flood along the middle and lower part of the La Plata velley since 1882. It reached its maximum stage at 4pm at Pendleton, passing over the floor of the highway bridge at a depth of 2 feet.
Sacramento Valley Flood – 1906
A tropical storm in late 1906 reported highest ever rainfalls in a southeast to northwest direction from Monterey to Ione in the Sierra Nevada foothills. An area of was flooded in the Sacramento Valley.
Pittsburgh, Pennsylvania flood – March 1907 Snowmelt combined with heavy rains by March 16 allowed the Allegheny, Monongahela, and Ohio rivers to swell out of their banks, leading to a flood of record in Pittsburgh. Damage to the city was estimated at US$5 million (1907 dollars). The death toll was low, with 6–12 perishing during the inundation.Library of Congress American Memory Project. Selected Panoramic Photographs. Retrieved on 2006-11-30.
Michigan flood – March 1908 In February, snowstorms had deposited a significant snowpack across the region. Then, in early March, heavy rains and warmer conditions set in, setting the stage for a flood. After the Homer Dam broke around 3 p.m. on March 7, the Kalamazoo River flooded Albion. By midnight, the bridges surrounding town were underwater. Six buildings in downtown Albion collapsed, which caused over US$125,000 in damage (1908 dollars).Willard Library. Photographs from Battle Creek History. Retrieved on May 6, 2007.Frank Passic. "The Great Flood of 1908". Retrieved on May 6, 2007.
California flood – 1909 The storm extended from Fort Ross on the coast to the Feather River basin. LaPorte, in the Feather River basin, had of rain in 20 days, an event with a return period of 12,000 years. The flood episodes of 1907 and 1909 in California resulted in an overhaul of planned statewide flood control designs.
Decade of the 1910s
Austin, Pennsylvania, dam failure – September 30, 1911 Heavy rains filling the Bayless reservoir cracked the concrete dam, sending an estimated 450,000,000 gallons downstream, and destroying most of the boroughs of Austin and Costello. A total of 78 people from Austin and 2 from Costello died during the inundation.
Great Flood – March 1913
Significant flooding occurred between March 23 and 26 after major rivers in the central and eastern United States flooded from runoff and several days of record-breaking rain. In Ohio nearly of rain during a series of three winter storms led to this flood event, which affected southwest, central, and eastern Ohio, especially cities and towns along the Great Miami River and Olentangy River valleys. It remains Ohio's "largest weather disaster" and Indiana's worst flood on record. Fires and tornadoes also wrought destruction. Storm-related flooding affected more than a dozen states: Alabama, Arkansas, Connecticut, Illinois, Indiana, Kentucky, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Vermont, and Virginia.
Dayton area
Dayton was totally devastated, being inundated for three days in late March 1913. The floods ended operations on the Ohio and Erie Canal, as they destroyed most of the locks and many miles of embankments. The death toll from this flood was 361, with total damages of US$100 million.
Columbus area On the Olentangy River, this flood broke the previous record for river stage by over . In the city of Delaware, 50–75 persons died after a break in the levee allowed a wall of water to sweep through downtown. Five of the city's bridges washed away.
The state capital, Columbus, suffered its worst ever flooding from the Olentangy and Scioto rivers. The Franklinton area on the west side was inundated after a levee broke on March 25. Four thousand houses were damaged or destroyed, between 90 and 100 lives were lost, and three of four Scioto River bridges downtown were destroyed (only the Rich Street bridge survived – Town, State and Broad street bridges were destroyed). The owner of The Columbus Dispatch, Robert F. Wolfe, chartered interurban trains to Buckeye Lake some east of Columbus to retrieve boats to rescue survivors. Flooding also occurred along Alum Creek on the city's east side.
Southern Ohio In Chillicothe, Scioto River flooding carved out a deep channel on Hickory Street. 18 lost their lives in the city.
The Ohio River reached a level of near Higginsport.
Texas flood – 1913 The Guadalupe and Trinity Rivers left their banks, and the Brazos River and the Colorado River joined to flood more than 3,000 square miles of land and cause the deaths of at least 177 people and massive property damage ($3,436,144 in the Brazos Valley alone). The flood caused the Brazos river to change course. It now entered the Gulf of Mexico at Freeport, Texas. Major flooding brought death and destruction of greater magnitude than previously experienced. The floods of 1913 and again in 1921 were the catalyst that would cause the state of Texas to attempt to tame the Brazos River.
Southern California floods - January 1916 During early 1916, heavy rains caused floods throughout Southern California, virtually cutting off San Diego County from the rest of the state for the greater part of a month. Due to the floods 28 people died and about ten million dollars in damages were caused, with the greatest losses occurring in San Diego County, where twenty-two people died mostly in Otay River valley when the Lower Otay Dam failed, releasing the contents of the Lower Otay Reservoir. Another estimate was that fifty lives were lost in San Diego County. Among the dead was an early Japanese American colony. San Diego residents blamed the floods on Charles Hatfield who was hired by the city of San Diego to create rain.
Southeast floods – July 1916
On July 5–6, 1916, a tropical cyclone swept across the Mississippi coast, which caused torrential rains across it and adjacent states; rains from this storm affected Southern states as far north as North Carolina and Tennessee.