U.S. Floods of 1977

By C.A. Perry, B.N. Aldridge, and H.C. Ross of the USGS

Significant flooding did not occur in 1977 until early April when eastern parts of the Ohio River Basin were inundated by a storm producing excessive amounts of rain. The headwaters of the Kanawha, Guyandotte, Big Sandy, Kentucky, Cumberland, and Tennessee Rivers located in southern West Virginia, southeastern Kentucky, extreme western Virginia, and northeastern Tennessee were most affected by the storm.

Rainfall amounts of between 4 and 15.5 in. fell over the western slopes of the Appalachian Mountains. The maximum rainfall occurred in southwestern West Virginia, over a period of about 30 hours. The 15.5 in. of rainfall was considerably more than the 5.5 in. expected for the 24-hour, 100-year recurrence-interval storm.

Record flooding was recorded on the Guyandotte River at Baileysville, West Virginia, and all along the Tug Fork River. Flood discharges at some locations were greater than the 100-year recurrence interval. Many small streams in the headwaters of the Tennessee River recorded new maximum discharges of record. No large cities were affected by the flooding, but a number of small towns and populated rural areas were severely damaged; 15 counties in Kentucky, 6 in Tennessee, 17 in Virginia, and 11 in West Virginia were declared Federal disaster areas. There were 22 deaths, and total damages were estimated at $430 million. About 40,000 families were affected in the four-State area.

A storm moved into the Mississippi Delta area of Louisiana during the evening of April 19 and produced rain in the area until the morning of April 22. Rainfall amounts from 6 to 13 in. were reported in the Delta area, and 15 in. of rain was reported west of the Delta. Record maximum discharges were recorded on the Tangipahoa, Tickfaw, Amite, and Comite Rivers.

The Johnstown, Pennsylvania, area experienced flash flooding as a result of almost continuous rains from about 7:00 p.m., July 19 to 4:00 a.m., July 20. Rainfall intensities during much of this time averaged 2 in/hr, with maximum rainfall totals of 12 in. recorded northeast of Johnstown. Flooding was severe along the east side of the Allegheny River Basin. Johnstown, located where the Stonycreek and Little Conemaugh Rivers join to form the Conemaugh River, was adversely affected by the flood. Water 4 to 8 ft deep flowed through the downtown streets. Seven earth-fill, gravity-type dams failed in the area. The worst dam failure, located on Laurel Run, caused 44 deaths. Maximum discharges of record were recorded at 11 streamflow-gaging stations in the area. Of these 11 stations, 6 recorded discharges with recurrence intervals of 100 years or greater. Overall, the catastrophic floods were responsible for 78 deaths, destroying 413 dwellings and causing major damage to 1,363 homes. Eight counties were declared Federal disaster areas, and an estimated $300 million in damages occurred.

The flood of August 27-28 in West Cache and Blue Beaver Creeks in southwestern Oklahoma was the result of a severe summer thunderstorm. Rainfall data indicated 24-hour totals of 12 in. immediately south of Cache, with an area-weighted average rainfall of 7.7 in. during a 6-hour storm period within a 200-mi² area. Damages were $1 million.

On September 12 and 13, two intense storms hit the Kansas City, Kansas and Missouri area within 12 hours of each other and caused severe flooding, especially on Brush Creek which runs through the metropolitan area. The storms both had recurrence intervals of 100 years and produced 6 to 7 in. of rain each. Total rainfall was as much as 16 in. in some areas of Kansas City. Twenty-five deaths were caused by the floods, and damages were more than $80 million.

The Eastern and Southeastern States were plagued by flood-producing rains during the months of October and November. Most of the flooding occurred on the west side of the Appalachian Mountains. Floods were especially severe in the headwaters of the Kanawha and Tennessee Rivers in eastern Tennessee, western Virginia, and North Carolina. The Holston River Basin in western Virginia and eastern Tennessee received excessive rainfall on October 2-3 and again on November 6-7, and several maximum discharges of record occurred on streams in the basin. The November 6-7 floods were especially severe along the New River in Tennessee. As much as 14 in. of total rainfall occurred in parts of North Carolina, creating floods that were said to be the among the worst in history in North Carolina. Recurrence intervals greater than 100 years were reported for four streamflow-gaging stations in North Carolina. The floods were responsible for 13 deaths, 3,600 homeless, and 9,000 unemployed. The floods destroyed 384 homes and 91 bridges, and caused 12 dams to fail. Fifty million dollars in damages were reported for North Carolina alone. Sixteen counties in North Carolina, eight in Virginia, and six in Tennessee were declared Federal disaster areas.

Rainfall of 5 to 7 in. caused severe flooding on small streams in northern Georgia on November 2-6 and eventually caused the failure of the Kelly Barnes Dam in Toccoa, Georgia. The dam failed at 1:30 a.m. on November 6, resulting in a 25-ft wave of water rushing down the narrow canyon toward the Toccoa Falls Bible College. The campus was inundated within minutes. One dormitory had 8 ft of water on the ground floor. A trailer park associated with the college was destroyed as 10 ft of water rushed through it. Thirty-nine deaths and $2.8 million in damages occurred during this flash flood.

A drought that had plagued the Pacific Northwest throughout the year was broken with November and December storms. The storms caused large amounts of rain and flooding in three separate events during the 2 months. Twelve Washington counties were declared Federal disaster areas. Northern Washington was affected by the December 2-3 flood, which resulted in five deaths and $14.8 million in damages. Southern Washington and northern Oregon experienced flooding on three different occasions. Flooding occurred in the Cowlitz River Basin in southwest Washingon and along the Columbia River in Oregon on November 25, December 2-3, and December 13-15. Flooding in the Willamette River Basin of Oregon occurred on November 25 and December 13-15. These floods caused $16.2 million in damages in the lower Columbia River Basin and along coastal drainages in Oregon.

Sources: USGS.