Rapid spring melt after a winter of heavy snow has been the most common cause of major floods in Utah history.
Flash floods, landslides, and disasters caused by collapsed dams also resulted in some of the worst damage recorded in the state.
The Utah Floodplain and Stormwater Management Association provides the following rundown of Utah's biggest and most destructive floods.
-- Mark Shenefelt, Standard-Examiner
July 4, 1884
Flooding in the Colorado River drainage, greater than a 100-year event, occurred due to rapid snowmelt combined with rainfall.
April 13, 1923
Tributaries to the Great Salt Lake between Brigham City and Salt Lake City were flooded due to intense thunderstorms. Seven people were killed and damage was estimated at $3 million. Much of Willard and Perry were under water.
April 28, 1952
Melting of a record snowpack caused severe flooding on the Ogden and Weber rivers and several others in the state. Authorities declared a flooding disaster. Two people were killed in boat wrecks on the swollen Ogden River. Flood damage totaled $8.4 million, including $1.9 million in Salt Lake City.
June 16, 1962
Ashley Creek and other streams in the Manila and Vernal areas flooded after three days of intense snowfall on thick snowpack above 9,200 feet elevation. Seven died and damage reached $814,000.
Dec. 6-7, 1966
The Virgin and Santa Clara rivers flooded after four days of heavy rainfall, causing $1.4 million in damage.
Aug. 1-2, 1968
Cottonwood Wash and other San Juan River tributaries flooded after intense rainfall followed by 11 days of rainfall.
Sept. 5-7, 1970
The San Juan River and its tributaries flooded after record rainfall. Two deaths occurred and damage was estimated at $700,000.
Aug. 27, 1972
Vernon Creek in Tooele County flooded after intense thunderstorms.
April 27-June 25, 1983
Major rivers and their tributaries flooded due to rapid melting of snowpack, resulting in record streamflows. Salt Lake City's State Street became a river. A presidential disaster was recorded and damage was estimated at $621 million.
Thistle landslide, 1983
A major landslide occurred in Utah County above the town of Thistle. The landslide blocked the Spanish Fork River, which flooded the town of Thistle until it was under water. The event caused one death and two injuries as well as damages topping $200 million.
April 17-June 20, 1984
Widespread river flooding from above-average snowpack caused an estimated $41 million damage statewide.
May 22, 1984
After two years of heavy discharges from upstream reservoirs on the Sevier River, totaling 1.5 million acre feet of water, Sevier Lake was measured to be as much as 35 feet deep after being nearly dry since about 1880.
June 15, 1984
Three years of runoff from greater than normal precipitation increased Utah Lake’s level to a 101-year record of 5.46 feet above maximum level. Authorities paced damage at $5.9 million.
June 3, 1986
Large runoff from above-average precipitation since September 1982 increased the Great Salt Lake’s level to a 140-year record elevation of 4,211.85 feet above sea level. The spreading lake caused $268 million in damage. In response, the state built massive pumps to drain lake water into the west desert.
July 11, 1999
The Davis-Weber Highline Canal breached through its concrete lining, eroding the sand embankment and flooding 30 Riverdale homes. The break pushed 67,000 cubic yards of sand and silt into the subdivision. Losses to homes and agriculture were estimated at $50 million.
Jan. 10, 2005
Several weeks of heavy storms caused significant flooding along the Santa Clara and Virgin rivers, killing one person who was trapped in a vehicle near Quail Creek Reservoir. Ash Creek, normally dry and three feet wide, became a torrent 300 feet wide in places. Damage was estimated at $300 million and a presidential disaster was declared.
Heavy, frequent rainfall, warm spring temperatures and a quickly melting large snowpack caused flooding and landslides in nine counties. Damage totals hit $2.9 million.
July 11, 2009
A Logan hillside collapsed, blocking an irrigation canal. The obstruction sent tons of water and debris cascading into a neighborhood below, destroying a home and killing three people inside. Eight other homes were seriously damaged.
Water and debris flow from springtime snowmelt caused an estimated $1 million damage statewide.
Four days of winter storms delivered 16.4 inches of rain and 15.3 inches of snow, causing $6 million in damage to homes, bridges and roads in southern Utah.
Eighteen counties reported damage totaling $12.7 million as a heavy snowpack, a rapid melt and rain caused flooding in many rivers. The upper branches of the Ogden River and the lower Weber River were among the hardest-hit areas.
Sept. 12, 2012
The Laub Reservoir Dam west of St. George collapsed, inundating neighborhoods in Santa Clara, Ivins and St. George. Authorities said 66 homes, 18 businesses, roads, sidewalks, sewer lines and golf courses were damaged, totaling $3.9 million.