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Natrona County Historical Floods

LocationStart DateInformation
Casper, Garden CreekJul-1895Greatest recorded flood produced a 20-foot-high wall of water sweeping down Garden Creek, wiping out camp of settlers at present-day Westwood School. Three people drowned
Casper, North Platte River1-Mar-1906Flooding resulting from snow/ice melt, a diversion dam giving way, a stream returned to natural channel culvert too small to handle flood, rose against railroad embankment, earth gave way. Twelve were killed in a train wreck and a railroad bridge was damaged.
Big Horn River, Powder River, North Platte River, North Platte River tributaries near Casper27-Sep-1923Five days of widespread rainfall caused a 60- to greater than 100-year flood resulting in a railroad bridge washed out east of Casper. The event took 18 lives.
North Platte River, tributaries near Glendo1-May-1935Snowmelt and locally intense thunderstorms caused flooding. The flood was 10- to greater than a 100-year flood
Casper and vicinity6-Jul-1961High intensity rain showers caused considerable flash flooding in Casper and vicinity with numerous houses, cars and streets damaged. Some crop land damaged.
Big Horn River, North Platte River, Tongue River, Beaver CreekFeb-1962Snowmelt from warm Chinook winds (February) and rainfall runoff and/or snowmelt (May/June) caused a 25- to greater than 100-year flood
Casper 30 NW15-Jun-1962Several inches of 1- to 2-inch hail along with heavy rain caused considerable damage to range land, and to flocks of sheep in the area. Flash flooding occurred with resultant damage to roads and bridge.
Central Wyoming13-May-1965Heavy rains, especially in the central mountains, on top of the heavy snow of the 8th and 9th caused flash flooding on streams flowing out of the Laramie mountains between Wheatland and Casper. Damage to Bridges, roads, crops and housing was especially heavy from Glendo through Douglas to Glenrock.
North Platte River, Tributaries near Glendo1-Jun-1965Locally intense thunderstorms produced a greater than 50-year flood.
Casper15-Jul-1967Over 2 inches of rain in less than 2 hours caused flash flooding in Casper with damage to houses, stores, lawns, cars, etc. Estimated damage $1 million (WEMA Flood damage inventory, storm data)
Casper16-Jul-1968Nearly 1.5 inches of rain in an hour caused flash flooding in the central portion of Casper with damage to houses, lawns, streets, cars, and utilities.
Southeast Wyoming10-Jun-1970Heavy rains up to 6 inches in the Laramie Mountains from Casper to Wheatland caused flooding on the tributaries of the North Platte River. Some of the moisture fell as snow above 7500 feet elevation.
West of Casper6-Jul-1971Heaviest damage reported in suburban Red Butte Village. Some homes were demolished
Casper23-Jun-1974Heavy rain with soft hail up to 2.75 inches caused damage to houses, trees and cars. Rain caused brief minor flooding in downtown streets and into some stores to a few inches.
Central and North portions of Wyoming15-May-1978Heavy wet snow and record rains did very extensive damage to property, crops, and livestock in 12 counties. Hundreds of homes were damaged, and many totally destroyed. Numerous bridges and sections of roads were washed out, power lines downed, with much damage to cars and personal property. Total estimated damages came to $15.5 million. The following are discharge amounts from WEMA Storm Data: Fifteenmile Creek near Worland (May 18) - 4,270 CFS, Big Horn River at Worland (May 19) - 17,500 CFS, Nowood River near Ten Sleep (May 19) - 3,380 CFS, Shoshone River near Lovell (May 18) - 7,680 CFS), Elk Creek near Basin (May 19) - 2,450 CFS, Shell Creek near Greybull (May 19) - 2,150 CFS, Big Horn River near Kane (May 20) - 20,700 CFS, Little Powder River below Corral Creek near Weston (May 18) - 2,410 CFS, Little Powder River above Dry Creek near Weston (May 19) - 4,460 CFS, Little Powder River above Dry Creek near Weston (May 19) - 5,300 CFS, Salt Creek near Sussex (May 18) - 10,200 CFS, Dead Horse Creek near Buffalo (May 18) - 1,420 CFS, Clear Creek below Rock Creek 162? CFS, Powder River near Kaycee (May 18) - 4,200 CFS, Powder River at Sussex (May 19) - 24,000 CFS, South Fork River near Kaycee (May 20) - 8,200 CFS, Bitter Creek near Garland (May 17) - 552 CFS, Whistle Creek near Garland (May 18) - 2,340 CFS, Shoshone River below Buffalo Bill Reservoir (May 19) - 1,230 CFS, Shoshone River near Garland (May 19) - 4,550 CFS, Goose Creek below Sheridan (May 18) - 5,430 CFS, Prairie Dog Creek near Acme (May 19) - 3,940 CFS, Clear Creek at Ucross 1740 (May 19) - 32,500 CFS, Crazy Woman Creek at Upper Station (May 20) - 2,200 CFS, Little Thunder Creek near Hampshire (May 18) - 3,030 CFS, Black Thunder Creek near Hampshire (May 18) - 5,050 CFS, Turner Creek near Osage (May 18) - 2,480 CFS, Beaver Creek near Newcastle (May 19) - 3,870 CFS. The event was estimated to be a 20- to greater than 100-year flood
Casper19-Jun-1986Flash flooding occurred along Casper Creek. Extensive damage was reported just west of Casper. Over 2.5 inches of rain fell on the west side of Casper from 1730 to 1930 MST.
Casper8-May-1995Moderate to heavy rain fell in two counties. Amounts between 1.5 to 3 inches fell on already saturated soil. This produced some flooding of creeks and streams in two counties. In the Casper area, high water washed out sections of three roads and partially washed out two others.
9 SW Casper16-Jun-2003Rocks, boulders, mud and water were over Wyoming Highway 220 near mile marker 103.
Casper25-Jul-2005A line of strong thunderstorms moved west to east across Natrona County between 4:30 p.m. and 6:30 p.m. These storms originated over the Bighorn Mountains of Wyoming and rapidly intensified near the Natrona County International Airport, 6 miles west of Casper, where a 54 kt wind gust was reported. The airport received nearly an inch of rain between 5:35 p.m. and 6:05 p.m. The storms hit the Casper area between 5:50 p.m. and 6:20 p.m. with similar strong outflow winds followed by reports of up to 1.44 inches of rainfall over this 30 minute period. The brief torrent of rain produced flooding on the north side of downtown Casper, shutting down portions of Interstate 25. Portions of Poplar and McKinley streets near the interstate were also blocked with water and mud, which in some cases flowed into business buildings. The strong outflow winds that preceded the storm snapped the top of a cottonwood tree off of its 18 inch diameter trunk and ripped a sheet metal roof off a RV storage shed.
Casper3-Aug-2005In the early evening hours, a strong thunderstorm and its associated heavy rainfall neared the Casper area dropping a significant amount of rainfall. Within the city of Casper, rainfall totals ranged from 1 to 1.5 inches in less than an hour which led to an area of flash flooding. The rushing water moved cars several feet, approached the doorsteps and flooded the basement of several homes in the Allendale area, and caused an underground drainage pipe to give way causing a 20-foot wide sinkhole.
1 S Midwest29-May-2001Flash flooding along Teapot and Castle Creeks.
10 S Midwest to 5 S Midwest29-May-2001Flash flooding along Teapot and Castle Creeks.
Midwest29-May-2001Flash flooding along Teapot and Castle Creeks.
10 W Casper13-Jul-2004Minor flooding reported along Poison Spider Creek with water flowing atop Poison Spider Road. No damage or injuries occurred.