Flash Flood Alley Segements

 

Floods in Morrison, Colorado

The town of Morrison, in Jefferson County, Colorado, lies in an area subject to very rapid runoff and an overall region that has experienced many floods.

Helpful Links:

Excellent background on floods in the Bear Creek Drainage Basin

Significant Front Range Floods

City of Morrison information on flood events

A USGS report on Major Floods and Droughts in Colorado

This scene is from the Jefferson County Flood Hazard Map

July 24, 1896

A large rainfall event - centered around Cub Creek near the town of Evergreen in Jefferson County - affected areas surrounding Morrison (Jefferson Co.).

  " Intense rainfall on 24 July 1896 centered on Cub Creek, a tributary of Bear Creek near Evergreen. "Without a moment's warning the largest flood that ever came down Bear Creek struck Morrison about 8 o'clock (July 24), sweeping everything in its path ... although the water came down through the town nearly 3 feet deep in the main street, the buildings in the business section all withstood it." Twenty-seven lives were lost in the flood (available records do not indicate where the deaths occurred) and severe damages were reported from Evergreen to the mouth of Bear Creek. No rainfall records of this flood are available. The peak flow on Bear Creek at the Morrison gauging station was estimated at 8,600 cfs, which is the flood of record for the gage. The most recent hydrologic studies indicate that this flood would have a one in 40 chance of occurring in any year. It is not known to what extent Mount Vernon Creek contributed to the Morrison flooding."

References:  

http://alert.udfcd.org/bear_history.html

http://town.morrison.co.us/history/events.php

The 1938 flood exceeded today's 100-year regulatory flood elevation by as much as four feet.

September 2-3, 1938

"An unofficial report stated that 7.9 inches fell just north of Morrison in six hours. The heaviest rainfall centered on the divide between Bear Creek and Mount Vernon Creek. The peak discharge on Bear Creek at Morrison above Mount Vernon Creek was 6,200 cfs. From post flood measurements the Mount Vernon Creek peak discharge was estimated at 9,230 cfs at a point 1/2 mile upstream from Morrison. From statements by local residents it appears that the peak discharge on Mount Vernon Creek reached Morrison at about 7 p.m., preceding that on Bear Creek by 1/2 hour. Six people drowned when trapped in their automobile between Morrison and Kittredge. Damages in the basin were estimated at $450,000. If Morrison had not been warned, or if the flood had occurred late at night, the number of deaths would likely have been considerably higher. The photograph to the left shows the relative level of this flood compared with the 100-year flood level. Note that this flood appears to have exceeded today's 100-year regulatory flood elevation by as much as four feet.

References:

http://alert.udfcd.org/bear_history.html