Denver

July 29-Aug. 2, 1956

Denver experienced a terrible week of torrential rain and flooding in 1956. In a downpour on Sunday, certain areas of Denver received up to three inches followed by another four inches Monday afternoon and evening. Rainfall on July 30 was widespread, caused by a weak cold front moving southward over the Denver area that met a warm moist bank of air moving in from the Gulf coast. On July 31, Denver experienced its “fourth near-cloudburst in five days”. This storm was centered over the southwest part of the city. The rain took a day off on August 1 and then a third-wave of rains came on August 2.

The type of flooding changed from day to day. Some areas of Denver suffered from three different floods in five days. On Monday evening, July 30, most flooding was caused by rainwater and overland flow. On July 31, Big Dry Creek, Little Dry Creek, and the Highline Canal all left their banks at the peak of the downpour; however overland flooding caused most of the costly damage. According to the Denver Post: “rushing rivers flowed through the city along previously uncharted channels, filling basements, ripping out paving and dumping tons of silt on lawns and in low-lying houses.” In addition, the flooding on August 2 was almost solely a result of overland flow.

On July 30, the flooding caused considerable damage to the Valley highway. Flooding in the surrounding area sent “torrents of muddy water cascading down ramps at Emerson and Downing”. “ Lake Downing ” was formed from the collected rainwater and it grew to be a block wide, 6 blocks long and up to eight feet deep. There was heavy damage to homes, cars, lawns, and streets in the Valverde area, University Park, College View, Harvey Park and Englewood.

In northeastern Colorado on July 30, Downtown Fort Morgan was flooded by two feet of water.

In the mountains west of Denver rockslides were reported on U.S. 285 north of Morrison and on state highway 7 south of Estes Park. A portion of U.S. 74 was washed out between Morrison and Evergreen. Two bridges were also partially washed out in that area.

On July 31, the flooding worsened and areas east of the South Platte River and South of Alameda were the hardest hit inside Denver city limits. Littleton and Englewood also sustained major damage and more highways and bridges were washed out in the metropolitan area. Rail service was disrupted as transportation over the main tracks near Littleton was closed. Nearly every major thoroughfare in south Denver and south-area suburbs was closed during the evening. Rowboats were trucked into the flood area from both Washington and City parks to be used to evacuate residents from flooded homes and stalled cars.

Before the third wave of flooding struck the night of August 2, Denver, Arapahoe, and Jefferson counties were designated flood disaster areas that afternoon. The flooding on August 2 was concentrated in the 25-square block Harvard Gulch area bounded by Broadway, S. University Blvd., E. Evans Ave., and E. Dartmouth Ave. Harvard Gulch was inundated for the third straight night. Another flood raced across the South High school athletic field, down Florida Ave. and into the sodden Valley Highway. These stricken areas actually received little precipitation. The rainfall was concentrated to the east and the flooding was from runoff water flowing from east to south.

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