Flood — Sioux, Iowa

2024-06-20 to 2024-06-25 · near Chatsworth, Sioux, Iowa

Event narrative

Rainfall amounts across Sioux County from June 20-22 ranged from 2 to 7 inches, with the highest amounts across the northern half of the county. Farther north and upstream, up to 12 inches of rain fell across portions of southeast South Dakota and northwest Iowa. This rainfall resulted in extensive overland flooding and major to record flooding along the Big Sioux, Rock, West Branch Floyd, and Floyd Rivers, and Burr Oak Creek.

Large sections of Rock Valley and Hawarden were evacuated as flood waters inundated both cities. An estimated 200 people were rescued during the peak of the flooding. An estimated 60 businesses were impacted by flood water in Rock Valley and Hawarden. County-wide, 700 to 800 housing units were impacted by flood water, 150 of which were declared a total loss. Rock Valley Public and Christian Schools were also flooded and sustained severe damage.

Countless county roads and bridges were covered in water and damaged. Preliminary damage assessments estimate loss to public infrastructure to be 6.5 million dollars.

One direct fatality occurred in Rock Valley when a man was pinned by debris from a collapsed foundation and subsequently drowned when water filled the basement.

The majority of overland flooding subsided by June 25, but river flooding continued through the end of the month. For additional information on river flooding, please see other flood entries for Sioux County.

Wider weather episode

A multi-day significant heavy rainfall event from June 20-22 resulted in widespread rain totals between 5 and 10 inches across portions of southeast South Dakota, northwest Iowa, and southwest Minnesota. As rainfall reached area streams and rivers, major to record flooding was observed, devastating several towns and communities. Extensive overland flooding also resulted in significant impacts and damages. All river crest information is preliminary until made official by the gauge owner.

A Presidential Disaster Declaration was signed for Buena Vista, Cherokee, Clay, Dickinson, Lyon, Plymouth, O'Brien, Osceola, Sioux, and Woodbury Counties.

View location on OpenStreetMap → (42.9171, -96.5259)

Source: NOAA Storm Events Database, event_id 1195645. Narrative written by the NWS forecast office that issued the report.