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Catastrophic Flooding in Yellowstone – Historic Destruction of Homes, Roads and Bridges

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Yellowstone National Park has seen historic flooding, with rivers cresting heights not seen in 100 years.

Melting snow and heavy rains have caused historically high water levels in Yellowstone National Park, which have destroyed homes, roads and bridges, and isolated some of the national park’s gateway communities.

This year has been historic for Yellowstone National Park in more ways than one. Founded in 1872, America’s first national park celebrates its 150th anniversary. It has also suffered extraordinary flooding, with rivers rising to heights not seen for 100 years.

During the second week of June 2022, an atmospheric river—a narrow band of tropical moisture—soaked the Pacific Northwest before dumping several inches of rain on northern Wyoming and southern Montana. The flooding coincided with a heat wave that added to the melting of the thick snow cover.

“This has led to flooding rarely or never seen before in many rivers and streams in the region,” according to the National Weather Service (NWS) in Billings, Montana.

2022 Yellowstone floods annotated

June 16, 2021 – June 16, 2022

On June 13, park officials closed Yellowstone, which spans 2.2 million acres (8,900 square kilometers) in northwest Wyoming, southwest Montana and eastern ‘Idaho, and announced the evacuation of more than 10,000 visitors for safety reasons. Campsites were flooded, roads were washed out and rocks fell on the roads.

Despite a slow start to the 2021-2022 hydrological year, a cool and wet spring brought much-needed water to the region, which experienced drought conditions. In April, above-median precipitation in the Yellowstone Basin contributed to ground snowpack accumulation, which had risen to near the 30-year median by May. The Moderate Resolution Imaging Spectroradiometer (MODIS) on " data-gt-translate-attributes="[{" attribute="">NasaThe Terra de’s satellite captured these images comparing the snowpack on June 16, 2022 to the snowpack on the same date in 2021.

Between June 10 and 13, the Absaroka and Beartooth Ranges received between 0.8 and 5 inches of rain, which combined with 2 to nearly 5 inches of snowmelt, according to the Billings NWS. The combined rain and snowmelt, equivalent to 4 to 9 inches (10 to 22 centimeters) of rain, poured over already wet ground.

Yellowstone Soil Moisture 2022 Annotated

May 30, 2021 – June 6, 2022

The maps above show the soil moisture anomaly in northern Wyoming and southern Montana during the week leading up to the storm. The maps were constructed with data from the Crop Condition and Soil Moisture Analytics (Crop-CASMA) product. Crop-CASMA integrates measurements from NASA’s Soil Moisture Active Passive (SMAP) satellite and vegetation indices from MODIS instruments from NASA’s Terra and Aqua satellites. The map on the left shows soil moisture conditions between May 30 and June 5, 2021, when the state was experiencing more severe drought conditions. The image on the right shows soil moisture conditions from May 31 to June 6, 2022, just before the rains.

The runoff flooded the Yellowstone, Stillwater, and Clarks Fork rivers and their tributaries. At Corwin Springs, north of Gardiner, Montana, the Yellowstone River peaked at 13.88 feet on June 13, 2022, breaking the previous record of 11.5 feet set on June 14, 1918. A record river flow of 51,400 cubic feet per second was also measured. that day, beating the previous record flow of 32,200 cubic feet per second in 1996, according to flow gauges from the US Geological Survey.

North of the park, Gardiner and Cooke City were cut off by rising floodwaters, which washed away roads and bridges, washed away several homes and inundated hundreds more. Rock Creek destroyed several bridges and flooded businesses in historic downtown Red Lodge, Montana. The floods also caused power outages and compromised drinking water supplies in several towns.

The northern part of the park, where the river flows through steep canyons, suffered the most damage when the Yellowstone River cut a new course. The road between Gardiner and park headquarters near Mammoth Hot Springs, a main supply route in the park, was washed out and is expected to take months to repair.

The southern part of the park suffered less flood damage. On June 22, 2022, the west, south and east entrances were reopened along with the south loop road, allowing visitors access to Old Faithful. The north and northeast entrances to the park are closed indefinitely.

NASA Earth Observatory images by Joshua Stevens, using soil moisture data from Crop Condition and Soil Moisture Analytics (Crop-CASMA) and MODIS data from NASA EOSDIS LANCE and GIBS/Worldview.