ST. LOUIS (AP) — A large number of Iowa residents have required rescue due to extensive flooding that has impacted various parts of the state, submerging buildings up to their rooftops, blocking major roads, and disrupting essential services like electricity and drinking water.
Iowa Gov. Kim Reynolds mentioned that water levels in certain areas surpassed records from 1993, a flood that many in the Midwest still recall as the most severe in their lives. The flooding has affected parts of Iowa, South Dakota, Nebraska, and Minnesota.
The force of the water caused a train bridge connecting North Sioux City, South Dakota, to Sioux City, Iowa, to collapse. Additionally, water pressure around the Rapidan Dam in Minnesota prompted warnings of a potential dam failure.
The water levels are expected to reach their peak early this week, with some areas already experiencing the peak, and then the river crests are projected to move south towards the Missouri and Mississippi rivers.
“Businesses have closed, main streets have been affected. Hospitals, nursing homes, and other healthcare facilities were evacuated,” said Reynolds during a weekend press conference, describing the anticipated damages as “devastating.”
The situation is exacerbated by the hot weather, making the conditions even more hazardous.
Here is an explanation of why the flooding in the Midwest is so severe:
What is causing the severe flooding?
The primary cause of the flooding is heavy rainfall. The worst-hit areas were located south of Sioux Falls, South Dakota, where the airport received over 7 inches of rainfall. Similarly, Rock Rapids, Iowa, around 45 minutes east, recorded more than 11 inches of rainfall.
“There have been consistent rounds of rainfall throughout the month, with recent heavy downpours,” stated Joseph Bauers, a meteorologist with AccuWeather.
According to Shel Winkley, a weather and climate expert with Climate Central, a nonprofit organization focused on climate science, the hot air in the Northeast has directed storm paths through the Midwest, resulting in the recent severe storms and flooding.
The recent heavy rains have fallen on already saturated ground, which can no longer absorb additional moisture, causing the rainwater to run off into rivers and streams.
For a region that has experienced drought in recent years, the extensive rainfall that began in late April and early May, followed by intense storms on Friday and Saturday, represents a significant change.
What is a crest and why is it important?
A crest is the highest point that a river reaches before receding, and it is closely monitored by forecasters. It is crucial to understand when a crest is expected, how severe it will be, and how fast it is moving downstream.
Due to the extraordinary amount of rainfall that occurred in the region, rivers rose rapidly, and crests are imminent or have already occurred in some areas.
Sioux City Fire Marshal Mark Aesoph confirmed that the Big Sioux River stabilized on Monday morning at around 45 feet, more than 7 feet higher than the previous record.
South Dakota Gov. Kristi Noem stated that the James and Vermillion rivers are anticipated to crest on Wednesday. The flooding is more widespread than anticipated, which has helped mitigate the impact in certain residential areas. While it will raise the levels of the Missouri River, it will not be as significant as initially expected, as highlighted during a Monday press conference.
While the most intense rainfall has been concentrated in northwestern Iowa, parts of northeastern Iowa are forecasted to receive up to an inch of rain on Monday. This rainfall will take several days to travel through the state. Zogg also mentioned that the location of the rain is particularly concerning for Iowa, as it must pass through the entire river system before exiting.
As all the water eventually flows into the Missouri and Mississippi rivers, widespread flooding is expected along these major rivers. Additionally, there is a possibility of more rainfall later in the week.
“When it comes to rainfall and river response, location, timing, and volume will determine how the river reacts and whether the flooding situation worsens,” explained Zogg.
Is this linked to climate change?
Flooding and heavy rainfall are not uncommon in the Midwest, particularly in June. However, connecting any specific heavy rainstorm to climate change is a challenging task, as noted by Winkley.
Due to greenhouse gases warming the planet, the atmosphere is capable of holding more moisture, leading to heavier rainstorms that can overwhelm infrastructure and cause floods. Winkley also mentioned that severe floods are becoming more frequent.
“The extremes are becoming more extreme,” emphasized Winkley.
Reporters from the Associated Press, Hannah Fingerhut in Des Moines, Iowa, and Margery A. Beck in Omaha, Nebraska, contributed to this report.
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