Residents evacuated due to flooding in Western Montana


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The Clark Fork River runs through the center of Missoula, carrying water down from the mountains. (Frank Fujimoto/flickr)

Jenna Ladd | May 9, 2018

Sixty homes in Missoula, Montana were mandatorily evacuated due to flooding on Tuesday.

Heavy precipitation during early May and recent snowmelt from nearby mountains mixed to send rivers and streams in several parts of Western Montana flowing out of their banks. The Clark Fork River is a main artery running through the middle of Missoula and is the site of the most severe flooding. 1,300 homes along the river were encouraged to prepare for a possible evacuation.

Ken Parks is the Missoula County Disaster and Emergency Services deputy coordinator. He said to the Associated Press, “If you live anywhere near a stream or waterway in western Montana you need to be prepared to leave your home. This is going to come earlier than we expected. We’re trying to get out ahead of this thing and get the message out that this could be a very dangerous situation.”

From 1955 to 2016, snowpack on mountains in the Western United States declined by an average of 23 percent, according to the U.S. Environmental Protection Agency. However, Western Montana has really only seen the beginning of this spring’s snowmelt, according to authorities from the National Weather Service. Some parts of the local mountain range are expected produce 55 additional inches of snowmelt through the spring and summer. The Clark Fork River is expected to reach higher levels than it has since 1981 this year.

More mudslides possible for southern California


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Rescue workers wade through debris and sediment following last week’s mudslide in Santa Barbara county, California. (Associated Press/Marcio Jose Sanchez)
Jenna Ladd | January 17, 2018

Meteorologists warn that rainfall during the fourth week of January could trigger another mudslide in southern California, where residents of Santa Barbara county are still reeling from last week’s massive landslide. Between two and five inches fell in the county between January 8th and 9th, sending boulders and thick sediment raining down on Montecito, California. A recent wildfire in the area left mountain slopes without vegetation to slow down the runoff and played into the destruction of 115 homes and the death of at least 20 people.

Jonathan Godt of the U.S. Geological Survey told the New York Times, “It was pretty rare, in essence a worse-case scenario from that standpoint. The same rainfall that falls on a burned landscape can cause a lot more damage than it would before a fire.”

AccuWeather officials have predicted that a shift in the jet stream will bring more moisture from the Pacific Ocean into southern California’s atmosphere by January 23rd and 24th. They caution that the weather pattern presents the risk for “locally heavy rainfall, flash flooding and a significant risk of mudslides.” Their report states that areas surrounding Point Conception, California are most likely to be affected.

February and March are heavy precipitation months for Santa Barbara county, and following California’s record-setting year for wildfires, conditions are right for faster-moving and more destructive landslides.

AccuWeather meteorologist Evan Duffey said, “People need to leave the area by evacuation deadlines as they are given. Once a mudslide begins, there may only be minutes to seconds before a neighborhood is wiped out.”

CGRER members Jerry Schnoor, Larry Weber and Gene Takle share climate and flood prevention expertise with Iowans


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The Iowa River overflows onto the University of Iowa campus following the 2008 flood. (rachaelvoorhees/flickr)
Jenna Ladd | October 18, 2016

In the face of more frequent flooding and much heavier rains, it is estimated that Iowa will need $4 to $5 billion to protect its communities moving forward. 

Flood mitigation efforts in the state thus far have centered around building levees, flood walls, and protecting utilities, but Iowa researchers have found that upstream structures like wetlands and detention pounds are an effective means of flood prevention. Sen. Rob Hogg of Cedar Rapids said that some lawmakers have acknowledged the need to ramp up these strategies, but the conversation is often buried by health care and education budget arguments. Hogg said, “If you can’t reach agreement over funding the basics, it’s really hard to get to the next level, to discuss funding water management.”

The increasing frequency of extreme rainfall may demand that flood mitigation take center stage at the capital. “We were hard-pressed to get 4-inch rainfalls 100 years ago, and now it’s very common,” said Jerry Schnoor, co-director at the University of Iowa’s Center for Global and Regional Environmental Research. Eugene Takle, director of the climate science program at Iowa State University, agreed, “In the Cedar River basin, we found the 100-year flood a century ago is now very likely to be a 25-year flood.” The Cedar basin’s record flood in 2008 had a $5 billion price tag.

Takle and other experts say these changes are primarily due to climate change. Rising greenhouse gases in the atmosphere allow it to hold more water vapor. “When you have more water vapor, you can expect more rain events,” he said. Takle’s data support this claim: atmospheric water vapor has increased by 31 percent in the winter months since 1970 and by 14 percent in the spring; average annual rainfall in Iowa has risen by 33 percent since 1970. Takle said, “This is consistent with what the climate models said would happen. The Midwest has experienced a big increase in extreme events.” According to NOAA National Centers for Environmental Information, Iowa has had 26 flood disasters with damages adding up to more than $1 billion since 1980.

Larry Weber, director at the University of IIHR – Hydroscience & Engineering, parent organization of the Iowa Flood Center, said that the loss of prairie potholes and wetlands, which can soak up heavy rainfalls, has contributed to these flooding events. He said, “We’ve taken away a lot of those natural storage areas.”

Iowa lawmakers passed a sales-tax funding plan in 2012 to provide $1.4 billion in flood prevention structures, but more funding is needed. Eight-nine towns and cities have identified $35 million in flood prevention structures that do not have funding. Some Iowa lawmakers are working to increase the sales tax by three-eighths of 1 cent in order to fund the Natural Resources and Outdoor Recreation Trust Fund, which would provide $180 million each year to restore wetlands, protect wildlife habitat, reduce runoff and improve trails, and more.

One and a half million dollars in federal supplemental aid money allocated to the Iowa Flood Center’s Iowa Watersheds Project after the 2008 flood has reduced flooding downstream by 15-20 percent in the Otter, Beaver and South Chequest watersheds. The center received $98 million in federal grant money this year for similar flood mitigation projects in 25 additional watersheds. Weber said, “We’re making great strides in the places where we work, we just need to be working in more places — whether it’s through our projects, or the work of other state and federal agencies, private landowners, and nonprofit groups.”

UI study finds increase in heavy rainfall in upper Midwest


Photo by turtlemoon, Flickr.
Photo by turtlemoon, Flickr.

A study from the University of Iowa shows that heavy rainfall has become more frequent in the upper Midwest over the last 60 years.

This could be related to an increase in temperature in the region since warmer surface temperatures allow for more water to be absorbed by the atmosphere.

Read more about the study here.

On the Radio: Increasing an understanding of erosion


Photo by bishib70, Flickr

Check out this week’s radio piece here.  It discusses the impacts of soil loss on Iowa farmers.  You can also read the transcript below:

A group of agronomists at Iowa State University wish to increase awareness of one of Iowa’s greatest environmental issues: topsoil erosion. Continue reading