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Community-based Inundation Maps Available on IFIS
As floodwaters rise, our anxiety levels often do too. But this time around, Iowans have new sources of reliable information to turn to, thanks to the Iowa Flood Center (IFC) at the University of Iowa.
The IFC offers Iowans a set of readily accessible online tools through the Iowa Flood Information System (IFIS). IFIS provides maps and up-to-date information about community-specific flood conditions across the state.
Flood inundation maps of 10 Iowa communities are particularly useful during flood events to help people visualize the potential extent of flooding at a range of river levels. This information can help individuals and communities plan and make sound mitigation decisions, and allows homeowners, business owners, and others see how predicted flood levels might affect their property.
IFIS includes a full set of flood inundation maps for the following communities (click a community to view the map):
- Des Moines
- Ames
- Spencer
- Mason City
- Charles City
- Waterloo/Cedar Falls
- Cedar Rapids
- Iowa City
- Hills
- Elkader
Nathan Young, associate director of the Iowa Flood Center, says the IFC has been developing flood inundation maps since the center was launched four years ago. “This is an opportunity for us to apply research that is useful and meaningful for Iowans,” he says. “Our maps demonstrate not just a 100-year flood or a 500-year flood, but also the extent of the flooded landscape with every six-inch rise in the projected flood level. We believe this extra measure of preparedness can save property, resources, and lives.”
To access IFIS, visit ifis.iowafloodcenter.org. From this page, you can launch IFIS or view a brief tutorial on how to use the system. To view flood inundation maps for one of the communities listed above, users should select “Flood Map Libraries” from the Flood Maps menu option on the IFIS dashboard and select the appropriate community. The flood map controller slide bar on the right allows users to see the potential extent of flooding at any selected stage or discharge.
IFIS uses a Google maps interface, so users can zoom in and out, switch to different views (satellite and street view), and navigate around the map.
Maps for additional communities are added to IFIS each year. For additional information on the development of the community-based flood inundation maps, visit: http://iowafloodcenter.org/projects/flood-inundation-maps/.
Complicated Waters: Mapping Kalona
On June 15, 2010, the city of Kalona, Iowa, was soaked with more than two inches of rain in about an hour. Flash flooding from a nearby drainage ditch forced the evacuation of a mobile home park, where residents found themselves suddenly knee-deep in water.
The floodwaters receded quickly, and, compared to other floods in Iowa, this event could be considered minor. But Kalona is facing flooding issues that are actually quite complex. For more than two years, the city has been working to understand and modify a proposed floodplain map of the community presented by FEMA, the Federal Emergency Management Agency. The original FEMA maps, which delineate the 100-year-floodplain (areas with a 1 percent chance of flooding each year, independent of previous years), would have cost Kalona property owners over $1 million in annual flood insurance premiums.
Shortly after the FEMA maps were initially released in 2010, the Kalona City Council invited the Iowa Flood Center (IFC) to help evaluate the maps. IIHR Director Larry Weber and IFC Associate Director Nathan Young met with the Kalona City Council several times over the ensuing year and a half to explain the floodplain mapping methodology and discuss opportunities to refine the Kalona map.
The IFC team studied the methods used to create the maps and reran the models. At the Sept. 19, 2011, Kalona City Council meeting, Weber presented the results of IFC’s own 2D modeling of the Kalona area. The map looked quite a bit different than the FEMA original. Using LiDAR (laser radar) data to develop a digital elevation model, the IFC team modeled the geometry of the river and creek beds, as well as the surrounding area.
“This is a more advanced engineering approach,” Weber explained. “And it’s more appropriate.”
The new maps underwent another round of revisions when the IFC team applied a major precipitation event to the model. This added layer of complexity better shows where the true risk is, Weber explained. “We wanted to be able to provide the best kind of map.”
Working with FEMA and the Iowa Department of Natural Resources, the maps underwent a thorough review process and were presented to the public for comment on October 4, 2012. The new maps became effective last month, January 2013.
Using the new map, Kalona’s flood insurance tab has been cut in half. The services of the Iowa Flood Center have been crucial to Kalona as the town finds its way through a complicated and costly situation, says City Administrator Ryan Schlabaugh. “The goal was to have the most accurate map possible,” he says, “and the Iowa Flood Center helped us do that.”
Although the process has by no means been a simple one for Kalona, the community is in effect leading the way through complicated waters.
Maps delineating the 100-year floodplain in Kalona can be viewed by visiting the City of Kalona website.
Flood Inundation Map: Mason City
Center Develops Web-Based Flood Map for Mason City
A new web-based flood preparedness tool developed at the Iowa Flood Center (IFC) can help Mason City residents know what to expect from the Winnebago River at times of high flows.
The new Mason City flood inundation maps are available to the public on the Internet through the Iowa Flood Information System (IFIS), an interactive Google Maps-based online application. Homeowners and business owners will now be able to see how predicted flood levels might affect their individual properties.
Nathan Young, IFC associate director, says improving flood preparedness is one of the IFC’s key goals. “This is an opportunity for us to produce research that is useful and meaningful for Iowans. Our high-resolution web-based flood inundation maps illustrate where floodwaters will go under different conditions.
He adds, “We believe this extra measure of preparedness can save property, resources, and lives.”
With these maps, Iowa Flood Center researchers are taking the guesswork out of future flood scenarios for Mason City and several other Iowa communities. When floods struck Iowa in the past, uncertainty was part of the problem. Property owners were unsure if projected floodwaters would reach them, and how they ought to prepare.
“The models and information provided by the Iowa Flood Center are another set of tools for our city to use in planning for a flooding event,” says Mason City City Administrator Brent Trout. “We need information like this to better understand and predict where flooding will occur first, so we can put our resources at the correct location.”
Trout adds, “We appreciate IFC completing this for our community.”
IFC engineers use bathymetric surveys of the riverbed to determine the shape of the channel and aerial LiDAR (laser radar) data. With this information, researchers can create very detailed maps of the streambed and floodplain to illustrate where floodwaters will go under different conditions.
The detailed flood inundation maps are available online for a number of Iowa communities including Cedar Rapids, Charles City, Des Moines, Elkader, Hills, Iowa City, and Waterloo/Cedar Falls. Additional communities will be mapped in the future.
To use the interactive online maps, visit the Iowa Flood Information System (IFIS). Launch IFIS, and click “Flood Maps” to view the inundation maps.
The Iowa Flood Center is part of IIHR—Hydroscience & Engineering, a unit of the UI College of Engineering. The IFC was created in 2009 in the aftermath of the historic 2008 Iowa floods and is supported by state appropriations to improve flood monitoring and prevention in Iowa.
MEDIA CONTACT: Sara Steussy, Iowa Flood Center, 319-384-1729, sara-steussy@uiowa.edu
Flood Inundation Map Demonstration: Mason City
Iowa Flood Center to demonstrate web-based flood map for Mason City on Monday, July 2
A new Internet-based flood inundation map developed at the Iowa Flood Center at the University of Iowa will be demonstrated during the regular meeting of the Mason City City Council on Monday, July 2.
Iowa Flood Center Associate Director Nathan Young will demonstrate and describe how the new web-based tool will provide property specific flooding level information to help Mason City homeowners and businesses better prepare for future floods.
What
Demonstration of web-based flood inundation map for Mason City
When
7:00 p.m., Monday, July 2, 2012 at the regular meeting of the Mason City City Council
Where
Mason City Public Library, Mason City Room, 225 2nd Street SE
Who
Nathan Young, Associate Director of the Iowa Flood Center and Associate Research Engineer at IIHR—Hydroscience and Engineering will demonstrate and describe the new flood maps developed for Mason City.
MEDIA CONTACT: Sara Steussy, Iowa Flood Center, 319-384-1729, sara-steussy@uiowa.edu
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The Iowa Flood Center (IFC) is part of IIHR—Hydroscience & Engineering, a unit of the University of Iowa’s College of Engineering. The IFC was created in 2009 in the aftermath of the historic 2008 Iowa floods and is supported by state appropriations to improve flood monitoring and prevention in Iowa.
For more information about the Iowa Flood Center, visit iowafloodcenter.org.
Flood Inundation Map: Elkader
A new web-based flood preparedness tool developed at the Iowa Flood Center (IFC) can help Elkader residents know what to expect from the Turkey River at times of high flows.
The new Elkader flood inundation maps are available to the public on the Internet through the Iowa Flood Information System (IFIS), an interactive Google Maps-based online application. Homeowners and business owners will now be able to see how predicted flood levels might affect their individual properties.
Witold Krajewski, IFC director, says improving flood preparedness is one of the IFC’s key goals. “This is an opportunity for us to produce research that is useful and meaningful for Iowans. Our high-resolution web-based flood inundation maps illustrate where floodwaters will go under different conditions.”
He adds, “We believe this extra measure of preparedness can save property, resources, and lives.”
With these maps, Iowa Flood Center researchers are taking the guesswork out of future flood scenarios for Elkader and several other Iowa communities. When floods struck Iowa in the past, uncertainty was part of the problem. Property owners were unsure if projected floodwaters would reach them, and how they ought to prepare.
IFC engineers use bathymetric surveys of the riverbed to determine the shape of the channel and aerial LiDAR (laser radar) data. With this information, researchers can create very detailed maps of the streambed and floodplain to illustrate where floodwaters will go under different conditions.
The detailed flood inundation maps are available online for a number of Iowa communities including Cedar Rapids, Charles City, Des Moines, Elkader, Hills, Iowa City, Mason City, and Waterloo/Cedar Falls. Additional communities will be mapped in the future.
To use the interactive online maps, use the Iowa Flood Information System (IFIS). Launch IFIS, and click “Flood Maps” to view the inundation maps.
The Iowa Flood Center is part of IIHR—Hydroscience & Engineering, a unit of the UI College of Engineering. The IFC was created in 2009 in the aftermath of the historic 2008 Iowa floods and is supported by state appropriations to improve flood monitoring and prevention in Iowa.
MEDIA CONTACT: Sara Steussy, Iowa Flood Center, 319-384-1729, sara-steussy@uiowa.edu
National Weather Service Adopts IFC Maps
Predicting the impact of flooding in the past brought with it a lot of guesswork. Now predicting the impact of a flood may be able to be accomplished with a little more certainty thanks to the work of the Iowa Flood Center.
Listen: New Mapping System Prepares Iowans for Floods
Listen to this week’s Iowa Environmental Focus radio spot for information on the Iowa Flood Center flood inundation maps.
