Name: 113,000 more properties may be at risk of flooding in Indiana than previously thought, report says
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113,000 more properties may be at risk of flooding in Indiana than previously thought, report says

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Indianapolis StarView CommentsMore than 282,500 Indiana homes, businesses and other structures are at substantial risk of flooding, about 67&nbsp;percent more than the government currently estimates, That study calculates that 113,600 Indiana properties that are not&nbsp;currently in a mapped floodplain&nbsp;are at risk of flooding, representing an enormous potential cost to homeowners and the&nbsp;government alike.Many neighborhoods across the state, from Mishawaka and&nbsp;South Bend&nbsp;to Indianapolis&nbsp;are particularly vulnerable, according to the analysis.&nbsp;The problem, researchers say, is that Federal Emergency Management Agency floodplain maps are sometimes based on decades-old data, whereas global warming and urbanization have changed&nbsp;rainfall and drainage patterns. Updating the maps would be expensive, but not doing so could have dire consequences as cities approve&nbsp;construction in flood-prone areas.Updating the maps could also erode property values&nbsp;in areas added into a 100-year&nbsp;floodplain, and put the burden of flood insurance on some families — at an average of in Indiana.To assess current flooding risk, the nonprofit research group &nbsp;employed researchers from several major universities, including Columbia University and the Massachusetts Institute of Technology,&nbsp;who created a new modeling system based on decades of research.Is your home at risk of flooding?:The First Street Foundation report that environmentalists and researchers have had for years. Advocates for updated floodplain maps, including researchers at the First Street Foundation, say it’s important for these maps to&nbsp;meet the changes to come with&nbsp;global&nbsp;warming.A major concern of some experts, climate change predictions are forecasting&nbsp;heavier rainfall in the spring and winter, meaning&nbsp;flood protection may become even more vital in the coming decades.&nbsp;The older data supporting some floodplain maps&nbsp;also may not take into account urban expansion that has paved&nbsp;over permeable surfaces.The combination may result in more rain falling all at once, and fewer places for it to go when it lands.&nbsp;“It’s important that we understand that our climate isn’t stable. It has not been stable, it’s much wetter than it used to be,” said Jeff Dukes, director of the Purdue Climate Research Center. “If our flood maps are based on yesterday’s climate, then they’re not going to be correct for tomorrow’s floods.”Floodplain maps are based on&nbsp;100-year floods, weather events that have&nbsp;a 1% chance of happening each year.Siavash Beik, principal engineer for Christopher B. Burke Engineering,&nbsp;said these maps are often made by calculating&nbsp;three variables: rainfall, topography, and&nbsp;hydraulic analysis, which evaluates the capacity of a stream or other water body.&nbsp;The process is, unsurprisingly, time consuming, Beik said —&nbsp;and expensive.The Association of State Floodplain Managers&nbsp;said it would cost to finish drawing floodplain maps&nbsp;for the whole country. In recent years, the mapping program's budget has been a couple of a million dollars, and recent severe events haveCOVID-19:David Johnson, an assistant professor of political science and industrial engineering at Purdue University, said this is part of the reason why updating floodplain maps can fall a few years —&nbsp;or decades —&nbsp;behind schedule."That has been one criticism of FEMA flood maps, that they aren't updated often enough," Johnson said. "The other issue is just that they are looking at the current risk, but not forward-looking. So it's just a snapshot of risk at the time the study was done, but it's not accounting for climate change or further urban development."Climate change analyses are increasingly predicting that flooding will become a major concern for American cities. According to&nbsp;,&nbsp;annual&nbsp;rainfall has increased by 15% since 1895, a trend that is anticipated to continue —&nbsp;and possibly accelerate."There’s been already a dramatic increase in precipitation in Indiana over the last several decades," Dukes said. "The average stream flows are going to be greater, basically, throughout winter and spring.&nbsp;&nbsp;And those are the times of year where we typically have our highest flows anyway.”Aside from applying&nbsp;global climate models, the First Street Foundation's methodology also takes into account&nbsp;impermeable surfaces that play a role in city flooding. The model also fills in some&nbsp;gaps&nbsp;of&nbsp;FEMA mapping, compiling data from regions that have not previously had flood modeling or data.&nbsp;Beik said the foundation's methodology is&nbsp;"excellent" for gaining greater understanding on&nbsp;just how&nbsp;many properties are likely in a flood zone. He said he very much supports this type of calculation for seeing the larger picture&nbsp;on a national, state and even ZIP-code level.&nbsp;However,&nbsp;Johnson said,&nbsp;the foundation did&nbsp;make&nbsp;some "simplifying assumptions" he believes might affect the reliability of the data."They may be overestimating risk in some areas, and they might be underestimating risk in other areas," he qualified.&nbsp;For the large part, Indiana's floodplain maps are in better shape than those in many other states, Beik said. While he acknowledges some of them are as much as 20 years old,&nbsp;they&nbsp;have all been digitized and are .&nbsp;Marion County's floodplain maps were last updated in 2016, a spokesperson for the Department of Natural Resources said.&nbsp; breaks down ZIP codes with the estimated number of properties at substantial risk of flooding in a 100-year flood. In Indianapolis, ZIP code 46205&nbsp;— home to the Friends and Neighbors, Mapleton-Fall Creek, Watson McCord and Oakhill neighborhoods&nbsp;— is listed to contain&nbsp;the most properties at risk in the city. The report estimates about 2,500&nbsp;properties lie within the flood zone in this ZIP code, about 14 times more than FEMA maps suggest.Other Indianapolis neighborhoods that might have more properties at risk include those encompassing Washington Township, Driftwood Hills, Windcombe, Brightwood and Audubon Gardens.Marcus Saloane, a former president of the Friends and Neighbors Neighborhood Association, said in almost 30 years as a resident of the neighborhood he has never experienced flooding.&nbsp;However, if his neighborhood were to be hit by a 100-year flood, he imagines the effects could be "devastating," he said.&nbsp;With its report, the First Street Foundation also released an online tool called which allows users to input an address and evaluate the flood risk of that property.Measures to protect neighborhoods have been implemented in some parts of&nbsp;Indianapolis in recent years. Notably, &nbsp;near Butler University and North Capitol Avenue&nbsp;was completed last year to&nbsp;provide&nbsp;flood protection for households in the surrounding area.&nbsp;Clark Kirkman, who was&nbsp;president of the Butler Tarkington Neighborhood Association for the last stages of the flood wall's construction, estimated that&nbsp;couple hundred homes in the area were required to carry flood insurance at the time.&nbsp;The cost of flood insurance&nbsp;was a major reason behind neighborhood support for the project, he said.&nbsp;It was&nbsp;a heavy burden for some families, Kirkman said, and combined with the fact that property value is often diminished by flood risk, living in a floodplain can be expensive.&nbsp;Kirkman said he believes the city should be proactive in saving taxpayers and citizens these&nbsp;expenses, and he believes the flood wall is an example of the city&nbsp;doing so. He also&nbsp;acknowledges it's no&nbsp;small task.&nbsp;"City budgets are cash-strapped ... it often requires thinking outside the box in order to fund big projects like flood protection," Kirkman said. "It's very important because I think flooding events, they're only going to be going up."The flood wall near Butler-Tarkington was part of a $40 million Northside White River project, .Utilities:Lead, Legionella:Historically, people of color and people with low incomes are more likely to live in a floodplain, said Johnson, who does flood risk modeling&nbsp;for the state of Louisiana.This is partially because when it comes time for a community to protect a population from flooding by investing in a levy, dam or otherwise, the project has to prove the protection's&nbsp;benefits&nbsp;will outweigh the costs of building it. Because more affluent communities have higher property&nbsp;values, they are more likely to be protected by preventive floodplain investments, he&nbsp;said.Communities of color are also working against decades of marginalization in cities that compound their susceptibility to environmental events like flooding, said Elizabeth Browning, an environmental historian at Indiana University."When it comes to flooding, many communities of color do not have access to functioning sanitation infrastructure," Browning said.&nbsp;&nbsp;"In cities like Indianapolis, local government officials and public health departments have not historically devoted sufficient resources to shore up decaying sanitation systems, with excess rainfall and river overflows leading to significant public health problems."&nbsp;This cost-benefit analysis&nbsp;should be adjusted, Beik said. And in the face of a changing climate, he&nbsp;also said it's important for communities to start adopting resilience measures such as bolstering building standards, restricting construction in floodplains or in places that would&nbsp;worsen erosion&nbsp;and ensuring the floodplain maps are updated with modern data.Floodplain maps as they are now, Beik said, are the bare minimum&nbsp;required by FEMA&nbsp;— more comprehensive mapping may rely on cities or states&nbsp;taking the initiative.&nbsp;"It's not adequate to keep us safe.&nbsp;We need more than that, and that is on the shoulder of local communities," Beik said. "Climate is changing, things are changing, but what we can do is be smart about where we develop our land."Contact IndyStar reporter London Gibson at 317-419-1912&nbsp;or . Follow her on Twitter .&nbsp;Connect with IndyStar’s environmental reporters:&nbsp;Join&nbsp;.IndyStar's environmental reporting project is made possible through the generous support of the nonprofit Nina Mason Pulliam Charitable Trust.View Comments

Indianapolis StarView CommentsMore than 282,500 Indiana homes, businesses and other structures are at substantial risk of flooding, about 67&nbsp;percent more than the government currently estimates, That study calculates that 113,600 Indiana properties that are not&nbsp;currently in a mapped floodplain&nbsp;are at risk of flooding, representing an enormous potential cost to homeowners and the&nbsp;government alike.Many neighborhoods across the state, from Mishawaka and&nbsp;South Bend&nbsp;to Indianapolis&nbsp;are particularly vulnerable, according to the analysis.&nbsp;The problem,...

113,000 more properties may be at risk of flooding in Indiana than previously thought, report says

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