Lessons Learned: The floods of ’18

Local News

DES MOINES – Last year, hundreds of houses had basements full of water across the city of Des Moines. The biggest project to come out of the 2018 floods is the new sewer project. Local 5 got a special tour with the city’s Public Works Department on how it’s all going to fit together. 

Des Moines Public Works Director Jonathan Gano took Local 5 to four high priority sites in the city. The one called “the big one” has been on the to-do list for a while. 

“What’s traditionally been happening for the last two decades is this intersection will fill up and as soon as you get a foot or two of water in the intersection, it starts making its way into people’s basements. And then it just keeps going until you’ve got 8-feet of water up to the rafters, in at least 10 homes on this block here,” says Jonathan Gano with Public Works. 

In the 2018 storm, about 60 homes in the Beaverdale neighborhood had major water damage. Many qualified for the buyout, but that would leave a lot of empty space. City engineers came up with a different plan.

“Bury concrete boxes that will take up the entirety of the street underneath the street and bury them under the ground. So that the flash of water that’s waiting for storm sewer to catch up in capacity…has a place to wait… other than people’s basements.”

It’ll take about a year to complete, and it will be invasive for the people who live there. But Gano hopes it will do the trick to keep water out of these homes.

A site where you can see construction right now is here at 38th and Amick. It was completely flooded on June 30 of last year. Water came through a ravine, crossed the road, and smashed the embankment caving it into the creek bed below.

Neighbors here were largely lucky with not much property loss.

Gano says the damage was obvious and easy to see which means this site didn’t need a redesign, but just a simple repair. “The pipes that are carrying the regular every day every other week rain stores are the same ones and they are still doing their job. What we wanted to do was put this back and make it safe and restore its capacity to do the function it was built to serve.”

However, a stone’s throw away on Urbandale and 35th, a completely different challenge. 

Two houses once stood on a now empty lot with a storm drain pipe in the back of the property. Floodwater overwhelmed that pipe and flowed right through the homes. 

In an instance where more construction didn’t make sense, the city took a simpler approach to give floodwater space. They bought and tore down those two homes. “This approach is sometimes the cheapest way to solve the problem, for a couple thousand dollars, we can erase the homes and get them out of the way for future flood waters. Whereas building a pipe from there to across the street could easily be one $1-2 million.

Nowhere were buyouts more widespread than along 4 Mile Creek. The area has been vulnerable for decades with homes flooded and water rescues in the raging creek. 

The tree-lined streets are in the 100 and 500 year flood plains. A year ago, they were also lined by houses. 100 of them were so badly damaged they were eligible for the buyout. 80 families accepted and the city went in to clear the space.

“So we can take this land and turn it back to flood plain and just let the creek do what it does. Low density single family neighborhood hard to justify the investment to fed govt for levees and flood control. So often times the best way to protect a neighborhood is to pull back the boundaries to where we know its safe and everyone can live with a reasonable amount of security and resiliency.”
 
There are some holdouts, but for the most part, it’s quiet here after the storm. Gano knows this isn’t the last of the work to be done, nor is it the final test from mother nature. “What we’ve seen over the last several years is an increasing intensity of rainfall. More frequent and more intense than in earlier decades or the last century. So we are expecting things to get worse before they get better.”

Local 5 is committed to holding local officials accountable for what they’ve learned from last year’s devastating floods. That’s why we’re looking back at the floods of 2018 with a We Are Iowa Original Documentary. You can watch it next Sunday on weareiowa.com. We will be hearing stories from Stephanie Angelson, Jacob Peklo and our team of Local 5 photojournalists. 

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