The completed model running at the equivalent of the flood expected once in 100 years (the red line). For reference, the blue line is the equivalent of the Summer 2017 flood.

Testing the waters: experts find solutions to Indian Creek flooding

A physical model was built because computer models did not reflect what was happening in real life.

By Jill Draper

After pumping more than 200 gallons of water across a room-sized model of Indian Creek, engineers have pinpointed three areas contributing to flooding along 103rd Street in south Kansas City.

“What we’ve found in doing these models over the years is that there’s always an aha! moment—something we didn’t expect,” says Don Baker, owner of Water Resources Solutions, which managed the construction of a 25 by 70-foot foam model. 

Baker’s firm worked with KC Water Services and the Army Corps of Engineers to study the 103rd Street area, mostly between State Line and Wornall roads. The goal was to test potential solutions after two huge rainfalls in July and August of 2017 caused major damage to homes and businesses and led to the demolition of a strip mall where Coach’s Bar and Grill operated.

A downpour on May 31 created some flooding along Indian Creek’s banks at 103rd and Wornall. Photo by Bill Rankin

A physical model was built because computer models did not reflect what was happening in real life, notes Baker, who says while the floods five years ago were the highest on record, a 100-year flood event is still to come. “The floods in 2017 were 25-year and 50-year events. Surprisingly it hasn’t been worse before.”

A worse future may be avoided if officials address those three aha! situations shown by the model, says Baker. One concerns a spot where a stone ledge propels the creek into a right-angled turn north of Ultra Clean Car Wash and east of Cosentino’s Price Chopper. By dropping paper chads into the water as it streamed through the flood model, researchers discovered the chads began to swirl in a vortex at this point and travel upstream against the current.

The model running at the 1-in-100-year flood, looking upstream, from roughly the Center Middle School tennis courts. This is an illustration of the vortex just to the east of Watt’s Mill Plaza. You can see that when Senior Hydraulic Engineer Dr. Jerry Richardson adds red dye to the water, you can see a portion of the flowing water strikes the bedrock there and actually turns and flows back upstream, toward State Line Road. (In case you wonder, the push broom is used to simulate the presence of trees and heavy brush along the banks, which also influences how and where the water flows.)

A solution for this problem is to construct rock dikes perpendicular to the shore to lessen the severity of the curve and keep the water flowing in the same direction, says Baker.

A second aha! moment documented how floodwater jumped the creek and traveled behind the QuikTrip at 10232 Wornall Rd. and past Valvoline Instant Oil Change before crossing Wornall and circling around Dunkin’ Donuts on the other side. Then it returned to the creek bed. A solution that worked in the model was to enlarge the opening of the bridge where Wornall crosses the creek.

According to Baker, he and other engineers were not exactly surprised by this fix (Telegraph readers, in fact, have made the same observation), “but it was very gratifying to see that in the model.” 

This is an example of the ability to quickly test alternative engineering design solutions. The green area represents the additional capacity that could be added by extending the Wornall Road bridge. Running the model at high flow, recording the flood patterns, then removing that portion of the model and running the model again at the same flow lets us quickly see whether it makes a difference in flooding nearby. (In this case, it appeared to.)

Floodwater again jumps the creek bed in Kansas just west of State Line Road for the model’s third aha! It travels north along 104th Terrace past Gates Bar-B-Q and along State Line before running east onto 103rd Street. The situation is complicated by a small tributary that flows into the creek on the Leawood side.

What’s the solution for this situation? “That’s a good question,” Baker says, noting that Leawood officials are thinking about building a similar flood model from State Line to Mission Road for further study. It’s also possible that downstream improvements on the Missouri side will improve the flow of Indian Creek enough to help, he says.

What happens now? FEMA (the Federal Emergency Management Agency) is partnering with KCMO and Johnson County, Kansas to develop more accurate flood plain maps along Indian Creek, Baker says, adding the process might take five years and would include a public review. “People’s flood insurance rates could change,” he says. “There’s still a lot of pressure in this area to redevelop it.”

Baker says the $400,000 foam model (which sits in a KC Water maintenance building downtown) was “flooded” for research and demonstrations nearly 20 times in the last two years for the Corps of Engineers, City Council, other metro area city officials, school groups and Engineers Week. A public open house was planned by KC Water before the pandemic, but it’s unclear when that event might happen.

It’s also unclear what action steps the city will take to fix Indian Creek. But when they do, the cost savings should be phenomenal, according to Mike Smith, who works with Baker as director of marketing for Water Resources Solutions. 

Indian Creek has the same basic problems as the Country Club Plaza’s Brush Creek, which was “cleared out and channelized at a cost of billions in today’s dollars,” he says. “It was what we knew at the time. Now we can do much more focused solutions.”






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