OLATHE, Kan. —Stormwater experts in Johnson County will soon be using new tools to study flooding along Indian Creek.
On Thursday the Board of County Commissioners (BOCC) approved a $875,200 grant from the Federal Emergency Management Agency (FEMA) for floodplain mapping.
Sarah Smith, project manager for Johnson County Stormwater Management, said funds from the FEMA grant will go toward creating a 2-D floodplain model and map project for Indian Creek.
“Our existing one dimensional modeling has been and continues to serve as a great planning tool. However they are based on data that is now 20 years old,” Smith said.
“We have 20 more years of gauge data that has been recorded. We have had changes in terrain and also significant advances in computer and software technologies that can now be used.”
Indian Creek was selected for the modeling because it frequently experiences flooding during heavy rain events.
Smith said compared to the current modeling system, the two dimensional models can better show how water flows throughout the watershed and how certain areas could react during a flood event.
In addition to providing a more clear model of the creek, Smith said the project will also provide three additional features that could benefit the county.
The project will include a probabilistic flood risk assessment. That analysis would help estimate the frequency of flooding hazards and show ways to potentially avoid future losses.
Smith says 2-D mapping could help identify and define the county’s mitigation needs throughout the watershed.
The project would also help stormwater experts calculate future precipitation conditions that can serve as a planning tool for communities located near Indian Creek.
The project will cost roughly $1 million to complete. It will be paid for through the FEMA grant and $154,440 in stormwater management funds approved by the commission last October.
Smith estimates the new 2-D model of Indian Creek will be complete by November of 2022 and the three additional features will likely be complete by February of 2023.