A Silver Jackets pilot project on Wildcat Creek in and near the City of Manhattan, Kansas, demonstrates the advantages of leveraging resources and collaborating on a shared vision for a flood risk management solution. Wildcat Creek had severe flooding in 2007, 2010, and again in June 2011. The 2011 event resulted in the evacuation of over 200 people. Future flooding in the 100 square mile watershed is inevitable and could get worse unless mitigation action occurs.
With recent flooding fresh in the public’s mind, there was a window of opportunity available to promote flood risk management planning. In support of the multiagency need to communicate the flood risks and address the problem, the Kansas Hazard Mitigation Team was awarded Silver Jackets Pilot Project funds for a new flood warning system and flood inundation maps for the area to enable public understanding of flood risks. For Wildcat Creek, the National Weather Service (NWS) Advance Hydrologic Prediction Service (AHPS) was used to produce web-based inundation maps that depict the extent and depth of floodwater in the vicinity of a NWS forecast location. This allows users to visualize flooded areas for river levels ranging from minor flooding through the largest observed flood of record. Flood categories follow the commonly used color coding for increasing severity, similar to radar intensities.
A team effort, including the Kansas Division of Water Resources, U.S. Geological Survey, Federal Emergency Management Agency, National Weather Service and U.S. Army Corps of Engineers, was required to produce these three dimensional flood inundation maps.
In conjunction with the mapping, a strategic master plan or Floodplain Management Plan (FMP) (pdf, 79 MB) for managing flood risks in the Wildcat Creek watershed was written. The plan documents the flood risks and committee decisions on managing flood risks while establishing action items for future mitigation efforts. The FMP meets the requirements to be eligible for both USACE construction funds, as well as reduced rates for National Flood Insurance Program premiums through the Community Rating System. The success of this FMP is largely due to engaging the public immediately following the flood event.