Explanation
Background: This ordinance authorizes the Director of Public Utilities to enter into a cooperative agreement with the U. S. Geological Survey, United States Department of Interior, for Scioto River Flood Inundation Mapping services for the Division of Water Reclamation. The contract amount is $224,000.00, with a contingency of $17,000.00, for a total of $241,000.00 being authorized by this ordinance.
Over its history, the City of Columbus has experienced substantial and widespread damage from flooding by the Scioto River. The Scioto River has experienced severe floods numerous times, notably in March of 1913, January of 1959, and January of 2005.
Limited tools exist to help Columbus floodplain managers and emergency responders prepare for and respond to floods. The Federal Emergency Management Agency (FEMA) provides Flood Insurance Rate Maps that show the limits of floods with a particular likelihood of recurring, specifically floods having a 1% chance in any given year or 0.2% chance of recurring in any given year (aka 100-yr and 500-yr floods). However, these maps do not give the picture of what land is expected to be inundated during flood events that don’t exactly match the severity of these floods.
The National Weather Service provides 48-hour predictions of flood stage at a U.S. Geological Survey stream gage on the Scioto River south of Frank Rd. This provides the recorded and predicted depth of flooding at that location; however, there is no information readily available that would translate that information into a prediction of what areas are expected to flood.
The agreement will provide surveys and develop simulated river models that will be used to develop digital flood maps that show the areas that would be inundated at different river stages (maps for 11-15 different stages will be produced). An online tool hosted by the U.S. Geological Survey will allow anyone with internet access to view the tool to better understand the fl...
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