Flood Maps and Data for the City of Athens

 Current Mapping

The official maps and flood studies used for regulatory purposes by the City of Athens are:        

1) "Flood Insurance Study, City of Athens, Ohio, Athens County" (FEMA, Federal Insurance Administration, September, 1979).

2) "Flood Boundary and Floodway Map" and "Flood Insurance Rate Map" (both dated March 28, 1980)

3)  "AFFRI (Appalachian Flood Risk Reduction Initiative) Flood Risk Study", (Ohio Department of Natural Resources, Division of Water, Floodplain Management Program, February, 2004) and

4)  "AFFRI Flood Map" (Ohio Department of Natural Resources, Division of Water, Floodplain Management Program, September 29, 2003.) 

The floodway, 100- and 500-year floodplains are delineated on the City of Athens Flood Insurance Rate Map, which can be found through the FEMA Map Service Center.  Copies of all maps and flood studies are located in the Mayor's office in the City Building, 8 E. Washington, Athens, OH  45701.

Athens County is in the 90-day appeals period of the Ohio Map Modernization project.  See Recent and Upcoming Events for more detail.  Preliminary maps were released on Dec 11, 2008.  Athens County has 90 days from Dec 11, 2008 to inform FEMA of any corrections needed on the new digital maps.  After 90 days, a "Letter of Final Determination" (LFD) will be issued, and the city will have 6 months to update its regulations to reflect the new maps.  The maps are located in the Mayor's office in the City Building, 8 E. Washington, Athens, OH  45701, and may be viewed by any person wishing to do so.  The map panels can also be found on the City Planner's webpage as .pdf files.  The main City of Athens panel is copied below.

 Historical Data

The largest flood known to affect the City of Athens occured in March, 1907.  The peak discharge of this flood (also called volumetric flow) was estimate to be 50,000 cubic feet per second (cfs.) 

There has not been any major flooding within the City of Athens since 1968.  The 1960's was a decade of high peak discharges in the Hocking River.   

Table 1:  Peak Hocking River discharges in the 1960's

The major flooding resulting from such large discharges provided impetus for a structural floodplain management change.  In 1970-71, the US Army Corps of Engineering (US ACE) re-channelized the Hocking River.  This structural project widened and deepened the Hocking River as it flows through the City of Athens.  The project was designed to provide protection to the City of Athens from flooding for river discharges of under approximately 32000 cfs.  Since the re-channelization, there have not been any high discharge events.  The highest recent events are listed in Table 2.

Table 2:  Recent peak Hocking River discharges

These events caused minor to moderate flooding within the city.  The re-channelization project has never been tested with a high discharge event. 

The National Weather Services Advanced Hydrological Prediction Service contains historical crests and flood impacts for the City of Athens.  The United States Geological Survey (USGS) provides real-time data for rivers in the U.S.  Their Hocking River Real-Time Data webpage gives new data approximately every 4 hours.  Data provided are the gage height of the water in the Hocking River, and the discharge, or amount of water flowing in the river, in cubic feet per second.