Ohio's Coastal Erosion Area Program
How to Read and Use
Finalized 2010 CEA Maps
Online and printed (paper) 2010 CEA maps are the same, with identical map frame numbers and explanation keys. To read both printed and downloaded maps, you will need at hand the 11- x 17-inch map(s) and corresponding data table(s). PDF maps downloaded from the Internet mapping service (IMS) include the data tables as part of the file. Printed map books have all data tables in a separate booklet at each map viewing location.
Note: If you are using a downloaded PDF map from the internet, SKIP to Step 3.
Step 1: Using the Index Map
The first map in the map book is the Index Map; use it to find the correct map frame for the property of interest. On the Index Map, small, numbered rectangles cover the coast. The rectangles represent individual map frames. These map frames may overlap, perhaps multiple times (for example, the Lake Erie islands). As a result, the property of interest may be represented in more than one map frame. Select the map frame where the property of interest is most centrally located, and make note of the map frame number.
Step 2: Finding the Map Frame Number of Interest
In the map book, find the map frame number of interest. Each map frame number represents an individual CEA map found in the map books. Each CEA map has a title block that lists the county name and the frame number. For example:
Coastal County
Frame: 100
If the map frame number on the index map is "Coastal County 100," turn to map frame 100 in that map book. The frames are arranged in east-to-west geographic sequence in the map book. Some map frames are too large for a single sheet and overlap two pages.
Step 3: Finding the Property of Interest
Find the property of interest on the map frame by looking for familiar landmarks, such as intersections, rooftops or other recognizable features.
Step 4: Understanding the Map Symbols
Use the legend, titled “Explanation,” on each map frame to understand the map symbols.
- The dashed line ("Recession Line 1990") marks the location of the crest of the bluff, bank or dune in 1990.
- The line of crosses ("Base (2004) Recession Line") indicates the location of the crest of the bluff, bank or dune at the time of the photograph (April 2004).
- The red line ("Landward extent of CEA") denotes the landward edge of a coastal erosion area (see Step 5 below).
- The black lines ("Transects") identify locations on the map. Each transect has a unique number. For example, on Frame 100 the transects would be numbered 100-1, 100-2, and so on, generally from east to west, except on the islands. If you contact ODNR with questions about a property, please note the number(s) of the nearest transect(s) so we can find it quickly.
Step 5: Determine if the Property is in a CEA
Determine if the property of interest lies in a coastal erosion area by looking for the red 2010 CEA line. If this line crosses a portion of the property, or if the property is between the line and the lake, then part or all of the property lies within a coastal erosion area.
Step 6: Using the Data Tables
After examining the map, see the data table for the map frame of interest (see Data Table example). Data tables are arranged according to map frame number. For example, for map frame "100" in "Coastal County," turn to the data table marked "Frame: ANY100." (Data tables are arranged in the booklet in numerical order.) Find the previously identified transect number(s) on the data table. The columns are explained below:
- The column MEAS DIST shows the measured erosion distance at each transect. This is the amount of erosion, in feet, at each transect from 1990 to 2004.
- The RECESS RATE column indicates the average rate of recession (that is, erosion) at each transect from 1990 to 2004.
- The ANTICIPATED DIST column indicates the expected amount of erosion at each transect for the next 30 years if no additional erosion control measures are put in place. This is always measured from the top of the bluff or dune crest.
- The STATUS column indicates whether a particular transect is located within a coastal erosion area. For each transect, the entry in the STATUS column will be either "CEA" or "NO CEA."
Note: The actual landward extent of a coastal erosion area is always measured from where the bluff or dune crest currently sits, not necessarily from where the bluff or dune crest is shown on the map. Some rapidly eroding areas may have receded appreciably since the aerial photographs were taken. You should use the ANTICIPATED DIST column and measure from the current position of the bluff or dune crest to determine the actual landward extent of a coastal erosion area.
Background Information on CEA Mapping
To date, two editions of CEA maps and data have been issued. Some public viewing locations may still have copies of the final 1998 CEA maps and data (with blue covers and black-and-white maps), but these are no longer in effect for regulatory purposes. The finalized 2010 CEA maps and data supersede all previous editions. They are viewable online or in hardcopy at local agencies.
For local agency locations with printed paper maps, CLICK HERE, or, download a list of ALL locations as a single PDF file.
For how to read the CEA maps, CLICK HERE.
For additional information on Ohio’s CEA Program and what a CEA designation means for a property, please download the fact sheet 2010 Mapping of Ohio’s Coastal Erosion Areas.
If you have questions about interpreting the final 2010 coastal erosion area maps, please contact the ODNR Division of Geological Survey at 614.265.6576.
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