Storm Surge Flooding at the US Naval Academy

 

(requires Google Earth or another KML viewer)

 

New: Melissa, October 2019

 

This analysis uses a Lidar Digital Elevation model, and the MICRODEM computer program to produce a KML file you can view in Google Earth.  You can see the predicted flooding at a number of water levels, referenced to NAVD of 1988.  We also have historic shorelines depicted by the Maryland Geological Survey; perhaps not surprisingly, almost all the area that floods is fill emplaced after the founding the Naval Academy in 1845.

 

You can see the current tides and refer them to both NAVD and MLLW, as well as several other vertical datums, in either feet or meters.

 

You can compare the observations with the NOAA prediction.  Insure that you understand the tidal datum used in the model, the units (feet or meters), and then determine the matching  NAVD1988 level.

Hurricane pages

 

 

Water level in downtown Annapolis and the Naval Academy from a storm such as Hurricane Isabel, overlaid on a 1 m resolution LIDAR DEM.

Water levels go from 0.2 m to 2.5 m in 0.1 m steps. This requires that the point be below the water level, and that it have a clear path to the bay.  This will be fooled if water can come through the seawall or a storm drain, for instance, but provides a reasonable estimate.  It will also have challenges in areas where there has been substantial recent construction, such as around Rickover and Hopper Halls, which at one point provided a major entry point for flooding waters.

There are many caveats to this analysis, and there is no claim that it accurately portrays what happened in Isabel or would happen in a future storm.

This is a low resolution depiction for web delivery, and does not do justice to the quality of the DEM data.  You cannot stop it or change the playback speed.  You can get much more control over the visualization with the KML model for storm surge in Annapolis created by MICRODEM.

Actual water levels for recent hurricanes and flooding events that I monitored and in some cases waded through:


"All time*" worst flooding events at Annapolis

Date Time Max Feet above MLLW Hours above 4 ft MLLW Storm
24-Aug-33 2:00 AM 6.181 16 1933 Chesapeake-Potomac Hurricane
16-Oct-54 4:00 AM 4.583 7 Hazel
13-Aug-55 12:00 PM 4.583 7 Connie
8-Mar-62 11:00 AM 4.281 4  
6-Sep-79 9:00 AM 4.541 6 David
5-Nov-85 3:00 AM 4.521 7 Juan
7-Sep-96 3:00 AM 4.822 14 Fran
19-Sep-03 12:00 PM 7.195 18 Isabel
1-Oct-10 1:00 AM 4.222 4 Nicole
17-Apr-11 7:00 AM 4.062 3  
4-Oct-14 6:00 AM 4.094 2  
10/12/2019   4.15   Melissa
 

* History starts with the tide gauge in 1929, so the record extends less than 100 years.  Compilation by Davies and Guth

 


last revision 10/15/2019