In this study area, the tidal ranges at four local tidal reference 

 stations (Cape Henry, Virginia Beach, False Cape, and Currituck Beach 

 Lighthouse) vary from 2.5 to 3.6 feet (0.8 to 1.1 meters) for mean 

 tidal range and 3.0 to 4.3 feet (0.9 to 1.3 meters) for spring tidal 

 range. Hampton Roads, Virginia, within Chesapeake Bay, is the nearest 

 National Ocean Survey (NOS) tide gage to the study beaches. Tides at 

 Cape Henry, Virginia Beach, False Cape, and Currituck Beach Lighthouse 

 are determined by applying tabulated corrections at these locations, 

 to those predicted at Hampton Roads. 



Mean and spring ranges, and mean tide levels tend to increase 

 as the distance from the influence of the Chesapeake Bay increases 

 (Table 3) . 



It is important to note that with this relatively low range, the 

 wind can have an important effect on the water level. It was observed 

 that with either strong onshore or strong offshore winds, the re- 

 sulting beach tide level remained either high or low, respectively, 

 throughout the 12-hour tidal cycle. 



2. Wave Climate . 



Wave climate data in this area have been summarized, synthesized, 

 and contrasted from six data sources by Gutman (1976) . These sources 

 include Marsden square ship wave observations for Marsden 1° subsquare 

 65 of Marsden square 116 (1948 to 1973) and Chesapeake light observa- 

 tions on the shelf, Virginia Beach gage (1964-1969), Cooperative Surf 

 Observations Programs (COSOP) , and VIMS-CERC wave observers at the 

 shoreline, and Sverdrup-Munk-Bretschneider (SMB) hindcast data for 

 1948-1950 by Saville (1954). 



Percent frequency occurrence of significant wave heights for all 

 these sources, and monthly averages of significant wave heights and 

 periods for the Virginia Beach gage (located at Profile line 3) are 

 shown in Figures 7, 8, and 9. Ship wave observations by direction 

 and height are shown in Figure 10 (Gutman, 1976). These data show 

 that: 



(a) The highest shoreline waves (> 2.3 meters) occur only 0.1 

 percent of the time (COSOP data) . 



(b) the highest average significant waves occur in October, 

 February, September, January, March, and April (in order of 

 decreasing heights), and range between 0.9 and 0.6 



meter. The lowest heights occur May to August. 



37 



