The recording depth gage is intended to supply beach profile data 

 from that segment of the profile near the surf zone where it is hazar- 

 dous to make a fathometer survey or to anchor the boat for a lead line 

 sounding. Deployment of the depth gage involved traversing the range 

 line quickly to a station very near the break point and then dropping 

 the sensing package as a sextant angle is shot at the station. After the 

 recording period the sensing package is quickly recovered by the boat 

 and the measurement is read. The instrument was employed in field usage 

 a number of times during its development, and was found to yield measure- 

 ments that were inconsistent with independent lead line measurements. 

 Each field trial brought further modification of the instrument design. 

 As a result, all field information obtained from the instrument during 

 this study has been used for calibration purposes and is reported in 

 Appendix C. 



5 . Visual Wave Observations . 



Wave energy incident to the study-site beach was documented by two 

 methods: (a) visual wave observations made daily on weekdays at South 

 Range; and (b) wave measurements made with a line array of pressure sen- 

 sors located at a depth of -35 feet (-10 meters) on South Range. Visual 

 observations were made using the same procedure as developed for the CERC 

 Beach Evaluation Program. Wave and surf observations made at the beach 

 level at South Range included an estimate of the height of the highest 

 one-third of the waves, the average period of 10 consecutive waves, and 

 the breaker type. 



To supplement the visual wave observations at the beach level, 

 additional wave observations were made from a fixed point at the top of 

 a 300-foot (91 meters) high sea cliff at South Range. From this point 

 a visual estimate of the breaker angle and a photograph of the wave con- 

 ditions were made. The photograph was always oriented so that its bottom 

 margin was aligned with the beach in order to accurately illustrate the 

 breaker angle. Appendix D is a tabulation of the daily visual wave 

 observations from June 1972 through May 1974. 



Wave measurements from the pressure sensor array are described in 

 a separate report to CERC including the conclusions of that study. 

 Appendix E is a comparison between the visual observations and the pres- 

 sure sensor array measurements for those dates with synoptic data. This 

 comparison indicates that the visual observations and pressure sensor 

 measurements are in general agreement for wave direction when wave refrac- 

 tion from the sensor array to the beach is taken into account. 



IV. DATA REDUCTION PROCEDURE 



All measurements of beach profiles for this study were determined 

 from the permanent bench marks established on the beach. Distances were 

 referenced seaward from the bench mark and elevations were referenced to 

 mean sea level (MSL) . The mean lower low water (MLLW) datum is -2.7 feet 



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