generated and rechecked. When the validity of the data had been confirmed, 

 monthly tabulations of daily highs and lows, hourly heights (instantaneous 

 height selected on the hour) , and various extreme and/or mean water level sta- 

 tistics were computed. The monthly or annual mean sea level (msl) reported is 

 the average of the hourly heights, while the mean tide level is midway between 

 mean high water and mean low water which are the averages of the daily high 

 and low water levels, respectively. 



Visual Observations 



48. Daily visual observations were made near 0700 hr to supplement in- 

 strumented data collection. These included observations of surface current 

 speed and direction at (a) the seaward end of the pier, (b) the midsurf posi- 

 tion on the pier, and (c) the beach 500 m updrift of the pier. Surface cur- 

 rents were determined by observing the movement of dye on the water surface. 



49. Also measured were wave approach angles at the seaward end of the 

 pier, breaker angle, and breaker type nearshore. Wave direction was also 

 determined using a Raytheon Mariner's Pathfinder radar, manufactured by the 

 Raytheon Marine Company, Manchester, N. H., mounted on the roof of the FRF 

 building; use of this system for measuring ocean waves is explained by Mattie 

 and Harris (1978). 



Bathymetric and Pier Surveys 



Collection 



50. Profiles were obtained monthly and after storms by using the 

 Coastal Research Amphibious Buggy (CRAB), a 10.7-m-tall amphibious tripod, and 

 a Zeiss Elta-2 total station surveying system described by Birkemeier and 

 Mason (1984). Each profile extended seaward from the baseline behind the dune 

 to a water depth of about 10 m, within 0.6 km north and south of the FRF pier. 

 Their locations are shown in Figure CI. The survey accuracy was about ±3 cm 

 horizontally and vertically. Monthly soundings along both sides of the FRF 

 pier were also collected by lowering a weighted measuring tape to the bottom 

 and recording the distance below the pier deck. Soundings were taken midway 

 between the pier pilings to minimize errors caused by scour near the pilings. 



26 



