cast into the water immediately landward of the breaker zone in line with 

 two or more of the marker stakes. The distance traveled by the ball in 

 a 50-second period was measured. This process was repeated about 5 to 

 10 times. In the summer period, winds were sufficiently weak so that 

 the ball's travel was unaffected by the wind. In the winter period, 

 winds were of sufficient velocity frequently enough to require a dif- 

 ferent technique and the ball was replaced by a balloon filled with 

 freshwater. 



The presence of rip currents and runnel currents may cause problems 

 in measurement as these currents often flow in a different direction 

 than the dominant drift pattern or they may represent extremely localized 

 energy conditions; therefore, they may not accurately reflect the dominant 

 longshore currents operating over a large area. 



The sum of longshore current velocity measurements for the summer 

 period was -13.8 centimeters per second with extremes of -84.2 and +33 

 centimeters per second. In the winter period, extremes of -93.7 and +64 

 centimeters per second were recorded; the sum of the winter readings was 

 +1.2 centimeters per second. 



3. Ground Water Elevation . 



The elevation of the ground water surface above MLW was measured 

 hourly during the summer period. Subfreezing winter temperatures pre- 

 vented measurement during the winter study. A 5-meter section of 1.5- 

 inch pipe with a well point attached to one end was driven into the 

 incipient berm to a depth of about 4.5 meters using a sling and hammer- 

 type drilling rig. The elevation of the top of the pipe was tied in to 

 MLW. Measurements were made from the top of the pipe to the water 

 surface by using an aluminum dipstick streaked with carpenter's chalk. 

 Readings ranged from 242 to 348 centimeters above MLW depending upon 

 the amount of precipitation and the tidal stage. 



4. Meteorological Parameters . 



a. Windspeed and Direction . Windspeed and direction were measured 

 with a Taylor Windscope three-cup anemometer and wind-direction indicator. 

 The instruments were mounted on a 15- foot pole placed at the crest of 

 the foredune ridge adjacent to the instrument shelter. Windspeed and 

 wind-direction measurements were taken every 2 hours by recording eight 

 readings, spaced 10 to 15 seconds apart. A sealed potentiometer, 

 coupled with a weather vane mounted opposite to the anemometer, gave 

 wind-direction readings over a 360° range. 



By using the sine of the wind direction, measured as an azimuth, it 

 is possible to determine onshore and offshore components of the wind 

 data (Fox and Davis, 1971). The shoreline of the study area trends 350°, 

 so that wind azimuths between 350° and 170° are classified as onshore 

 winds and wind azimuths between 170° and 350° as offshore winds. 



