The seasonal cycles in the beach profiles shown by the empirical eigen- 
function analysis and the closely spaced profile lines have implications for 
beach-fill operations and the location of feeder beaches. Though net transport 
is toward the south, south of profile line 24, this region may be the site of 
a local transport node with the net drift north of this region toward the north. 
A feeder beach located north of the node would not supply sand to the southern 
beaches. Sand dredged from Barnegat Inlet during the summer of 1979 and placed 
on the beaches in the vicinity of profile line 3 was probably transported north- 
ward or offshore where it reentered the inlet system rather than nourished the 
southern beaches. Other nodal points, either temporary or permanent, may 
exist along the island. Predicting their location is, at present, not possible. 
Closely spaced profile lines placed within groin cells would be necessary to 
determine their position and motion. Studies on the effectiveness of the beach 
fill and its direction of transport are being conducted (Ashley, Halsey, and 
Farrell, 1980). 
The profile envelopes (App. E) show that the sweep zones of the beach pro- 
files have been considerable over the period of study. Variations of as much 
as 4 meters are not unusual in the region of the MSL intercept. This vertical 
excursion of the profile must be taken into account in the design of pipelines, 
coastal structures, and other protection measures. 
Limitations in the amount of information obtainable from the Long Beach 
Island data set may be overcome in future studies by alterations in the sam- 
pling design which take into account the beach structures, offshore topography, 
nearshore below MSL changes,-. waves, currents and the anticipated methods of 
data analysis. The closely spaced profile line studies show that beach changes 
within a groin cell cannot be determined with fewer than three profile lines 
per cell. Comparative analysis may be done with this data set and that from 
Westhampton, New York (DeWall, 1979) to provide additional insight into the 
dynamics of groin cells. The distribution of profile line measurements depends 
upon the scale of the processes under consideration and may require that pilot 
studies be carried out for at least one season before the final design is 
adopted. It is likely that each beach environment will require a somewhat dif- 
ferent approach. The offshore topography must be considered when laying out 
the profile lines. The linear shoals off of Long Beach Island certainly affect 
the distribution of sand transport by causing differential wave refraction. 
Profile lines should be extended farther offshore than the -2-foot MSL position 
as was done in this study. The depth of measurement depends upon the wave 
regime, currents, expected depth of sediment movement and the resources of the 
measurement team, but should extend beyond the breaker zone. The spacing and 
timing of profile line measurement again depend upon the scales of the pro- 
cesses but also on the expected method of analysis. Statistical methods includ- 
ing eigenfunction analysis work best when data are evenly distributed in time 
and space. Sets of closely spaced profile lines laid out in selected groin 
fields along the island would have been appropriate for Long Beach Island. The 
frequency of surveys depends upon the expected total length of the time series 
and the resources available. Monitoring studies should last several years to 
obtain adequate statistics of seasonal variability with surveys taken each month 
for longer studies and twice each month for short studies. Beach changes during 
storms are highly nonlinear and can be extreme in a short amount of time. 
These events should be monitored individually. Wave information is best ob- 
tained by a reliable gage giving height and direction. Adequate devices are 
‘generally not available or are very expensive. Well-trained observers 
of 
