between 4-see and 8-sec waves than between 8-sec and 12-sec 
waves. 
1. 
Changes in refracted wave properties increase with the dredged 
hole depth. The dependence of the changes on dredged depth is 
similar to the dependence of changes on wave period, i.e., the 
change is larger for relatively small dredged depths and there- 
after only gradually grows with increases in depth. 
76. Discussion. Several hypothetical dredged bottom configurations 
were examined in this task. For the northern site, the plans with sediment 
dredging below 6 ft produced notable changes in refraction for waves of 
periods greater than about 8 sec. However, these plans also contained more 
beach fill volume than is necessary for the initial proposed beach fill. A 
smaller dredging area (for a given depth of sediment dredging) would have a 
less pronounced effect on the nearshore wave pattern. Also, dredging beyond a 
specified water depth at the deeper contours of the site or seaward of the 
site would mitigate the influence of the altered bottom topography on the 
waves. 
77. The present study has indicated that random dredging in the shal- 
lower portions of the northern borrow site may have an impact on the shore- 
line. The natural infill sediment transport rate by waves and currents is 
expected to gradually fill and smooth the borrow pit, reducing influence of 
the hole with time. 
48 
