which stood above the high tide line, had whipped "back and forth during 

 the earthquake, but had not been damaged until that time. Another of 

 the floating houses rammed the city dock and tore the end off the dock. 



The Coast Guard Cutter Sedge was tied up at Cordova when the earth- 

 quake occurred. By 7:00 p.m. the ship was underway. However, at 8:19 

 it ran aground near North Rock Light , at a place with a depth of about 

 Us feet below MLLW, according to prequake sounding. Taking into account 

 the 13-foot draft of the ship, the 6-foot upheaval of the land, and the 

 tide level of one foot above MLLW, the drawdown must have been at least 

 25 feet. By 8:20 the ship floated free and returned to the harbor of 

 Cordova. The Sedge left Cordova again at the time of the highest wave 

 later in the night. In making good its escape it had to evade the same 

 floating house that had sheared off the end of the city dock. 



A fisherman who lived at Point Whitshed (Figure 200) reported that 

 the highest wave could be heard approaching on the northwest side of 

 Hawkins Island about 1 hour before it arrived (Chance, I968). It ap- 

 proached from Hawkins Cutoff and from Cordova simultaneously, and the 

 two waves met near the Point. The wave coming from Cordova appeared to 

 be about 25 feet high and was breaking all across the 3-mile wide Orca 

 Inlet. A rush of air was said to have preceded the wave (Chance, 1968). 



Water particle velocities associated with this wave were apparently 

 about 3O-UO knots. It is evident that the tsunamis had both a scouring 

 and silting effect on the sand sediments in the Orca Inlet. This is 

 indicated in Figure 203 where soundings taken in I963 and about 3 weeks 

 after the quake are compared. These soundings were taken by Reimnitz 

 and Marshall (1965) and the location of the profiles is shown in Figure 

 200. It is also to be noted that great change in bottom configuration 

 occurred during the 2-week interval between soundings taken by the U. S. 

 Coast and Geodetic Survey (a few days after the earthquake) and those by 

 Reimnitz and Marshall. These authors have compared pre- and postquake 

 soundings (u.S.C. & G.S.) to indicate where deposition has taken place 

 north of Cordova (Figure 20^+). 



Evidence of erosion is found in the fact that dead clams in patches 

 up to hundreds of feet in diameter littered the surface of the shoals . 

 The most common shell in these accumulations was that of the cockle, 

 Chinoaardium nuttalZi (Conrad), which lives just below the sediment sur- 

 face. Also present in large nijmbers were horse clam shells, Sahizothaerus 

 oapax, which lives normally at a depth of about 30 inches . The accumu- 

 lation of clams indicates that, in relatively large areas, the upper 30 

 inches or more of the seabed were planed off by strong currents . Strong 

 currents were also evidenced by the fact that the Coast Guard channel 

 buoys, moored with more than one ton of ballast, were moved for miles. 



Figure 205 is generally illustrative of the Cordova waterfront as 

 affected by the regional uplift from the earthquake. The damage sustained 

 at Cordova from wave action was estimated by the Anchorage Daily News of 

 April 18, 196U, to be $1,775,000 (see Table E-5 , Appendix E). There were 

 no casualties in this immediate area. 



Text resumes on page 319 

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