BEACH EROSION STUDIi 



Beach erosion control studies of specific localities are usually made 

 by the Corps of Engineers in cooperation with appropriate agencies of the 

 various States by authority of Section 2 of the River and Harbor Act approved 

 3 July 1930. By executive ruling the costs of these studies are divided 

 equally between the United States and the cooperating agencies. Information 

 concerning the initiation of a cooperative study may be obtained from any 

 District or Division Engineer of the Corps of Engineers. After a report on 

 a cooperative study has been transmitted to Congress, a summary thereof is 

 included in the next issue of this bulletin. A summary of reports transmitted 

 to Congress since the last issue of the Bulletin and a list of authorized 

 cooperative studies follow: 



SUMMARIES OF REPORTS TRANSMITTED TO CONGRESS 



GULF SHORE OF GALVESTON ISLAND, TEXAS 



The area studied is located on the Gulf shore of Galveston Island, 

 Texas, about 3U5 miles west of the mouth of the Mississippi River. It ex- 

 tends southwest from the south jetty at the entrance to Galveston Harbor a 

 distance of 11.5 miles. Galveston Island is a low barrier beach island of 

 fine sand about 28 miles long and varying in width from 1/2 to 3 miles. 

 The natural surface of the island has a general elevation of J4 to 5 feet 

 above mean sea level. Dunes along the Gulf shore have top elevations up 

 to 12 feet above sea level. The foreshore and offshore bottom are gently 

 sloping. 



Galveston is a summer resort community and an important Gulf port. 

 The population of the island is estimated at 80,000. In addition, it is 



estimated that there are as many as 7^0,000 summer visitors. 



The mean tidal range in the Gulf at Galveston is 1.3 feet. Tidal 

 heights are greatly influenced by winds and storms, the maximum tidal 

 height of record being lit. 5 feet above mean sea level. Tides over 3 feet 

 in height however are relatively rare, having occurred on the average about 

 once in 2 years. Jith light winds and normal tides, waves just offshore in 

 the study area probably do not exceed 2 feet in height. Available data 

 indicate that during hurricanes with accompanying high tides, wave crests 

 have reached elevations of about 20 feet above mean sea level. Swells from 

 the east occurring 10 percent of the time, are refracted to approach normal 

 to the shore between the jetty and the center of the groin area, but west 

 of that point they have a westward component. Swells from the south occur 

 8 percent of the time and have an eastward component. 



In its natural state the shore of the study area was subject to erosion, 

 at least in the portion adjacent to the inlet to Galveston Bay. Following 

 construction of the Galveston south jetty from 188? to 1897 , extensive 

 accretion occurred in the section for about 3.6 miles southwest of the jetty. 



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