101. The existing project was adopted in 1922, providing a 7,500-ft 

 jetty on the northern side of the mouth by extending a 3,390-ft jetty con- 

 structed by local interests during 19 16 to 1919. Construction began in 1923, 

 was halted in 1926 due to lack of funds with the jetty 70 percent complete, 

 and completed during 1928 to 1930, The jetty was restored during 1941 to 

 1942, including placing a concrete cap on the outer 3,977 ft. 



102. A short south jetty was authorized in 1930 and constructed during 

 1933 to 1934. In 1935, a 1,700-ft extension was authorized. The work was 

 completed in 1938, including a monolithic concrete block, 46 ft long by 30 ft 

 wide by 16 ft high, placed at the head of the extension and flanked by four 

 wing blocks and two end blocks. The south jetty was then 4,200 ft long and 

 terminated 1,800 ft south of the end of the north jetty. A 550-ft shore con- 

 nection was added in 1940. 



103. The original jetties did not provide an adequate entrance. In 

 addition, the ebb currents met the south jetty at an abrupt angle, causing 

 deterioration and subsidence of the structure. A hydraulic model study was 

 conducted at the US Army Engineer Waterways Experiment Station (WES) during 

 1946 to 1948 to determine the best method of improvement. Based on the model 

 study results, a 4,240-ft training jetty was constructed parallel to and along 

 the south side of the entrance channel during 1950 to 1951. The training 

 jetty terminated about one-half mile short of the end of the south jetty. 



104. The south jetty was rehabilitated in 1963. In 1964, a second 

 hydraulic model study was initiated at WES which recommended extending the 

 training jetty to the end of the south jetty. The north jetty was rehabili- 

 tated in 1977, and the training jetty was extended during 1978 to 1980. 



105. The jetties appear to be in good condition at this time. A chro- 

 nology of events related to the development and repair of the jetty structures 

 is given in Table 31. 



Yaquina Bay, Oregon 



106. Yaquina Bay is located on the Pacific coast of Oregon, 113 miles 

 south of the Columbia River. The town of Newport, Oregon, is located at the 

 mouth of the bay. 



107. The original project was authorized in 1880 and included two con- 

 verging high-tide rubble-mound jetties. The north jetty extended 2,300 ft to 

 the present angle in the jetty, and the south jetty was 3,600 ft long, with 

 the ends of the jetties 1,000 ft apart. The orientation of the jetties was 



30 



