Historic changes in shoreline position exhibited consistent trends along 

 shoreline Segments 2 and 3. The southern region of shoreline between the 

 Santa Ana River and Huntington Pier experienced shoreline progradation for 

 every measured time interval except that between 1958 and 1963. The northern 

 coastal segment from Huntington Pier to Anaheim Bay experienced both erosion 

 and accretion; however, shoreline progradation was dominant between 1934 and 

 1983. A more comprehensive discussion of historical shoreline changes in this 

 region is provided by Gravens (1988) and Signal Landmark (1988). Finally, the 

 shoreline position data for the years 1963, 1970, and 1983 were assembled at 

 200-ft intervals (the cell spacing used in the shoreline change simulations) 

 for use in the shoreline change model. 



Wave Data 



Three parameters are used by both the shoreline change model and the 

 nearshore wave transformation model to describe the characteristics of the 

 wave climate. These are the significant wave height, dominant wave period, 

 and incident wave angle. 



Four sources of wave data were available for application to the project 

 coast during the conduct of the preliminary shoreline response study. These 

 are the Marine Advisors (MA) (1961) hindcast, the National Marine Consultants 

 (NMC) (1960), hindcast, two U.S. Army Corps of Engineers Littoral Environment 

 Observation (LEO) Stations (Sherlock and Szuwalski 1987), and a slope array 

 wave gage maintained by Scripps Institution of Oceanography (SIO). 



The NMC and MA hindcasts cover the years 1956, 1957, and 1958, and 

 provide percent occurrences for given deepwater wave heights and periods. 

 Since the shoreline change model requires a time series of input wave condi- 

 tions, the hindcast wave data were used for statistical comparison purposes 

 only. The LEO program had two stations on the project coast, at Bolsa Chica 

 and Huntington Beach. LEO data are available for the Bolsa Chica station from 

 October 1979 to May 1982, and for the Huntington Beach station from October 

 1979 to April 1985. The LEO program provides daily visual estimates of the 

 breaking wave height, angle, and period, as well as other littoral environment 

 data. A 1-year time history of wave data was selected from each of the LEO 

 stations for use in the comparison of available wave data. 



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