the same data that was previously published by the American Society 

 of Civil Engineers. The report gives curves of relative run-up 

 versus wave steepness for different slopes with varying degrees of 

 roughness and permeability. Inter-comparison between the curves in- 

 dicates the effect of roughness and permeability, at least for 

 laboratory test conditions. A number of large-scale tests involving 

 waves up to 3^ feet in height were made on a 1 on Ig riprap protected 

 slope using 160-pound rock in an attempt to determine the possible 

 existence of a scale effect. These tests are still underway, but 

 preliminary results indicate the probable existence of a small-scale 

 effect, with run-up being somewhat greater than might be predicted 

 from small-scale model tests. 



(c) Study of Sand Bypassing (derations 



An attempt is being made to gather all available data on sand 

 bypassing operations (past, present, or planned) for correlation and 

 study. The hydrographic survey data obtained in the Port Hueneme area 

 in June 1958 was analyzed, and another survey was made in June 1959. 

 A study was made of the possibility of adapting a density gage (utiliz- 

 ing a radioactive source) and a magnetic type velocity meter for use 

 on bypass operations by hydraulic pumping to determine quantity and 

 rate of pumping. Several combinations which appear readily adaptable 

 for this use are commercially available, but funds have so far pre- 

 cluded purchase or testing of this equipment. 



(d) Laboratory Study of Effects of Groin Field on the Littoral 

 Drift Passing the Field 



A report "Laboratory Study of the Effects of Groins on the Rate 

 of Littoral Transport; Equipment Development and Initial Tests" was 

 published as Technical Memorandum No. 114 of the Board. This report 

 describes the instrumentation and methods of measurement, and the 

 tests made through the summer of 1957." Laboratory tests have been 

 continued, being performed with a single groin on the beach located 

 immediately adjacent to the trap area to give an indication of the 

 time history of the rate of material moving past the groin, and the 

 general location of this moirement (i.e., whether over the top of the 

 groin or around the seaward end of the groin). These tests were 

 performed for a short-lew groin, a short-high groin, and a long-high 

 groin. Tests also were made using two short -lew groins placed adjacent 

 to the trapping eirea and spaced at approximately three groin lengths. 

 Tests were run with different arrangements of side training walls, and 

 complete elimination of one of these training walls, in an attempt to 

 eliminate disturbing reflections from the beach, the side walls, and 

 the generators. 



Two tests have been performed on a steeper (1 on 10) beach slope 

 to determine effect of slope upon test results. Results of these 

 tests, not completely analyzed as yet, indicate that the rate of 



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