(2) Cattaraugus Creek Harbor, New York . 



(a) Project . Jetties for wave protection, passage of flood- 

 flows and ice, and prevention of shoaling. 



(b) Reference . Bottin and Chatham (1975) . 



(c) Laboratory . WES. 



(d) Test Period .- May 1974 to April 1975. 



(e) Problem . Stream discharges on Cattaraugus Creek move 

 sediment (sand and gravel) downstream where it is deposited on a delta 

 at the creek mouth. Wave action from Lake Erie rearranges this material 

 to form a bar across the creek mouth. This bar restricts navigation and 

 provides a natural barrier, resulting in the formation of ice jams and 

 flooding of the low- lying surrounding area. 



(f) Purpose of Model Study . The model study was conducted 

 to develop the most cost-effective jetty arrangement at the creek mouth 

 which would prevent shoaling, provide wave protection, and allow the 

 passage of floodflows and ice. 



(g) The Model . The undistorted, l:75-scale hydraulic model 

 reproduced the lower 5,400 feet of the creek channel and underwater con- 

 tours in Lake Erie to offshore depths ranging from -38 feet on the north 

 to -18 feet on the south (Fig. 5-5). The total area reproduced in the 

 model was approximately 16,380 square feet, representing about 3.3 square 

 miles in the prototype. 



(h.) Test Procedures. Tests consisted of measuring wave 

 heights, wave- and stream-generated currents, and water surface profiles 

 for various stream discharges; obtaining photos of wave, current, and 

 shoaling patterns; and qualitative investigations of ice- jamming tenden- 

 cies using a low-density polyethylene material to simulate ice fragments. 

 Using the procedures discussed previously for the scaling relations of 

 Noda (1972), crushed coal and granulated nylon were selected as tracer 

 materials to simulate the prototype sand (median diameter, 0.25 milli- 

 meter; specific gravity, 2.65). Initial model tests indicated that 

 relative deposits for these two materials were almost identical. The 

 main difference was that the larger nylon particles were more sensitive 

 to wave action and, in general, did not deposit on the beach or form bars 

 as readily as coal. Considering the behavior of the two materials and 

 field observations of shoaling at the existing harbor, it was decided 

 that the crushed coal more reliably reproduced the prototype shoaling 

 patterns and coal was used for all subsequent tests. 



(i) Plans Tested . Tests were conducted for one jetty 

 arrangement with the entrance oriented to the southwest and for several 

 modifications of length, orientation, type (sheet pile or rubble mound), 

 etc. of a jetty arrangement with the entrance oriented to the north. 



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