proposed plans were limited to the most critical direction of wave approach 

 (i.e., 1 1 deg). Wave-gauge locations are shown in referenced plates. 



Sediment-tracer experiments. Sediment-tracer experiments were conducted 

 for existing conditions and selected plans of improvement for representative 

 experimental waves from the various incident directions. In most cases, sediment 

 tracer was introduced into the model along the shoreline north of the harbor to 

 define sediment-tracer patterns and subsequent deposition areas. 



Wave-induced current patterns and magnitudes. Wave-induced current 

 patterns and magnitudes were obtained for existing conditions and selected 

 improvement plans for representative experimental waves from the various 

 incident directions. These experiments were conducted by timing the progress of 

 a dye tracer relative to a known distance on the model surface at selected locations 

 in the model. 



Vessel-wake experiments. Wave heights were obtained in the harbor as a 

 result of various vessel wakes for existing conditions and selected improvement 

 plans. Experiments were conducted for four vessels entering and leaving the 

 St. Clair River. The maximum wave height in the wave train was measured 

 during these experiments, as opposed to the significant wave height. The vessels 

 were navigated along the channel center Une. The types of vessels available and 

 the speeds in which they were navigated are shown below. 



Description of Vessel 



Navigation Speed, l<nots 



27-m-lonq (90-ft-lonq) Speed boat 



15 



30-m-long (100-ft-lonq) Cabin cruiser 



12 



183-m-long (600-ft-long) Ore carrier 



7 



210-m-long (690-ft-longX^Container vessel 



6 



Experimental results 



In analyzing results, the relative merits of various improvement plans were 

 based on measured wave heights, wave-induced current patterns and magnitudes, 

 and the movement of sediment-tracer material and deposition areas. Model wave 

 heights were tabulated to show measured values at selected locations. Wave- 

 induced current patterns and magnitudes, and sediment-tracer patterns were super- 

 imposed on photographs. 



Existing conditions. Results of wave-height experiments for existing condi- 

 tions are presented in Tables 6 (no flow conditions) and 7 (riverflow conditions). 

 For the 11 deg direction, maximum wave heights^ were 1.8 m (5.9 ft) in the harbor 

 entrance (Gauge 1); 1.43 m (4.7 ft) in the southwest portion of the harbor 

 (Gauge 3); 1.74 m (5.7 ft) in the northwest portion of the harbor (Gauge 4); and 



^ Refers to maximum significant wave heights throughout report. 

 Chapter 6 Physical Model 



43 



