259 



to the shelf water. Under such conditions a rather strong 

 flow to the north along the coast is apparent. Other water 

 units with colder or warmer temperatures, but with normal 

 salinities occur at intervals in various parts of the bay 

 and are related to minor complex patterns of currents. Some 

 of these patterns recur with a frequency that can be correlated 

 with weather conditions on a seasonal or non-seasonal basis. 

 Others represent single isolated instances of unusual reactions 

 by the water to weather and tidal conditions that happened to 

 occur concurrently. Because the patterns of water units are 

 complex, as are the resultant currents, prediction of water 

 motion under a given set of conditions is still somewhat 

 hazardous with the data at hand. However, the currents are 

 by no means erratic and the net motion over a period of 

 several days can be forecast with a reasonable degree of 

 accuracy. 



Water Temperature 



Thermoclines and substantial temperature differences 

 between the surface and bottom water were best developed 

 during the summer. These temperature conditions are most 

 favorable for the suppression of the effluent below the sur- 

 face, although even then the rising sewage may reach the 

 surface . 



Inversions were characteristically present in the boil, 

 area, indicating the turbulent nature of the rising effluent 

 column. Inversions were also encountered in both the southern 

 and northern reaches of the bay where upward displacement of 



