\ 169 



V 

 further comparative analyses one would hesitate to say that 



at a light transmission figure of X, the transparency with the 



disc is Y. Nonetheless, there is a correspondence and it is 



believed that each method has a certain degree of validity. 



It is recognized, however, that should a photometer be 



devised that measures the net vertical transparency of a 



water column and reduces the measurement to the distance an 



observer could see down into the water, it would be vastly 



superior to either of the instruments now available. 



THE CIRCULATION OF SANTA MONICA BAY 



Statement of the Problem 



Of the physical factors which determine the dispersal of 

 sewage after it has passed through an outfall into the sea, 

 first consideration must be given to the rate and direction 

 of transport by currents, and to the process of eddy dif- 

 fusion. 



It was proposed early in the survey period by members 

 of the project staff that an investigation be made of eddy 

 diffusion. However, in view of the complexity of the pro- 

 blem, it was not at all certain that within the time limit 

 of one year a satisfactory answer could be obtained which 

 would make it possible to forecast the dispersal of sewage 

 from the specific outfalls under consideration. Because one 

 major point of concern revolved about the related problem 

 of the rate of disappearance of coliform bacteria, an intensive 

 study was begun on the organisms themselves, the result of 

 which are described in another section of the report of the 



