IV-417 



However, brief flareups of nuisance biological growths have oc- 

 curred and it appears that these nuisance conditions will remain 

 for longer periods of time until a noxious stability is reached 

 (IV-5-10). 



Upper Biscayne Bay, Fla. 



This is one of the many bays on the Florida coast in which the 

 shallow depths allow light penetration sufficient for the growth 

 of submerged vegetation (such as grasses) and algae. Among the 

 impacts of raw sewage discharges into such systems are the 

 limitation of light penetration due to suspended solids and the 

 settling of organic material to the bottom. Both of these impacts 

 affect the submerged vegetation and algae. 



Upper Biscayne Bay is located between Miami and Miami Beach. It 

 is non-uniform in width (2 to 4 nautical miles) and is approxi- 

 mately 6 nautical miles in length. The Miami River enters the 

 southwest portion of the bay (Figure IV. 5. 29). The total number of 

 sewage outfalls entering Upper Biscayne Bay was 70. The Miami 

 River, carrying the sewage from 29 outfalls, was the major pollutant 

 source. It is estimated that 30 to 50 mgd raw sewage flows into 

 the bay. 



Kinds of fixed vegetation divided the bay into two major zones. 

 Along the Miami shoreline was a zone of red algae, which can survive 

 in low light intensities, and most of the surrounding bay was a zone 



