Concentrations of natural organic nitrogen (TKN and Org-n) were highest 

 in wetlands with water storage, and in rangelands. Sewage flow also was 

 highly correlated with nitrogen concentrations. High levels of organic nitro- 

 gen appear to be caused by agriculture and industry because of nitrogen 

 fertilizer used on agricultural lands. 



Increases in biological oxygen demand (BOD) were directly related to 

 increases in sewage flow. Dissolved oxygen was negatively correlated with 

 wetlands and rangeland. This agrees with the BOD analysis. Runoff from 

 rangelands and washed out organics from wetlands could indirectly cause oxygen 

 depletion in the receiving waters. Increased sewage often decreases dissolved 

 oxygen concentrations because of an increase in BOD. 



The best available forecast for sewage treatment plant flows for the 

 seven counties is given in Table 2. This forecast and relevant population 

 projections by the University of Florida suggest a moderate 2% to 2.5% annual 

 population growth. Without greater pollution control, water quality may 

 decline because of increased point source loadings from secondary treatment 

 facilities and industrial expansion. 



Increased urbanization, industrialization, and water related development 

 suggest that in some areas water quality may decline within the next several 

 decades. The specific amount of decline is difficult to predict within any 

 degree of accuracy and, therefore, should only be identified in terms of 

 direction and probable magnitude. 



Phosphorus and nitrogen concentrations may increase as agricultural 

 activity intensifies and expands. As urbanization expands in Northwest Flor- 

 ida, forest areas will be cleared and marsh wetlands drained. As a conse- 

 quence, BOD, DO, inorganic nitrogen, and phosphorus also will increase. 

 Adequate regulatory controls, including permits for point source and regula- 

 tory management of nonpoint sources, minimize violations of water quality 

 standards in Northwest Florida. 



COASTAL RESOURCE ISSUES 



Class II and III Salt and Brackish Water 



Saltwater areas identified under the Class III designation are for propa- 

 gation of saltwater species of aquatic life and for recreation. A special 

 classification also is designated for shellfish. The Class II designation is 

 often far more restrictive because of the filter-feeder nature of the shell- 

 fish growing within the particular Class II designated areas. Shellfish often 

 absorb and biomagnify certain pollutants in the feeding process. They are not 

 able to relocate or avoid pollution as are more mobile species. The discus- 

 sion of Class II and Class III standards will be incorporated under the 

 general coastal resource designation. Where necessary, differentiation 

 between Class II and Class III will be made. The aquatic resources under con- 

 sideration here are Apalachicola Bay, Choctawhatchee Bay, East Bay, Escambia 

 Bay, Perdido Bay, St. Andrews Bay, and St. Joseph Bay. 



In general, estuaries are characterized by a high level of dissolved 

 oxygen, medium chlorophyll-a_ and DO concentrations, and low to medium coliform 



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