Peace River Basin 



The Peace River basin is drained by the Peace and Myakka Rivers which 

 empty into Charlotte Harbor. A brief discussion of each follows: 



The Peace River originates in the Green Swamp in Central Polk County and 

 flows southwesterly for about 105 mi into the Gulf of Mexico at Charlotte 

 Harbor. The Green Swamp serves as an important recharge area for the Florida 

 aquifer because of numerous lakes and large areas of poorly drained swamps. 

 The Green Swamp itself, because of high recharge characteristics, has been 

 designated as an Area of Critical State Concern. Land use in the upper por- 

 tion of the Peace River basin is predominantly agricultural, but a large 

 percentage (25%) of barren land supports extensive phosphate mining along the 

 river. 



Major pollution sources are domestic sewage discharge, heavy industrial 

 discharges from phosphate mining activities, chemical plants, citrus process- 

 ing plants, and surface runoff. Total Kheldahl nitrogen (TKN) levels are high 

 throughout the river. Mean concentrations vary from a high of 2.26 mg/1 at 

 Bartow to a low of 0.86 mg/1 near the mouth. Average total phosphorus concen- 

 trations show a similar downstream decrease from a high of 3.08 mg/1 to a low 

 of 0.66 mg/1. Mean pH values gradually increase from 6.8 in the upper reaches 

 of the river to 7.9 at the mouth. Relatively low DO concentrations (4.4 mg/1), 

 sometimes below the State water quality standard, have been reported through- 

 out the Peace River. 



The diversity of macroinvertebrates (usually the greater the diversity, 

 the lower the pollution) is reasonably good in the downstream portion of the 

 Peace River. High nutrient and fecal coliform levels and low concentrations 

 of DO in the upper portions of the Peace River are thought to be related to 

 discharges of sewage and industrial effluent in the area. An increase in 

 fecal coliform counts and a decrease in pH and total phosphorus values has 

 been observed in recent years. In general, the water quality in the Peace 

 River improves downstream. In the lower reaches, the water quality is good. 



The headwaters of the Myakka River are the freshwater marshes in Hardee 

 County in southwestern Florida. A salt wedge extends far upstream in Char- 

 lotte Harbor during periods of low flow. Rangeland (45.6% of the total area) 

 and agriculture (26%) are the major land uses in the river basin. The major 

 source of pollution is surface runoff from agricultural and pasture lands. 

 High levels of total phosphorus (0.23 to 0.39 mg/1) has been reported through- 

 out the river. Fairly low concentrations of DO are common in the upper 

 portion of the river (a minimum of 3.8 mg/1) and frequently fall below the 

 State water quality criteria at Sarasota. Concentrations of cadmium, lead, 

 and mercury sometimes exceed the State water quality standards in the Myakka 

 River near Sarasota. Average fecal coliform counts are relatively high below 

 Sarasota (297/100 ml) and at Snook Haven Dock. Macroinvertebrate diversity is 

 reasonably good throughout the river. No overall temporal trend in water 

 quality is evident. In general, the river water quality is good. 



The Tampa Bay River Basin 



The Tampa Bay Basin, which encompasses 3,000 mi^ in four major drainage 

 areas, includes Tampa Bay, Withlacoochee River (including Pitchlachascotee, 



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