It seems reasonable to conclude that outflow of phosphate-rich water 

 from the Peace River does not ordinarily enrich the Gulf waters to any appre- 

 ciable degree. 



There is evidence, however, that under conditions of unusual rainfall 

 some effect of outflow from Charlotte Harbor is noticeable, at least close 

 inshore. From figure 2 it can be seen that the only case in which a rise in 

 phosphorus in the ship channel (Station h ) was accompanied by a rise in 

 Charlotte Harbor (Station 3) was during the September 19^9 survey. 



These observations were made from August 20 to September 1 following a 

 month of unusual rainfall. Associated with these high values of phosphorus 

 were very low values of salinity. This was the only period in which there 

 was any appreciable freshening of the water in Charlotte Harbor or in the 

 ship channel. 



Table 3. —Concent ration of phosphorus at surface (approximately 1 meter) 



at stations on 10- and 20-fathom lines. Values, in ug-at/L, are 

 means for five cruises during the period Sept. 20,. 1950 to 

 Jan. 19, 1951. 



During the hurricane of August 19U9 a slime dam containing phosphate 

 sludge at one of the mines broke, releasing large quantities of phosphate 

 which drained into the Peace River. This probably accounts for the high 

 phosphorus values found in the Peace River during the September and October 

 surveys and in Charlotte Harbor in the September survey. The high value at 

 Station k in this survey j s probably related to this also as the salinity 

 was low there at that time indicating an unusual flow nf water out of the 

 Pass. The relatively high phosphorus values at Station h in the following 

 months (October to November) may possibly be related to this also. However, 



10 



