All water samples were placed on ice immediately after collection until they were transported back to the lab where they were stored at 4 ◦ C. Water samples were analyzed according to methods delineated by APHA (1995) for TAN (Standard Method 4500-NH3 F. Phenate method), nitrate-N (4500-NO3− F. Cadmium reduction method), and phosphate-P (4500-P E. Ascorbic acid method). Samples were analyzed for TAN and phosphate within 24 h of collection and then frozen. The frozen samples were analyzed for nitrate within 30 day