Total phosphorus
Fig. A1 (from MPCA 1994 TMDL report). Percent contribution of total phosphorus by sector during the critical low-flow period.
During one 61-day low- flow period in the summer, the average daily load of phosphorus was 767 pounds at Jordan, Minn.
Note the high point- source (treatment plant) contribution of more than 65%; during normal flow, source points contribute only about 9%.