The Coastal Bays Monitoring Program measures key components of the ecosystem, including pollutant inputs, water quality, habitat and living resources. The information is vital for evaluating the progress of management actions aimed at protecting and restoring the Coastal Bays and tributaries, for our efforts to address emerging issues such as Harmful Algae Blooms and to provide guidance for future actions. Monitoring data is also used for research and efforts to model the ecosystem.

View water quality monitoring plan and stations map.

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Water quality is degraded in the tributaries and better in the open bays.

A Water Quality Index was developed to synthesize the status of the four main water quality indicators (chlorophyll a, total nitrogen, total phosphorus, and dissolved oxygen) into a single indicator of water quality. This indicator is similar to the Dow Jones Index, which compiles information on multiple stocks and provides a simple number to track over time. 

The Water Quality Index compares measured variables to values known to maintain fisheries and seagrasses.  This index is a number between zero and one, with a score of 0.8 and above and indicator of good water quality for fish and seagrasses, and a score below 0.4 indicating poor water quality. Each monitoring station was scored from data collected between 2001 and 2003.  View water quality index map.

Currently, tributaries generally show poor to very degraded water quality largely due to high nutrient inputs, while the open bays have good to excellent water quality.  Also, the northern bays are generally in poorer condition than the southern bays.

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