Overall Health Index

The Chesapeake Bay report card compares 7 indicators (dissolved oxygen, nitrogen, phosphorus, chlorophyll a, water clarity, aquatic grasses, benthic community) to scientifically derived thresholds or goals. These indicators are combined into an Overall Health Index, which is presented as a subregion percent score. Other indicators (blue crab, bay anchovy, striped bass) presented on these pages are not included in the score.

Many indicators are important in determining the overall health of Chesapeake Bay.