The Bay Health Index combines the Water Quality Index and the Biotic Index into a single overarching score. This score therefore evenly combines all six indicators (chlorophyll a, dissolved oxygen, water clarity, aquatic grasses, Benthic IBI, and Phytoplankton IBI) into an overall assessment of Chesapeake Bay health.
Chesapeake Bay - Indicator Details:
This map shows the 2007 Bay Health Index scores for each of the 15 regions. These scores are used to provide report card grades (A to F) for each of the regions. Most regions of the Bay fell into one of two health grades; poor or moderate, with the exception of the Upper Western Shore, which had a moderate–good score. Bay Health Index scores increased in 8 regions in 2007 compared to 2006 and decreased in 6 (incomplete monitoring data available for the Elizabeth River).
This map shows the 2007 Bay Health Index scores for each the 15 reporting regions. The Bay Health Index for each reporting region is the average of the Water Quality Index and the Biotic Index scores.
Comparison of Bay Health Index scores for 2007 () compared to ()
|0 20 40 60 80 100|
|Upper Western Shore|
|Lower Eastern Shore (Tangier)|
|Upper Eastern Shore|
|Patapsco and Back Rivers|
|Lower Western Shore (MD)|
This figure ranks each region from best to worst for the Bay Health Index scores for 2007. The Upper Western Shore and Upper Bay Regions had the highest score because of the high Water Quality Index and Biotic Index scores. Most regions received a poor Bay Health Index score, with the exception of the Upper Bay, James River, and Lower Bay regions which scored a moderate rating. Bay Heath Index scores increased in 8 regions in 2007 compared to 2006 and decreased in 6, (incomplete monitoring data available for the Elizabeth River).
This graph is dynamic, you can: a) show and hide items by clicking them in the legend, b) select year range (click and drag), and c) export as an image.