UMCES Gives a C Grade for 2015 Bay Health in Latest Report Card
The University of Maryland’s Center for Environmental Science (UMCES) recently released their report card on the health of the Chesapeake Bay for 2015. The Bay watershed received a grade of a C, which in comparison to past years, is pretty good. Last year’s grade was a D+; the Bay has not received a grade at or higher than a C since 2002.
The score is calculated by analyzing measurements and factors throughout the different segments of the Bay such as streamflow, fish populations, water clarity, levels of nutrients (total nitrogen and phosphorus), acreage of underwater grasses, types and levels of benthic macroinvertebrates, levels of dissolved oxygen and chlorophyll. Each of the following segments of the Bay receives a grade, and the overall score is an average of these areas (individual grades can be found on page 4 of the report).
The segments of the Bay that were analyzed and scored are:
- Upper Western Shore
- Upper Bay
- Patapsco and Back Rivers
- Lower Western Shore (MD)
- Upper Eastern Shore
- Patuxent River
- Choptank River
- Potomac River
- Lower Eastern Shore (Tangier)
- Rappahannock River
- Mid Bay
- York River
- Lower Bay
- James River
- Elizabeth River
Improvements were found for almost all of the measurements listed above, compared to recent years. Total phosphorus levels in the Bay, however, increased from last year, despite models showing a decrease in phosphorus loadings from tributaries. Further study is needed to explain this.
UMCES points out that only two other years – 2002 and 1992 – had scores as good as 2015. However, 2002 and 1992 were drought years, while 2015 was not. (Drought years are generally good years for water clarity, and nutrient and sediment levels, as there is less runoff entering and polluting the Bay and Bay tributaries). So a question this latest report leaves us with is: Is water quality in the Bay improving? Or is the higher score attributed to other factors, such as the milder water temperatures of last summer?
Chesapeake Bay environment and water quality blog 