ANNAPOLIS, Md. (AP) — The Chesapeake Bay watershed received an overall grade of C+ on its latest report card, released Monday by the University of Maryland Center for Environmental Science.

The Chesapeake Bay health score improved slightly from 45 to 50 last year, for a grade of C, the report said.

The health of the bay is a reflection of what is happening across its six-state watershed, which includes Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia and the District of Columbia.

“This year’s report card is the first to include a range of economic, ecological, and societal factors to help assess progress in improving this vast human and natural system that is a major component of the quality of life for people in the region,” Dr. Peter Goodwin, president of UMCES, said in a news release.

While individual indicators of bay health had mixed results in 2021, the overall trend is improving, the center found.

Seven reporting regions had improved grades due to better water quality — both nitrogen and phosphorus concentrations continue to improve — and the aquatic grass coverage is improving, but water clarity and chlorophyll continue to degrade.

The highest-scoring region was once again the Lower Bay, with 65%. The Patapsco, Back and Patuxent rivers scored lowest, at 23%.

However, long-term trends still show significant improvements in the James River, Elizabeth River, Patapsco and Back Rivers, and Upper Western Shore.

One exception is the Upper Eastern Shore, where the center blames polluted runoff from chicken farms for the first declining trend observed in any reporting region since 2014.

Building on social indicators that were added in 2021, new economic indicators were used to evaluate the health of local economies in the region. These include median household income, jobs growth, income inequality, and housing affordability.

The analysis of Chesapeake watershed health is based on 23 reporting regions and incorporates economic, ecological, and societal indicators.

UMCES said the information is critical to supporting and informing policy and other decisions related to diversity, equity, inclusion, and justice issues, especially around environmental justice. UMCES will begin to evaluate these relationships over the next several years, beginning with the 2022 Chesapeake Bay Watershed Report Card.

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