The largest estuary of US, the Chesapeake Bay is on the path of improvement, says "State of the Bay Report."

But the report also claims that the estuary is still dominated by dead zones, killing of fishes and pollution.

The 13 areas in which the estuary performed very poorly have shown some encouraging signs with 8 areas claiming recovery. The population of the blue crabs and underwater grasses are on the positive rise.

But the report is not on the brightest side with the bay still managing only D-plus grade as per the grading system of the report. It is being seen as a development from the 2008 report’s D-grade.

Confirming that the bay is still in a teeter-totter state, William C. Baker, President of the foundation said that it is in a better condition is good news but the bad news is that it is still a system without any balance.

The reports also show that the nitrogen and phosphorous levels are still much higher than what were recommended by the Environmental Protection Agency. This agency is in works to reduce the levels of these gases by one-quarter by 2025.

Storm water pollution, urban and agricultural runoffs and detergents have been traced as the major irritants in the deteriorating condition of the bay.

The bay scores 31 out of 100 and D-plus grade out of the grades which extend till F which are still not even in a satisfying range as per the authorities.