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The State of the Bay
Dan Simon
 The
state of the Chesapeake Bay isn't getting any better.
That's the conclusion in this year's State of the Bay report by the
Chesapeake Bay Foundation, who's annual summary of the bay's health
may actually be hiding some bad news.
The organization uses a 0 to 100 scale, with 100 representing what
the bay was probably like more than 400 years ago when Captain John
Smith first described the bay he visited. For the past two years the
bay's health has earned a 27 rating, leaving it in what the foundation
describes as "critical" condition.
The most significant factor this year, as in years past, is the amount
of nitrogen pollution entering the bay. Estimates are the Chesapeake
Bay receives more than 300 pounds of such pollution each year, six
times what scientists estimate it can handle and stay healthy. Nitrogen
pollution affects many of the criteria the foundation uses to judge
the bay's health, so its impact of particular concern.
What makes this year's apparent equilibrium misleading, is since most
of the year has been in drought conditions, runoff levels have been
low, likely reducing the amount of nitrogen pollution entering the
bay compared to what might have happened during a normal rainfall
year.
The nitrogen enters the bay as runoff from fertilizers applied to
lawns and farms, power plants, vehicles and sewage treatment plants.
More than 15 million people live on the 64,000 square miles that make
up the bay's watershed.
 A
certain amount of nitrogen is necessary in a system to help support
life, but excess amounts over an eco-system's historic levels can
throw that system out of balance. For instance, high levels of nitrogen
in the Chesapeake Bay are blamed for algae blooms which block sunlight
from reaching underwater grasses. Those grasses currently cover about
75,000 acres of bay area, about half as much as the foundation's goal
for the future. When the algae dies, it sinks to the bottom of the
bay, where its decomposition uses up oxygen that would normally support
aquatic life.
The foundation estimates nitrogen pollution entering the bay would
have to be reduced by 150 million pounds annually to help bring the
bay up to a rating of 40, which under their scale would remove the
bay from their list of the nation's dirtiest waterways. The organization's
goal is to reach that level by 2010.
The foundation uses 13 indicators in three categories (habitat, pollution,
fisheries) to measure the bay's health. Rockfish (75), forested buffers
(54), wetlands (42), and crabs (40) are the only indicators at the
40 mark or above. Oysters (2) and Shad (7) are in the poorest health
according to the report. The overall rating of 27 does indicate a
small improvement over the bay's lowest ratings in the 1980s.
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