Phosphorus

Phosphorus is a second primary contributor to the algae blooms and dead zones that are killing the Bay.

The amount of phosphorus entering the Bay annually has been reduced by 8.9 million pounds since 1985.  A large part of this success was due to the bans on phosphorus-containing laundry detergents enacted in the late-1980s.  However, we are still only 62% of the way to our goal of limiting phosphorus pollution to 12.8 million pounds per year by 2010.

Forty-five percent of the phosphorus reaching the Bay in 2005 originated from agricultural sources, with run-off from manure alone accounting for 27% of all phosphorus pollution.  Urban and suburban fertilizer run-offs combined with phosphorus-containing sediment already existing in streams were responsible for 30% of the new phosphorus reaching the Bay.  Municipal and industrial wastewater treatment facilities accounted for 22% of the phosphorus pollution load, and wildlife and forestry sources accounted for the final 3%.