Stands of underwater grasses are sprouting this year along Anne Arundel County waterways, some of them appearing in mid-Chesapeake Bay rivers for the first time in more than 10 years.
This new growth means efforts to reduce pollution and clean the rivers feeding the bay are working, said William Matuszeski, director of the Chesapeake Bay Program Office in Annapolis.
"By implication, the water quality has improved," said Steve Funderburk, a biologist with the U.S. Fish and Wildlife Service.
The grasses are valuable as habitat for insects and fish.
A survey of bay grasses has not yet reached Maryland, said a Chesapeake Bay Program spokesman. The office estimated there are 75,000 to 78,000 acres of bay grasses, up from a low of about 38,000 in the mid-1980s. The goal for the year 2005 is 114,000 acres.
At one time, as much as 600,000 acres of varied underwater grasses thrived in the bay watershed. Submerged vegetation has been seen this season in the Magothy, Rhode, Severn, South and West rivers and many of their tributaries. In some areas, the first clumps were spotted only two years ago.
"It's coming back with a vengeance," said James Martin, former president of the Severn River Association.
He and others affiliated with the association said the most common grass has been horned pondweed, though wigeon grass and other species have been found. Bob Evans, president of the Anne Arundel County Watermen's Association, said he has spotted eel weed.
In the South River watershed alone, the increase in grasses may be as much as 300 percent over last year, said John Flood, president of the Federation of South River Associations and surveyor for the U.S. Fish and Wildlife Service.
"Every creek of the river has a consistent band of seaweed," he said. "The mid-bay grasses haven't been around like this in 20, 25 years."
Though horned pondweed is the most common grass seen this year, it is also the least desirable. During the summer, when underwater plants are most needed to produce oxygen, horned pondweed floats through the water, forms clumps and mats, and consumes oxygen as it decomposes.
Yet, "it's better than nothing," said Court Stevenson, a professor at the University of Maryland Center for Environmental and Estuarian Studies.
Peg Burroughs, a former board member of the West River Federation, agrees.
"I don't care if [horned pondweed] is the worst of the grass," she said. "It still supplies something for the little critters to eat and hide in."
Mr. Martin said he prefers to look at horned pondweed as a "pioneer species" and perhaps a sign that other species less tolerant of pollutants will return.
Mr. Stevenson said he expects bay grasses to have a "sub-par year" because of unusually high fresh water runoff this spring and last. The runoff carries nutrients that algae feed on.
The appearance of grasses in Selby Bay in the South River has forced the state Department of Natural Resources to re-evaluate the potential expansion of the Holiday Point Marina, a DNR spokesman said.
Stands of wigeon grass and horned pondweed, some of which weren't there last year, are growing where the marina's owners want to put a marsh to control erosion.
DNR has issued permits for the marsh, but could revoke the permit or seek changes in the plan. The marsh would be created with muck dredged from another area of the expansion. DNR has no deadline for deciding. State regulations ban dredging before October.
Michael Gormley, one of the partners in the marina, said a consultant has said underwater grasses won't hold well at the site because it is too susceptible to erosion.