In comparison Virginia's thriving clam aquaculture is located in areas with significant tidal flows and current, reports Delmarva Now. High levels of water exchange are crucial for the dilution of land sourced pollutants and the waste products created by densely farmed clams.
Virginia's success does come with a cost. Clam farms are unusable for other water-based activities, including boating, swimming, fishing, waterfowl hunting or recreational clamming. Nets, stakes and poles are abandoned or dislodged by storms, and get distributed on beaches, wetlands, and in waterways.
Comprehensive water quality testing by the Coastal Bays Program's Scientific and Technical Advisory Committee began showing deteriorating water quality trends in 2002. In 2004, water quality indicators were developed, with five classifications ranging from "excellent" to "very poor."
Delmarva Now reports that the coastal bays' 250 or so acres of leased bottom are primarily located along the shorelines of Public Landing and Johnson Bay, and run south to the Virginia line. These poorly flushed waters, far from ocean inlets at Ocean City and Chincoteague, showed nutrient levels "above concentrations suitable for maintaining key ecosystem services." Water quality is rated "very poor."
The worsening water quality of Public Landing and Johnson Bay are causing massive brown tide blooms, severe enough to cause nearly 70 percent mortality in juvenile clams.
Like a farmer needs good soil, an aquaculturist needs clean water. Unless the coastal bays clam farms are moved to better water, they are destined to fail.
Maryland: Water Quality Drowning an Industry
MARYLAND, US - The Governor of Maryland - Martin O'Malley - this week spoke on the problems of water quality that hampers the state's aquaculture and threatens to bring yet further problems in the future.