Water Quality

NPS Assertion: Removing the oyster farm would
improve the water quality of Drakes Estero

The FEIS created by the Park Service claims:  “Overall, Alternative A [removing the oyster farm] would result in long-term beneficial impacts on water quality as a result of reduced non-point-source runoff and the elimination of future disturbances to the Drakes Estero bottom from boats and offshore structures.”

Alternatives that allow the oyster farm to remain are alleged to have “short-term and long-term minor adverse impacts on water quality due to onshore and offshore activities associated with commercial shellfish operations in Drakes Estero.”

There is no known evidence for these claims.

DBOC Assertion: Oyster farming enhances water quality
The National Academy of Science report points out that there is ample evidence that oyster culture results in clean water, reporting “To varying degrees, suspension feeders enhance benthic-pelagic coupling, nutrient remineralization, primary productivity, sediment transfer from water column to the bottom, and habitat complexity. Kaiser (2011) reviewed the effects of shellfish cultivation on estuarine ecosystems and identified a similar set of mechanistic influences, concluding that such processes have a generally positive influence on the overall water quality of a system. Oyster enhancement and oyster reef restoration is a major and expanding component of estuarine restoration throughout the United States.”