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Boston Harbor: An Environmental Success Story. Cleaning Up MWRA Discharges. MWRA Primary and Secondary Flows. Million Gallons Per Day. Decreased Bacteria Levels in Deer Island Effluent. Number of Days with High Bacteria Counts. MWRA Solids Discharges to Boston Harbor.
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Boston Harbor: An Environmental Success Story
MWRA Primary and Secondary Flows Million Gallons Per Day
Decreased Bacteria Levels in Deer Island Effluent Number of Days with High Bacteria Counts
Questions (and grades) from 1990 “State of Boston Harbor” report • Are marine resources protected? • Is it safe to eat fish and shellfish? • Is it safe to swim? • How does the Harbor rate aesthetically? Overall 1990 Grade was D+
Ampelisca abdita: • Tiny tube-dwelling crustacean • Moderately pollution intolerant • Builds tubes in the sediment
Increased Species Diversity in Harbor Sediment Communities 45 40 35 Species per grab 30 25 20 15 10 91 92 93 94 95 96 97 98
Mussels absorb and concentrate toxic contaminants from the water into their tissue
Decrease in PAH levelsin Mussels Deployed at Deer Island Predeployment LMW Concentration Predeployment HMW Concentration
0-14 Open shellfishing 14-88 Restr. Shellfishing 88-200 Swimming 200-1000 Boating >1000 Poor No Data Map by Suh Yuen Liang
0-14 Open shellfishing 14-88 Restr. Shellfishing 88-200 Swimming 200-1000 Boating >1000 Poor No Data Map by Suh Yuen Liang
Homaris americanus R. Michelson