Back Bay
(CBBBBB)
Portland

CHART    N 43° 40'43.9" W 70° 15'35.4"

Back Cove

A shallow tidal mud flat, Back Cove has been filled in over the past hundred years. Today it is a fraction of its original size. Until mid 1970, much of Portland's wastewater flowed directly into Back Cove. Today it is popular recreationally, especially among windsurfers. Back Cove also offers an important marine worm habitat. It is an important migratory waterfowl wintering and stopover area and is designated a wildlife sanctuary.

Land use in adjacent areas is heavily residential. Although sanitary wastewater discharges have been controlled, stormwater continues to discharge to the Cove. In the past few years, many debates have centered on the contribution of pollutants from the municipal snow dump on the shore of Back Cove and its effect on the biota.

Mussels were collected along the east shore adjacent to the main channel and up two central channels. Metal concentrations are generally higher than the Cask Bay average. When first sampled in 1988, lead was highly elevated (315% above the normal range). Eight years later, after the phase-out of leaded gasoline, lead had dropped to 120%. Copper and nickel concentrations are also highly elevated; however, we have no explanation for these large differences. Follow-up samples must be collected to verify levels of these two metals.

Actual Concentration (mg/g dry weight) of Heavy Metals in Mussel Tissue