That far out in the bay, the water is 100 feet deep and the currents are strong. According to MWRA Director of Communications Johnathan Yeo, this, combined with the more disinfected water that emerges from the outfall, makes it "unlikely that any one living fifteen miles away on Cape Cod will feel effects from the new outfall pipes."

Yeo says his statements about the new outfall are supported by scientists from four major Boston-area universities including Harvard.

"Predictions, tests, and data on the new outfall all seem to indicate that this is a safe system. It is certainly much cleaner and healthier for the environment in general and the harbor in particular," Yeo says.

In deep water

Though just outside the city that pioneered the concept of water and sewer systems in early America, Boston Harbor lay nearly biologically dead in the mid-1980s. Besides the unsightliness of the harbor that formed the backdrop of Bush's political advertisement, Boston Harbor experienced large-scale and wide-ranging ecological problems.

In violation of the Federal Clean Water Act of 1972, which mandated that cities put all wastewater through two filtering processes before releasing it into the ocean, Boston had been pumping improperly treated sewage into the harbor for years.

As a result, many types of shrimp fishing had been prohibited by 1970 because of the tendency of the shellfish to accumulate toxins. The harbor's famous lobster population was all but decimated. The Charles, Chelsea, Mystic, and Neponset River estuaries--the portions of the rivers where fresh and salt water converge--were also nearly devoid of the diverse wildlife that is typical of such areas.