Deer Island Waste Water Treatment Plant
Encyclopedia
Massachusetts Water Resources Authority
The Massachusetts Water Resources Authority is a public authority in the Commonwealth of Massachusetts that provides wholesale drinking water and sewage services to certain municipalities and industrial users in the state, primarily in the Boston area.The authority receives water from the Quabbin...
is located on Deer Island
Deer Island (Massachusetts)
Deer Island is a peninsula in Boston Harbor, Massachusetts. Since 1996 it is part of the Boston Harbor Islands National Recreation Area. Although still an island by name, Deer Island has been connected to the mainland since the former Shirley Gut channel, which once separated the island from the...
, one of the Boston Harbor Islands
Boston Harbor Islands National Recreation Area
The Boston Harbor Islands National Recreation Area is a National Recreation Area situated among the islands of Boston Harbor of Boston, Massachusetts. The area is made up of a collection of islands, together with a former island and a peninsula, many of which are open for public recreation and some...
in Boston Harbor
Port of Boston
The Port of Boston, , is a major seaport located in Boston Harbor and adjacent to the City of Boston...
. The water treatment plant cost over 3.8 billion dollars making it the seventeenth most expensive object ever constructed. The plant began operating in 1995.
Deer Island is the second largest sewage treatment
Sewage treatment
Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater and household sewage, both runoff and domestic. It includes physical, chemical, and biological processes to remove physical, chemical and biological contaminants...
plant in the United States. The plant is a key part of the program to protect Boston Harbor against pollution from sewer systems in eastern Massachusetts, mandated by a 1984 federal court ruling by Judge Paul G. Garrity in a case brought under the Clean Water Act
Clean Water Act
The Clean Water Act is the primary federal law in the United States governing water pollution. Commonly abbreviated as the CWA, the act established the goals of eliminating releases of high amounts of toxic substances into water, eliminating additional water pollution by 1985, and ensuring that...
.
Operation
The plant removes human, household, business and industrial pollutants from wastewater that originates in homes and businesses in forty-three greater Boston communities. It complies with all federal and state environmental standards and subject to the discharge permit issued for it by EPAUnited States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
and DEP
Department of Environmental Protection
Department of Environmental Protection is a name used by several states in the United States of America for the agency charged with proposing and enforcing environmental law...
. The processing uses heat and microorganisms to break down solids and toxins from the effluent. Its treated wastewater can safely be released into the marine environment. The plant uses primary and secondary treatment to remove 85% of pollution from the water. The resulting effluent is disinfected and then discharged through a 9.5 miles (15.3 km), 24 feet (7.3 m) outfall tunnel into the 100 feet (30.5 m) waters of Massachusetts Bay.
Sludge removed from the waste is sent to an array of twelve 150 feet (45.7 m) egg-shaped sludge digester
Sewage sludge treatment
Sewage sludge treatment describes the processes used to manage and dispose of the sludges produced during sewage treatment.-Sources of sludge:...
s, commonly known as "egg digesters", which are major Boston harbor landmarks. Each digester has a capacity of 3 million USgals (11,356.2 m³) of sludge. Methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
from the digesters is captured and helps power the plant. Digested sludge is piped through a tunnel under the harbor to a plant in Quincy, Massachusetts
Quincy, Massachusetts
Quincy is a city in Norfolk County, Massachusetts, United States. Its nicknames are "City of Presidents", "City of Legends", and "Birthplace of the American Dream". As a major part of Metropolitan Boston, Quincy is a member of Boston's Inner Core Committee for the Metropolitan Area Planning Council...
that converts it to fertilizer pellets.