Sewer System

In 1833, sanitary waste was allowed into the storm sewer system. 在波士顿，使用雨水下水道排出卫生废物是首次出现的综合下水道系统. 这种做法在整个城市蔓延开来，仅仅一年后, 该市鼓励将屋顶的雨水添加到该系统中，以帮助冲洗下水道中的卫生废物. This flushing did not solve the problem. Health issues related to water contamination, such as cholera, typhoid, and dysentery, began to increase among Bostonians.

Moon Island Reservoirs
In 1875, a study was initiated to address the public health problem, 波士顿主要排水系统(BMDS)的建设. BMDS是波士顿早期下水道系统的原始支柱. BMDS于1877年至1884年在纽约市成立的一个特别委员会的指导下建造. BMDS的目的是截留本地的污水渠，并将卫生废物和雨水径流输送到离岸的处理点. The system included: 25 miles of intercepting sewers, the Calf Pasture pumping station in Dorchester, the Dorchester Bay Tunnel, and an outfall pipe at Moon Island in Boston Harbor. Neither the pumping station nor the tunnel is now in use.  

随着波士顿人口的增长，其城市范围因兼并和土地开垦而扩大, 渠务工程随后扩大，以适应这一增长. 

The BMDS disposed of a substantial portion of the City's waste; however, there were parts of Boston lying outside the service area. 为了解决这个问题，大都会污水处理系统于1889年成立. The first of its kind in the country, 都市污水区包括:北都市污水区, the Charles River Valley Sewer System, and the South Metropolitan Sewer District.

In 1919, to oversee the complex Metropolitan Sewerage District, 马萨诸塞州议会成立了大都会区委员会(MDC), now the Department of Conservation and Recreation. 然而，波士顿主要排水系统继续归市政府所有. 到目前为止，废水只是被收集起来并沉积到波士顿港. Due to worsening pollution, 城市规划者建议在将废水排入港口之前先建造处理厂. 

In response, MDC建造了两个主要的污水处理厂:1952年的坚果岛污水处理厂和1968年的鹿岛污水处理厂. 小牛牧场和月亮岛的出口设施作为鹿岛工厂在潮湿天气时的备用设施. 

In 1977, 下水道系统的所有权和运营责任从市政府转移到新成立的BWSC. In 1985, 麻萨诸塞州立法将所有权转移, control, 并将MDC供水和污水处理部门的运营交给新成立的马萨诸塞州水资源管理局(MWRA)。.

Deer Island Treatment Plant  
一旦控制了系统，BWSC就开始对系统进行修改和改进. In 1988, 新波士顿主拦截器和新东区拦截器的建设已经完成, replacing portions of the original BMDS. 

此外，水务局也正在对该系统进行改进. Between 1997 and 2000, 水务局将鹿岛污水处理厂从一级处理升级为二级处理, 启用连接坚果岛污水处理厂至鹿岛的跨岛隧道, thereby eliminating primary discharge from Nut Island, and completed the 9.5英里的排水口隧道将波士顿港的封闭水域的污水输送到马萨诸塞湾的深水区.

今天，所有由BWSC设施收集的废水都被输送到 MWRA's Deer Island Treatment Facility for secondary treatment. BWSC的废水收集系统服务面积约为20,500英亩. 

该市有两种污水收集系统:分离式和组合式.

• 独立的下水道系统由卫生下水道和雨水渠组成. Sanitary sewers are designed to transport only sanitary flow, whereas storm drains are designed to transport stormwater flows
• 一个联合系统执行双重功能，即在一个被称为联合下水道的管道中输送卫生流量和雨水径流. This type of system is common in older cities

Currently, BWSC工程部每年以卫生污水渠和雨水渠取代合并污水渠，以减少系统中合并污水管的数量.

BWSC污水收集系统全长约1538英里. The system consists of: 710 miles of sanitary sewer, 670 miles of storm drain, 155 miles of combined sewer, and 3 miles of combined sewer overflow pipe. Existing sewers are made of various materials including, but not limited to, stone, brick, slate, wood, vitrified clay, concrete, ductile iron, and cast iron. New sewers and drains are made of reinforced concrete, polyvinyl chloride (PVC) plastic, or ductile iron. Sewers also come in various shapes including, but not limited to circular, rectangular, oval, egg, horseshoe, and U-shaped.

In addition to the wastewater pipes, the system also consists of: 9 pumping stations, 30,327 catch basins, 267 outfalls, 149 regulators, 49,746 manholes, and 201 tide gates.

下水道系统的主干由两个主要的截流器组成:新波士顿主截流器和新东区截流器. Completed in 1988, these interceptors serve the sewer needs of downtown Boston, the South End, Roxbury, Dorchester and South Boston. They provide increased system capacity, 减少潮湿天气的污水溢出排放，并消除干燥天气排放到波士顿港及其支流水域. 其他收集设施为市区其他地区提供污水渠服务.

BWSC有一个更新和更换计划，包括非开挖修复或更换下水道或雨水渠，以应对持续故障, structural deterioration, excessive emergency repairs, and other operation and maintenance problems. BWSC通过电视检查确定需要这项工作的下水道和排水管道, sewer system evaluations, surveys, and routine maintenance activities. BWSC设施收集的所有废水都被输送到MWRA的鹿岛处理厂, after treatment, it is discharged 9.5 miles out into Massachusetts Bay.

所有由波士顿供水和下水道BWSC设施收集的废水都被输送到 MWRA Deer Island Treatment Plant in Boston Harbor.