WATER AND WASTEWATER DIVISIONS

Interceptors

Wastewater collected throughout the system is conveyed to the treatment plant by an interceptor network, comprised of seven major systems located along the banks of the Merrimack and Little Rivers. The interceptors were constructed mainly in the 1970s and are thus considered relatively new when compared to the remainder of the collection system. All of the interceptors convey flow from portions of the combined sewer system. The name, range of pipe sizes, and total length of each interceptor are listed below.

The interceptor system also includes three major river crossings, which carry flow from the north side of the Merrimack River to the south side of the river. A differing number and size of siphon barrels characterize each crossing. Each siphon, along with its size and number of barrels, is listed below.