The water supply for the cities of Salem and Beverly, Massachusetts has had a long and varied history, since its beginnings in 1864. The City of Salem was authorized to withdraw water from Wenham Lake, by the Acts of the General Court of Massachusetts of 1864, The City of Beverly was subsequently authorized by the Acts of 1885. Pumping to Salem was initiated in 1869 with the development of the Chipman Hill Reservoir, which is located in Beverly. Additionally, piping was laid down Rantoul Street, and also served downtown Beverly. In 1887, Beverly constructed its own system and pump station on Wenham Lake. Over the course of the following year, Wenham Lake was deemed not capable enough to supply the increased population. Augmenting the supply of Wenham Lake, Longham Reservoir was constructed in 1895, by the Acts of the General Court of 1893.

In 1911, both cities petitioned the State of Massachusetts to form a joint Board to develop a common supply. After a two-year study, by an Act of the General Court of Massachusetts of 1913, the Salem and Beverly Water Supply Board was created. Under the conditions of the 1913 Act, the Board was limited to the utilization of the water supply of Wenham Lake and Longham Reservoir and the diversion of water from the Ipswich River. In 1917, the Water Board constructed a 10,000 ft diversion canal from the Ipswich River to a pumping station in Wenham. Plans for a proposed Putnamville Reservoir and treatment study were laid out.

Until the early 1930s, diversions of water to both Salem and Beverly continued without treatment. During the period from 1913 to 1934, the water quality of water pumped from Wenham Lake steadily decreased in quality, with reports of taste, odor, and color problems. Recognizing that a problem existed, the Water Board proposed and constructed a water treatment plant, located adjacent to Wenham Lake in the City of Beverly. Constructed as a Federal WPA (Works Progress Administration) Project, this treatment plant was constructed, completed, and placed in operation on November 1, 1935. It has been in continuous operation since that date. In 1952, Putnamville Reservoir was constructed, adding approximately 1.8 Billion gallons of available water storage. Other than minor alterations to the treatment facilities, the plant remained unchanged until the mid 1970’s.

1975 brought an increase of capacity. Putnamville Reservoir level was raised by 5 feet, the Ipswich River Canal was dredged, and the Longham Dam & Spillway underwent rehabilitation. In 1976-78, the treatment plant was rebuilt to its present configuration of 24 MGD facility (potentially expandable to 32 Million Gallons a Day). To meet the continuously evolving requirements of producing high water quality water, the Board continues to improve and upgrade the treatment process.