ARJWW WATER SOURCES

Where does our water come from and how is it treated?

The Towns of Abington and Rockland are supplied by 3 different sources. The groundwater source, Witherell Merrill WTP, commonly referred to as the Myers Avenue Water Treatment plant, is located on Myers Avenue in Abington. This source consists of 4 gravel-packed wells. The combined effluent from these wells is treated in the "pre-process" with potassium permanganate (oxidizer), aluminum sulfate (coagulant), and sodium hydroxide (coagulant aid). The water is then filtered through a series of pressurized filter vessels filled with a combination of anthracite media and a unique coated media called Greensand Plus. Following this filtration process, the water is then filtered through a Granular Activated Coal media to remove the six per- and polyfluoroalkyl substances (PFAS). Finally, chlorine is added for disinfection and sodium hydroxide is injected into the water to adjust the pH of the finished water for corrosion control.

Our 2 remaining locations are surface water sources. John F. Hannigan Memorial Reservoir, commonly referred to as the Hingham Street Reservoir, is located in the northeast corner of Rockland, and Great Sandy Bottom Pond, is located in the Town of Pembroke. Water from these sources is treated through a conventional treatment process. Aluminum sulfate (coagulant) and either lime (Great Sandy Bottom WTP) or sodium hydroxide (Hingham Street WTP) are added. Potassium permanganate (oxidizer) is also included to oxidize and remove metals such as iron and manganese. At Great Sandy Bottom, the taste and odor of the raw, untreated water is an aspect that has to be addressed in addition to all other attributes of the raw water. Powdered Activated Coal (PAC) is added to the process for taste and odor removal. These chemicals are all introduced at specific dosages to allow impurities to bond together in just the right way. The combined weight causes the unwanted impurities to settle to the bottom, leaving cleaner water (or supernatant) on the top. This product is then filtered through large anthracite coal and silica sand filters. Following filtration, chlorine is added for disinfection, and lime or sodium hydroxide is added for pH adjustment and corrosion control.

These 3 sources combined provide water for Abington, Rockland, and our Joint (Hingham, Whitman, Hanson, and Pembroke) customers.