Public Water Supply in Massachusetts from 2009 to 2022

Consumption of water is a critical issue for the United States (US); a nationwide analysis is provided every five years by the US Geological Survey, but analysis at the state level on an annual basis is lacking. This work investigates the current status and trends of water consumption across Massachusetts public water suppliers (PWS). Monthly data for the years 2009 through 2022 was obtained from the state regulatory authority, the Massachusetts Department of Environmental Protection (MassDEP). After extensive quality control, the final dataset included 280 PWS, ranging from the large system that services the Boston metropolitan region to small rural systems in the western portion of the state. The analysis focused on the following: “How much water is used?” (analyzing the magnitude and trend in annual water consumption as well as the ratio of summer to winter consumption), “Where is the water coming from?” (analyzing the contribution of surface water, groundwater, and purchased water sources to each PWS’ supply), and “Where is the water going?” [analyzing percentage of customers that are residential, the residential gallons per capita per day (RGPCD), and unaccounted for water (UAW)]. RGPCD and UAW are of particular interest because they are tied to the MassDEP permitting process by which PWS are authorized to withdraw water. Key results from the analysis are: first, water consumption is not changing for many PWS; second, many PWS are solely reliant on groundwater; third, while most PWS have an RGPCD below the threshold of 65 gallons per day, in contrast most PWS have an UAW above the threshold of 10%. The results of this work provide critical decision-support information to MassDEP who determines statewide regulations and to PWS who must comply with those regulations while also continuing to provide clean and abundant water to their customers.