Woburn Water Hardness & Quality Report (2026)

Woburn, Massachusetts, in Middlesex County — a major north Boston suburban community, the hometown of Count Rumford (Benjamin Thompson, the 18th-century physicist and inventor — born in Woburn in 1753), a city with a significant environmental history (the 'A Civil Action' case — the famous contamination litigation immortalized in Jonathan Harr's book and the 1998 film — arose from Woburn's Industri-Plex EPA Superfund site and the Wells G&H trichloroethylene contamination), and a diverse Middlesex County technology corridor community — draws its municipal water supply from Horn Pond via the City of Woburn Water Division supplemented by the MWRA. Water hardness in Woburn measures 120.5 mg/L — classified as moderately hard.

Woburn's moderate hardness — harder than most Massachusetts communities — reflects the Middlesex Fells watershed's calcareous-moderate geology. The Horn Pond watershed at Woburn drains: the Middlesex Fells (Precambrian calcareous-moderate hornblende gneiss and amphibolite — the Middlesex Fells amphibolite-bearing metamorphic terrain, significantly more calcareous than the pure granite terrain elsewhere in eastern Massachusetts); and Triassic–Jurassic diabase intrusions (calcareous-moderate mafic intrusive rock of the Woburn area). These calcareous-moderate mafic rocks produce the higher-than-average Massachusetts hardness of 120.5 mg/L.

At 120.5 mg/L, Woburn residents encounter moderate scale accumulation. Monthly cleaning with citric acid solution is recommended. City of Woburn Water Division consistently delivers water meeting all Massachusetts MassDEP and EPA Safe Drinking Water Act requirements.