Columbia Water Hardness & Quality Report (2026)

Columbia, Tennessee, the Maury County seat — a major central Tennessee city south of Nashville (Columbia is the Maury County seat and a major I-65 south Nashville suburban community), historically the 'Mule Capital of the World' (Columbia hosted the world's largest annual mule market from the late 19th century through mid-20th century — Maury County was the center of the mule-trading industry that supplied mules to southern farmers and military forces in WWI and WWII), home of James K. Polk's ancestral home (the only surviving home of the 11th US President — Polk was born near Columbia and lived in the Columbia area), and a diverse Maury County community in the booming Nashville south metro — draws its municipal water supply from the Duck River via the City of Columbia Water Division. Water hardness in Columbia measures 198 mg/L — classified as hard.

Columbia's very hard supply reflects the Maury County Duck River watershed's highly calcareous Tennessee Paleozoic carbonate geology. The Duck River at Columbia–Maury County drains: the Ordovician Knox Dolomite (highly calcareous dolomite of the Nashville Dome outer rim — the central Tennessee calcareous Ordovician carbonate); the Mississippian Warsaw Formation and St. Louis Limestone (highly calcareous marine limestone of the Tennessee Paleozoic Platform); and the Devonian calcareous Chattanooga Shale and underlying carbonate sequence. City of Columbia treatment produces the hard 198 mg/L.

At 198 mg/L, Columbia residents face regular hard water challenges. Monthly descaling with citric acid solution is recommended. City of Columbia Water Division consistently delivers water meeting all Tennessee TDEC and EPA Safe Drinking Water Act requirements.