Marion Water Hardness & Quality Report (2026)

Marion Water Department (also known as Marion Municipal Water Dept) serves approximately 42,000 citizens across Marion and nearby areas in Linn County, Iowa, through 207.8 miles of water mains and 15,268 service connections. The primary source is the Jordan aquifer (67% of supply in 2022), accessed via four deep wells each yielding up to 1,500 gallons per minute. Supplementary supply comes from the Silurian aquifer (33%) via four shallower wells. The utility conducted over 3,750 tests in 2022 to ensure EPA compliance.

Water from the Jordan aquifer originates in recharge areas of northeast Iowa and southeast Minnesota, traveling 1,600 feet through Cambrian sandstone formations protected by overlying materials that limit contamination susceptibility. The Silurian aquifer draws from the Cedar River Basin, with dolomite and limestone layers influencing chemistry. These ancient Paleozoic rock formations dissolve calcium and magnesium minerals over long groundwater residence times, yielding a hard supply; the aquifers' depth provides natural filtration but elevates dissolved solids.

Hard water promotes scale buildup in pipes, heaters, fixtures, water heaters, dishwashers, washing machines, and coffee makers, reducing efficiency and lifespan; soap lathering is reduced, leading to drier skin and hair. Maintenance tips include regular descaling of appliances, installing sediment filters, and flushing hot water tanks annually; a water softener is recommended to mitigate these effects and extend equipment life. The 2022 Consumer Confidence Report confirms all EPA standards are met, with low contamination susceptibility for the Jordan aquifer; tapwaterdata.com notes 3 contaminants above health guidelines, yielding a quality score of 70/100, with no specific MCL violations listed.