Paramount Water Hardness & Quality Report (2026)

The City of Paramount Water Department serves approximately 55,200 residents across Paramount, California (Los Angeles County, PWSID CA1910105), operating from 16400 Colorado Avenue. The utility draws from the Central Basin and West Coast Basin aquifers underlying the Los Angeles Coastal Plain. Water is treated at local facilities and distributed throughout the service area. The utility publishes annual Consumer Confidence Reports detailing water sources, testing protocols, and compliance with state and federal standards.

Paramount's water supply originates from Quaternary alluvial aquifers and deeper Pliocene–Miocene marine sedimentary formations beneath the Los Angeles Coastal Plain. These geological units contain abundant calcium and magnesium minerals — particularly carbonates and silicates — which dissolve into groundwater as it percolates through the aquifer matrix. The hydrogeology of the Central and West Coast Basins naturally produces hard water; this mineral-rich character is typical of Southern California's coastal groundwater systems and reflects the region's depositional history.

Paramount's water is classified as very hard, with dissolved solids and mineral content creating visible impacts including scale buildup on fixtures, reduced soap lathering, and reduced appliance lifespan and energy efficiency. Water softening is strongly recommended for households and businesses; regular scale removal and maintenance of water-using appliances are important practical considerations. Despite this hardness, the City of Paramount Water Department reports an overall quality grade of A (Excellent) with a score of 100/100 — all 224+ contaminants tested remain within EPA Maximum Contaminant Level Goals, with zero violations. The utility conducts routine water mainline flushing to maintain distribution system quality, and annual Consumer Confidence Reports are available at paramountcity.gov.