Northridge Water Hardness & Quality Report (2026)

The Los Angeles Department of Water and Power (LADWP) supplies Northridge, California, in the San Fernando Valley portion of Los Angeles County. Water comes from mixed sources: 50–60% imported surface water via the Los Angeles Aqueduct drawing from the Owens River and Lake Crowley reservoirs in the Sierra Nevada, 20–30% from the California State Water Project delivered through the Jensen Water Treatment Plant and Skinner treatment plant, and 10–20% local groundwater from wells in the San Fernando Groundwater Basin. Treatment also occurs at the Headworks Treatment Plant, with groundwater receiving chloramination or minimal processing.

The local San Fernando Valley Groundwater Basin holds the Alluvial Aquifer formed in Quaternary-age sediments — Holocene and Pleistocene sands, gravels, and silts overlying Tertiary sedimentary rocks including the Pico Formation and Fernando Formation (Miocene). Imported aqueduct water from the Eastern Sierra Nevada and Colorado River traverses carbonate-rich terrain, while local groundwater dissolves calcite, dolomite, and gypsum from basin-fill sediments, imparting a moderately hard, mineralized character to the supply.

Moderately hard water promotes scale buildup in pipes, water heaters, dishwashers, and washing machines, reducing efficiency and raising energy costs. Soap lathering is reduced, leading to more detergent use and potential dry skin or spotted dishes. Regular descaling with vinegar and annual water heater flushes are recommended; a water softener will extend appliance life. LADWP water meets federal standards with pH 7.5–8.5; no PFAS exceedances are reported, and disinfection byproducts including TTHMs and haloacetic acids remain within legal limits.