Northridge Water Hardness & Quality Report (2026)

Northridge, California, a residential neighborhood in the north-central San Fernando Valley within the City of Los Angeles — known for the 1994 Northridge earthquake (epicenter in the Northridge–Reseda area) and California State University, Northridge — receives its municipal water supply from the Los Angeles Department of Water and Power (LADWP), sourcing from a blend of Owens Valley Aqueduct (Eastern Sierra Nevada), State Water Project (SWP) imports, and local San Fernando Valley Groundwater Basin pumping. Water hardness in Northridge measures 112 mg/L — classified as moderately hard.

Northridge's moderate hardness — substantially higher than western Valley neighborhoods like Woodland Hills (42.5 mg/L) — reflects greater local San Fernando Valley Groundwater Basin contribution in the central and north-central Valley zone. The San Fernando Valley Groundwater Basin in the Northridge–Reseda–Chatsworth area includes multiple LADWP production wells and the Chatsworth Reservoir area. The alluvial fan groundwater in the north-central Valley has experienced more calcareous dissolution from the Santa Susana Mountains (Cretaceous Chatsworth Formation — calcareous conglomerate and sandstone) and the Transverse Ranges calcareous terranes. Additionally, the Northridge zone distribution infrastructure is older (1940s–1960s era of north Valley development) than the more recent western Valley areas.

At 112 mg/L, Northridge residents encounter moderate scale accumulation. Faucet aerators and showerheads develop deposits after several months — monthly cleaning with citric acid solution is practical maintenance. LADWP consistently delivers water meeting all California SWRCB and EPA Safe Drinking Water Act requirements.