Fortuna Water Hardness & Quality Report (2026)

Fortuna, California, in Humboldt County — a Humboldt County city adjacent to Eureka and Rio Dell on the Eel River in north coastal California — receives its water from the City of Fortuna Water Department, drawing from the Eel River through a surface water treatment facility on California's remote north coast.

The moderately hard 110 mg/L hardness and TDS of 288.2 mg/L are somewhat elevated for a California coastal river supply — the Eel River drains Franciscan Complex rocks (highly sheared melange — largely insoluble) but also passes through Cretaceous Yager Formation calcareous zones that contribute modest dissolved minerals (compare Eureka CA: 105/275 in Humboldt County comparable; Arcata CA: 108/282 in Humboldt County comparable; Fortuna consistent moderate from the same Humboldt County Eel River Franciscan-Cretaceous supply). The Eel River at Humboldt County — Franciscan Complex (insoluble — primary dilutant), Cretaceous Yager Formation (slightly calcareous — primary hardness contributor), and Quaternary Eel River alluvium (slightly calcareous — TDS contributor).

At 110 mg/L with TDS 288, Fortuna's water is moderately hard — mild scale buildup in appliances over time. Semi-annual descaling is appropriate. The PFAS level of 5.3 ppt is moderate — a certified drinking water filter provides added protection. Review the City of Fortuna's annual water quality report for the latest contaminant data, noting any agricultural or timber industry impacts on the Eel River watershed.