Pittsburg Water Hardness & Quality Report (2026)

The City of Pittsburg utility serves approximately 62,500 residents in Pittsburg, Contra Costa County, California, purchasing its surface water primarily from the Contra Costa Water District (CCWD). CCWD sources water from the Sacramento-San Joaquin Delta via intakes including those at Clifton Court Forebay, with treatment at facilities such as the Mallard Plant and Randall Plant. The system employs conventional treatment including coagulation, filtration, and disinfection with chloramines and chlorine dioxide, ensuring safe delivery throughout the service area.

The primary watershed is the Sacramento-San Joaquin Delta, a vast estuarine system formed by river sediments over Quaternary alluvium and older Tertiary marine deposits. Upstream geology features Mesozoic Franciscan Complex rocks and Cretaceous granitic intrusions that weather to release minerals, while delta sediments include shell-rich layers contributing calcium. This geology imparts a moderately mineralised character, with CCWD reporting hardness at 59–87 mg/L and magnesium at 6.4–12 mg/L, shaped by natural carbonate dissolution without extreme hardness from deep karst systems.

At moderately hard levels, scale buildup occurs on fixtures and heating elements, noticeably affecting water heaters, dishwashers, and washing machines by reducing efficiency and lifespan. Dry skin and soap scum may arise during bathing. Maintenance involves periodic vinegar descaling, installing sediment filters, and monitoring for spots on glassware. A water softener is optional but recommended if spotting or scaling is evident, especially in homes with older plumbing. Water quality scores 80/100 per recent reports and CCWD confirms 100% compliance with all applicable standards; pH is typically neutral and no specific PFAS or lead/copper violations have been noted.