Edison Water Hardness & Quality Report (2026)

New Jersey American Water (PWSID NJ1205001) operates the Edison water system, serving Edison Township in Middlesex County, New Jersey (ZIPs 08817, 08818). Water is purchased from the NJ American Raritan System, sourced from the Raritan River, Millstone River, and Delaware & Raritan Canal. Additional supply comes from Middlesex Water Company, also drawing from these rivers. Treatment occurs at upstream facilities including the Raritan-Millstone and Bridgewater plants, with an average daily supply of 6 million gallons distributed through local infrastructure.

The Raritan River Basin spans 1,100 square miles across central New Jersey, draining Triassic-Jurassic Brunswick Formation red beds and Watchung basalt flows in the Piedmont region. Glacial outwash and alluvium overlie the fractured bedrock, influencing ion leaching into rivers. Natural dissolution from mafic and felsic rocks combined with silicate and carbonate weathering yields moderately mineralized surface water — harder than softer upland reservoir sources but softer than groundwater from limestone-bearing coastal plain aquifers to the south.

Moderately hard water in Edison promotes moderate scale buildup in pipes, heaters, and fixtures over time. Water heaters, dishwashers, washing machines, and coffee makers are most affected, with mineral deposits potentially increasing energy use by 20–30%. Annual water heater flushing, vinegar soaks for faucets, and scale-inhibiting filters are recommended maintenance steps. A water softener is advised for households noticing soap scum, dry skin, or spotting on glassware. The system complies with lead and copper rules via corrosion inhibitors; treatment includes coagulation, sedimentation, filtration, chlorination, and pH adjustment, with typical pH of 6.9–7.2.