Frankfort Water Hardness & Quality Report (2026)

Frankfort Plant Board supplies drinking water to the City of Frankfort and surrounding areas in Franklin County, Kentucky, serving as the primary utility for the state capital. Water is sourced from surface water in Pool #4 of the Kentucky River, created by Lock and Dam No. 4, and treated at the Frankfort Plant Board treatment facility. The supply serves residential, commercial, and governmental users in the capital region, with the utility maintaining compliance with state and federal standards through regular monitoring.

The Kentucky River watershed encompasses approximately 7,000 square miles across central Kentucky, flowing through the karst landscape of the Inner Bluegrass physiographic region. Key geological features include Ordovician limestone formations such as the Lexington Limestone and Clays Ferry Formation, interbedded with shales from the Bluegrass Region, which weather and release calcium and magnesium into surface waters. River water integrates groundwater seepage from underlying carbonate aquifers, and prolonged contact with these Paleozoic carbonates imparts a hard water character dominated by carbonate dissolution.

Very hard water in Frankfort leads to significant scale buildup in water heaters, dishwashers, washing machines, and plumbing fixtures, reducing efficiency and lifespan. Glassware spotting and diminished soap lathering are common. Regular vinegar-based descaling, installing sediment filters, and using a water softener are recommended to protect infrastructure and reduce maintenance. Recent testing shows an overall water score of C+, with eight contaminants exceeding health guidelines including arsenic from natural geological sources, total chromium, and disinfection byproducts such as monochloroacetic acid and dibromoacetic acid. The utility treats river water via coagulation, sedimentation, filtration, and chlorination, meeting EPA legal limits.