Mercer County, New Jersey: drinking water report. Mercer County – Trenton and Princeton – serves about 380,000 residents.
Mercer County – Trenton and Princeton – serves about 380,000 residents. Trenton Water Works draws from the Delaware River, while other communities are served by New Jersey American Water or Elizabethtown Water Company using groundwater and purchased surface water. The county sits at the fall line where the Piedmont meets the Coastal Plain, creating different geological water quality profiles across relatively short distances.
New Jersey's strict PFAS standards apply across Mercer County. UCMR5 data shows detections in several county systems. The county's mix of governmental, industrial, and military land uses – including Joint Base McGuire-Dix-Lakehurst to the south in Burlington County, whose contamination plume extends northward – creates potential PFAS exposure pathways.
According to the New Jersey DEP's 2024 compliance data, two Mercer County water systems required treatment to meet state PFAS MCLs. Trenton Water Works' Delaware River source carries PFAS from upstream discharges, though treatment reduces levels.
New Jersey's regulatory framework means utilities are actively treating for PFAS. Household filtration adds another layer of protection.
Check your water for data specific to your provider. Our water filter guide covers which home systems complement utility treatment. Pull your detailed report, and visit our New Jersey page for statewide context.