York County, South Carolina: drinking water report. York County lies south of Charlotte, NC, home to about 290,000 residents in communities like Rock Hill,…
York County lies south of Charlotte, NC, home to about 290,000 residents in communities like Rock Hill, Fort Mill, and York. York County's water comes from the Catawba River system – the same source that feeds Charlotte. Catawba River Water Treatment Plant and Lake Wylie provide the primary supply.
The Catawba River's quality at York County is influenced by upstream activity in North Carolina, including Charlotte's treated wastewater returns and Duke Energy's coal ash legacy along the river. UCMR5 data shows low-level PFAS detections in county systems.
According to the South Carolina DHEC's 2024 monitoring data, county systems met federal standards. The cross-state watershed dynamics mean North Carolina's regulatory decisions affect South Carolina's source water quality.
York County's water quality tracks with the Catawba River's overall health, which depends partly on what happens upstream in North Carolina.
Check your water for current data. A carbon or reverse osmosis filter provides additional protection. Our water filter guide covers options. Pull your detailed report, and visit our South Carolina page for statewide data.
Drinking water is one exposure route. These federal datasets also cover York County, SC.
The EPA places York County, SC in Zone 2 - a moderate-risk category, with a predicted average indoor radon level between 2 and 4 pCi/L. Zone maps predict an area's radon potential from geology and existing indoor readings; they say nothing about a specific house. Testing is the only way to know your own level.
25% of homes in York County, SC were built before 1980, and 4% before 1950. Residential lead paint was banned in 1978, so housing age is the strongest available proxy for lead-paint exposure. This describes the county's housing stock, not any one home.
Modelled annual fine-particle pollution (PM2.5) in York County, SC averages 8 µg/m³, within the EPA's annual standard of 9 µg/m³. These are CDC modelled county estimates rather than readings from a specific monitor.
How radon zones work · Air quality by county · Lead exposure guide
Across 38 public water systems serving York County, SC with EPA lead testing on record, 4 (10.5%) reported a 90th-percentile lead result above the EPA's 15 ppb action level, and the median is 2.5 ppb. 17 water systems serving York County, SC carry a health-based EPA Safe Drinking Water Act violation.
| Most-cited violation type | Systems affected |
|---|---|
| Lead and Copper Rule Revisions | 10 |
| Lead and Copper Rule | 5 |
| Total Trihalomethanes (TTHM) | 3 |
| Total Coliform Rule | 1 |
| Revised Total Coliform Rule | 1 |
Source: EPA Lead and Copper Rule 90th-percentile tap sampling and EPA SDWIS Safe Drinking Water Act enforcement records, aggregated from the public water systems serving this county. Figures are counts of water systems, not a test of any individual home or tap.