waterbycounty
Compiled federal source snapshot

North Carolina Water Quality

Drinking water data for all 100 counties.

Avg SDWIS Compliance Index

52.1

Most Common Five-Year SDWIS Compliance Band

C

Counties with Data

100

of 100 total

County water atlas

North Carolina water signals by county

A state-level 2.5D view across drinking-water compliance, watershed impairment, monitoring density, and streamflow snapshot context. Pin any county, switch layers, then use the lens controls to compare index ranges, recorded violation rates, or impaired watersheds without leaving the page.

Counties

100

Avg SDWIS index

52.1

Watersheds

3

ATTAINS counties

Monitoring

100

72 fresh USGS snapshots

State atlas layers combine EPA SDWIS health-based violations, EPA ATTAINS 303(d) impairment assessments, EPA Water Quality Portal monitoring sites, and representative USGS NWIS streamflow gauges. Streamflow values appear only for fresh pipeline snapshots, not as a continuously updated stream. County pages include the observation time and year.

Prepared by ByCounty Editorial TeamPublished by WaterByCounty

Multi-source coverage in North Carolina

Beyond Drinking Water

EPA SDWIS

100/ 100

counties with drinking-water compliance data

666 health violations statewide (5yr)

EPA ATTAINS

0.0%

avg impaired across 3 counties

0 of 3 assessed bodies impaired

EPA WQP

1,909

monitoring sites across 100 counties

662,217 total readings (5yr window)

USGS NWIS

72

counties with a fresh pipeline snapshot

11 above60 below

State atlas notes

What stands out in North Carolina

County water quality is not one number. The strongest read comes from comparing drinking-water compliance against watershed impairment, monitoring density, and streamflow context. Use these signals as a starting point, then open any county profile for source-level detail.

Compliance spread

Alexander County has the highest value in the published state SDWIS Compliance Index table at 86.2/100, while Caswell County has the lowest at 3.2/100. That is a 83.0 point gap inside one state.

Zero health violations

14

3+ health violations

62

Watershed pressure

The atlas impairment layer points to counties where assessed water bodies are most likely to miss state quality standards. Assessment density varies, so compare the percentage with the number of assessed bodies on the county page.

Hertford County0.0%Northampton County0.0%Warren County0.0%

Monitoring hubs

Wake County98 sitesBrunswick County66 sitesCarteret County62 sites

Lowest flow reads

Brunswick County0%Person County2%Durham County3%

Highest fresh streamflow pipeline snapshots: Cabarrus County (677%, observation 2026), Wilkes County (133%, observation 2026), Haywood County (130%, observation 2026). These are source-data observations, not household tap-water conclusions.

All North Carolina Counties

CountySDWIS Compliance Index
Alexander County86.2
Alleghany County86.2
Camden County86.2
Dare County86.2
Davidson County86.2
Forsyth County86.2
Gates County86.2
Graham County86.2
Hyde County86.2
Lenoir County86.2
Madison County86.2
Pasquotank County86.2
Person County86.2
Yancey County86.2
Mecklenburg County72.3
Durham County71.7
Brunswick County71.5
Union County71.2
New Hanover County68.5
Harnett County68.2
Lincoln County67.4
Cumberland County65.9
Craven County64.8
Sampson County63.8
Currituck County63.6
Iredell County63.3
Guilford County62.6
Wayne County62.6
Hoke County61.9
Granville County61.6
Onslow County61.6
Pitt County61.6
Catawba County61.1
Cleveland County61.0
Beaufort County60.5
Orange County59.6
Halifax County59.3
Pamlico County58.6
Carteret County57.8
Caldwell County57.3
Lee County57.3
Bertie County56.9
Burke County56.9
Alamance County56.7
Wake County55.4
Scotland County52.3
Robeson County52.2
Wilkes County51.1
Jones County50.3
Hertford County49.3
Buncombe County48.7
Davie County48.3
Rowan County48.1
Stokes County47.4
Chowan County47.1
Nash County47.1
Henderson County46.9
Franklin County46.8
Rutherford County46.7
Haywood County46.4
Gaston County46.1
Anson County46.0
Surry County45.6
Johnston County45.4
Bladen County44.5
Chatham County43.8
Mitchell County43.5
Columbus County42.8
Randolph County42.8
Duplin County41.8
Polk County40.1
Stanly County40.1
Cabarrus County39.4
Swain County39.1
Wilson County39.0
Cherokee County38.3
Perquimans County38.0
Greene County36.8
Tyrrell County35.0
Martin County34.6
Vance County34.5
Yadkin County33.6
Rockingham County33.3
Washington County33.3
Moore County31.7
Richmond County31.0
Watauga County30.8
Northampton County29.7
Jackson County26.9
Clay County26.8
Warren County26.7
Edgecombe County25.6
Transylvania County25.5
Pender County24.1
Macon County23.9
Avery County20.2
Ashe County16.8
McDowell County14.1
Montgomery County12.8
Caswell County3.2

Frequently Asked Questions

Which North Carolina county has the highest SDWIS Compliance Index?
Alexander County has the highest SDWIS Compliance Index in the published North Carolina cohort at 86.2/100. This WaterByCounty relative comparison is not an EPA score and does not establish current conditions for a utility or address.
What does the Five-Year SDWIS Compliance Band mean?
The band is derived only from each county aggregation's recorded health-violation rate per 100,000 people served for the stated five-year source window. It is separate from the relative SDWIS Compliance Index and is not a current determination for a specific utility or address.
What does EPA ATTAINS report across North Carolina?
Across 3 published North Carolina county records with EPA ATTAINS data, 0 of 3 assessed water bodies are listed as impaired. This is a watershed assessment and does not describe finished household tap water.
Which USGS streamflow records are shown across North Carolina?
WaterByCounty has 72 fresh USGS pipeline snapshots in the published North Carolina cohort. Each county page shows its observation timestamp and year. A pipeline snapshot is not a continuously updated reading or a tap-water safety measure.
Where can North Carolina residents find current official information?
Review the applicable utility's Consumer Confidence Report, active notices, and the state drinking-water agency. WaterByCounty's county-level historical aggregations do not establish the current status of a specific utility, address, private well, or household plumbing system.
What does Water Quality Portal monitoring volume show in North Carolina?
The published county records contain 662,217 results from 1,909 monitoring locations in the site's five-year aggregation. Monitoring volume does not by itself indicate better or worse water quality.

Data Sources

Drinking-water compliance data from the EPA Safe Drinking Water Information System (SDWIS) via the ECHO enforcement database. The WaterByCounty SDWIS Compliance Index reflects the recorded rate and is not an EPA score.

Disclaimer: This data is informational only. It is not health, legal, or professional advice. For concerns about your specific water supply, contact your local water utility.

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