Lake Caroline
What EPA’s and CDC’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.
- Serves
- 2,933 people
- Connections
- 1,173
- Water source
- Surface water
- Based in
- Rockville, VA
- County
- Caroline
- Owner
- Private
The ZIP code it serves
The short answer
Nothing in EPA’s and CDC’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.
What was found
Arsenic: Virginia’s yearly averages per water system, as CDC’s Environmental Public Health Tracking Network publishes them, 2021 to 2023.
Total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, chromium (total) and nitrate: EPA’s compliance monitoring file, samples taken from Sept. 4, 2013 to Aug. 20, 2019. Newer results are in the utility’s annual water quality report.
Below EPA’s limits3
Total trihalomethanes (TTHM)
Forms or is added in treatment
43.6ppb
Highest yearly average, 2013 to 2019
2019, one sample: 16.7 ppb
Averaged by year, the highest was 43.6 ppb, in 2014, below EPA’s legal limit of 80 ppb. Its highest single sample was 62.2 ppb. In 2019, the latest year on file, its one sample was 16.7 ppb.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
Haloacetic acids (HAA5)
Forms or is added in treatment
7.8ppb
Highest yearly average, 2013 to 2019
2019: not found
Averaged by year, the highest was 7.8 ppb, in 2016, below EPA’s legal limit of 60 ppb. Its highest single sample was 13.4 ppb. In 2019, the latest year on file, it wasn’t found in its one sample.
What handles it
No certification claim covers this compound yet.
Fluoride
Forms or is added in treatment
0.37ppm
Highest yearly average, 2016 to 2019
2019, one sample: 0.2 ppm
Averaged by year, the highest was 0.37 ppm, in 2016, below EPA’s legal limit of 4.0 ppm. In 2019, the latest year on file, its one sample was 0.2 ppm.
What handles it
- NSF/ANSI 58 look for “Fluoride Reduction”
- NSF/ANSI 53 look for “Fluoride”
4 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Arsenic
- Chromium (total)
- Lead
- Nitrate
Violations since 2016
No health-based violations on file with EPA since 2016.
What this report can’t tell you
Everything else. Arsenic results here are Virginia’s yearly averages as CDC publishes them, from 2021 on, with EPA’s national file for 2012 to 2019. Total trihalomethanes (TTHM), haloacetic acids (HAA5), fluoride, chromium (total) and nitrate come from EPA’s file alone, which ends in 2019. Lake Caroline’s own annual report, which it must send you every year, has newer results for those and the contaminants this page does not show.
Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.
What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.
Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; CDC’s yearly averages for Virginia cover 2021 to 2023; EPA’s compliance samples are from Sept. 4, 2013 to Aug. 20, 2019.
Testing your own tap
The 3 labs Virginia certifies closest to the area Lake Caroline serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Matthews Well & Pump Inc.
Glen Allen, VA · about 18 miles
Certified for bacteria
Spotsylvania County Laboratory Services
Fredericksburg, VA · about 19 miles
Certified for bacteria, nitrate, minerals and other inorganics
Oakwood Scientific Laboratory
Mechanicsville, VA · about 19 miles
Certified for bacteria
Virginia Household Water Quality Program, Virginia Cooperative Extension: Drinking water clinics in about 70 counties a year, run through local Extension offices: pick up a kit, collect the sample on the set day, and drop it off locally. Each kit tests well, spring or cistern water for 28 things, including bacteria, nitrate, lead and arsenic. $70 a kit, with funding to help if you need it. Virginia Household Water Quality Program.
All 145 certified labs for VirginiaSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- CDC Environmental Public Health Tracking Network, yearly averages Virginia supplied to CDC, 2021 to 2023, read Oct. 8, 2026. TapBuff’s comparisons with EPA’s limits are its own, not CDC’s or Virginia’s.
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Certified labs: DCLS, drinking water laboratories with certification detail, read Oct. 10, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID VA6033425. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Nothing here is above a health goalIn EPA’s and CDC’s records for this utility. They don’t cover everything, which is why the next step matters.Every contaminant TapBuff tracks
- Get the utility’s own reportLake Caroline must send you a water quality report every year. It covers contaminants this page does not show, and has newer results than EPA’s national file for the ones here that come from it.How to read it
- Test your own tap for leadYour service line, solder and fixtures decide the lead at your faucet, not the utility’s average.Lead in your water: what to do
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded