WaterVerge

Is Ashburn, VA Tap Water Safe to Drink?

Graded A-, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

335K residents served 1 water system PWSID: VA6107350
Overall Score
87 / 100
Violations
3 active
Last Updated
May 2026
Source
Surface water
#95 of 230 in Virginia Top 27% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
87/100
waterverge.com
A- 87/100

Ashburn, VA — Water Quality Report

Ashburn's drinking water received a grade of A- (87 out of 100), indicating good water quality. The city's 1 water system serves approximately 334,808 residents using surface water.

Lead levels were measured at 0.5 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 14 violations on record, including 2 health-based violations. 3 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Ashburn's water

Ashburn ranks #95 out of 230 cities in Virginia for water quality, placing it mid-range in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.20 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

Quality Breakdown

Water quality score

See methodology →
87 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
42.5/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.5 ppb (90th percentile).
Contaminants
15.5/20
B
1 PFAS compound detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Surface water.
Water Safety

Is Ashburn, VA water safe to drink?

Concerns Identified

Ashburn's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (87/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 334,808 residents using surface water (rivers, lakes, or reservoirs).

3
Active Violations
0.5 ppb
Lead (90th %ile)
1 compound
PFAS Detected
6 events
Disaster History

Recent water quality updates for Ashburn

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Ashburn's water quality assessment. Grade: A- (87/100).

Violation
1 drinking water violation recorded

Contaminants: Lead and Copper Rule.

Disaster
HURRICANE FLORENCE

Federal disaster declaration (FEMA DR-3403). Hurricane event — may have impacted local water infrastructure.

Disaster
HURRICANE SANDY

Federal disaster declaration (FEMA DR-4092). Hurricane event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Stage 2 Disinfectants and Disinfection Byproducts Rule.

Key contaminant findings

Based on the most recent EPA sampling data for Ashburn's water supply.

Lead Within Limits
Detected: 0.5 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: PFPeA at 0.0034 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Ashburn's water system has 14 total violations on record, including 2 health-based violations. 3 remain unresolved. 1 violation was issued in the last 5 years.

MRMCL
Most recent violations:
Oct 2023 Lead and Copper Rule Open
Jan 2009 Stage 2 Disinfectants and Disinfection Byproducts Rule Open
Jul 2001 Lead and Copper Rule Resolved
Dec 1993 Coliform (TCR) Resolved
Feb 1993 Coliform (TCR) Resolved

Flood & environmental risk

Loudoun County has experienced 6 federally declared disasters since 1996. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include S F Catoctin Creek, Limestone Branch, Goose Creek, Potomac River, Broad Run.

HURRICANE FLORENCE
Hurricane FEMA DR-3403
HURRICANE SANDY
Hurricane FEMA DR-4092
HURRICANE SANDY
Hurricane FEMA DR-3359

Where does Ashburn's water come from?

Ashburn's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 334,808 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include S F Catoctin Creek (river), Limestone Branch (river), Goose Creek (river), Potomac River (river), Broad Run (river).

What Ashburn residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Ashburn's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Ashburn's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.5 ppb
EPA Action Level: 15 ppb · 3% of limit
Safe Level
PFPeA
PFAS / Forever Chemical
Near MCL
0.0034 µg/L
EPA MCL: 0.004 µg/L · 85% of limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
9.3 µg/L
EPA MCL: 60 µg/L · 16% of limit
Within LimitUCMR 4 DataHAA6Br: 7.0 µg/LHAA9: 15.3 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.20 µg/L
CA MCL (no federal MCL): 10 µg/L · 2% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
180.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 12% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
4.2 µg/L
EPA Secondary MCL: 50 µg/L · 8% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
0.64 µg/L
EPA Short-term HA: 21 µg/L · 3% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Elevated
200.0 µg/L
EPA Lifetime HA: 210 µg/L · 95% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Elevated
24.00 µg/L
EPA Lifetime HA: 40 µg/L · 60% of limit
DetectedUCMR 3 Data
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

14
Total violations
2
Health-based
3
Active / unresolved
Oct 2023
Most recent violation
Compliance Record

Violations & advisories

14 Total
3 Active
2 Health-based
11 Resolved
Violations by category
Inorganic Chemicals
6
Lead and Copper Rule
2
Total Coliform Rule
2
Stage 2 Disinfectants and Disinfection Byproducts Rule
1
Arsenic Rule
1
Oct 2023 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jan 2009 Active
Stage 2 Disinfectants and Disinfection Byproducts Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Jul 2001 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2001
Dec 1993 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Dec 1993
Feb 1993 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Feb 1993
Dec 1984 Resolved
Mercury
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Selenium
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Barium
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Fluoride
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Chromium
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Dec 1984 Resolved
Cadmium
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 1987
Industrial pollution

Top industrial polluters within 10 miles of Ashburn

Industrial polluters nearby

Reported releases to surface water by facilities near Ashburn, ranked by pounds discharged annually.

Total reported releases to surface water: 821 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
VIRGINIA CONCRETE DULLES PLANT
Nonmetallic Mineral Product · VULCAN MATERIALS CO
STERLING, VA20166
Nitrate compounds (water dissociable; reportable only when in aqueous solution)2963.2 mi
SUPERIOR CONCRETE MATERIALS INC. - DULLES
Nonmetallic Mineral Product · SMYRNA READY MIX LLC
CHANTILLY, VA20152
Nitrate compounds (water dissociable; reportable only when in aqueous solution)2887.5 mi
VIRGINIA CONCRETE COCHRAN MILL
Nonmetallic Mineral Product · VULCAN MATERIALS CO
LEESBURG, VA20175
Nitrate compounds (water dissociable; reportable only when in aqueous solution)1454.4 mi
VIRGINIA CONCRETE CO INC-CHANTILLY
Nonmetallic Mineral Product · VULCAN MATERIALS CO
CHANTILLY, VA20152
Nitrate compounds (water dissociable; reportable only when in aqueous solution)927.3 mi
TITAN VIRGINIA READY-MIX LLC-STERLING PLANT
Nonmetallic Mineral Product · TITAN AMERICA LLC
STERLING, VA20166
Lead03.4 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Ashburn

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Drought conditions

D2 — severe drought

Loudoun County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

3
Weeks at D2+ (current streak)
14.5%
Months in D2+ (last 30y)
6
Weeks at D2+ (last 5y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

6
Declared disasters
Sep 2018
Most recent
Hurricane
Most common type

Loudoun County has experienced 6 federally declared disasters since 1996. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2018
HURRICANE FLORENCE
Hurricane FEMA #3403
Nov 2012
HURRICANE SANDY
Hurricane FEMA #4092
Oct 2012
HURRICANE SANDY
Hurricane FEMA #3359
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3240
Sep 2003
HURRICANE ISABEL
Hurricane FEMA #1491
Jan 1996
FLOODING, HIGH WINDS, AND WIND DRIVEN RAIN
Flood FEMA #1098

Recommended water filters

Based on contaminants detected in Ashburn's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.5 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium ND HI µg/L PFAS Not Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA 0.003 HI µg/L PFAS Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 14.5 ppb from 1992 (15.0 ppb) to 2026 (0.5 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Surface Water
Operator
Local Government
Population Served
334,808
Water Systems
1
Water Source

Where Ashburn's water comes from

Surface Water

Ashburn's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by local government ownership and serves approximately 334,808 people through 1 water system.

Local Hydrology

Water bodies near Ashburn

Ashburn is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

S F Catoctin Creek
river
Limestone Branch
river
Goose Creek
river
Potomac River
river
Broad Run
river
Infrastructure

Water systems serving Ashburn

System Name PWSID Population Source
LOUDOUN WATER - CENTRAL SYSTEM VA6107350 334,808 SW
Regional Comparison

How Ashburn compares

Full Virginia rankings →

Ashburn's score of 87/100 is above the average of 80/100 among major Virginia cities. It outscores 7 of 10 nearby cities.

Ashburn (this city)
87
Herndon
75.5
Henrico
92.8
Virginia avg
80
City Profile

About Ashburn, VA

Wikipedia →

Ashburn is an unincorporated settlement and census-designated place (CDP) in Loudoun County, Virginia, United States. At the 2020 United States census, its population was 46,349, up from 3,393 in 1990. It is 30 miles (48 km) northwest of Washington, D.C., and part of the Washington metropolitan area. Ashburn is a major hub for Internet traffic due to its many data centers.

Economic Profile
$147,192
Median Income
$618,435
Median Home Value
$2,266/mo
Median Rent
2.7%
Unemployment
Community
40.9
Median Age
1,148
People / sq mi
65%
College Educated
69.1%
Homeownership
Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail

Frequently asked questions

Is Ashburn, VA tap water safe to drink?

Ashburn's water quality earned a grade of A- (87/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #95 out of 230 cities tested in Virginia.

What contaminants are in Ashburn's water?

Lead was measured at 0.5 ppb (90th percentile). 1 PFAS compound was detected. 14 violations are on record.

How is Ashburn's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Ashburn?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Ashburn's water come from?

Ashburn's water is sourced from Surface water. The city has 1 water system serving approximately 334,808 residents.

What health violations has Ashburn's water system had?

Ashburn has 2 health-based violations on record. The most recent violation was recorded in October 2023. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.

How does Ashburn's water compare to other cities?

Ashburn ranks #95 out of 230 cities in Virginia (better than 59% of state cities) and #4287 out of 15744 cities nationally (73th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.