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Dakota County, MN Water Quality

Water quality data for 17 public water systems serving Dakota County, Minnesota — based on EPA SDWIS enforcement records, lead testing results, and health-based violation history.

📅 2026 Report 🔄 Data updated 2026 Q2 📍 17 water systems · 29 cities
✅
Excellent — All Systems Performing Well

Water quality across the county is outstanding with minimal violations and very low lead levels.

A

Dakota County Earns a A

Dakota County: 29 communities across 17 water systems. 100.0% have no open violations.

  • Median lead where detected: 3.00 ppb
  • 17 communities with a lead detection, 12 reporting none detected
  • 3 communities with PFAS above the federal limit
  • 2 with significant inspection deficiencies
  • 100.0% of communities have no open violations
3 ppb
Median Lead Level
County-wide, 90th percentile
17
Water Systems
Active CWS & NTNCWS
100%
Violation-Free
No active violations on record
How we grade counties: MyWaterIQ uses EPA SDWIS enforcement data — actual MCL violations and lead test results — not the aspirational MCLG targets used by some sites. A grade reflects real compliance history, not theoretical risk. Learn more →

Cities by Water Quality

⭐ Best Performing
  • Waterford
    3.00 ppb
    No federal limits exceeded on record
    A
  • Greenvale
    3.00 ppb
    No federal limits exceeded on record
    A
  • Eureka
    Not detected
    No federal limits exceeded on record
    A
  • Eagan
    Not detected
    No federal limits exceeded on record
    A
  • Lakeville
    Not detected
    No federal limits exceeded on record
    A
⚠ Needs Attention
  • Marshan
    3.00 ppb
    PFAS above the limit at 4 of 5 sampling points
    C
  • Hastings
    3.00 ppb
    PFAS above the limit at 4 of 5 sampling points
    C
  • Nininger
    3.00 ppb
    PFAS above the limit at 4 of 5 sampling points
    C
  • South St. Paul
    8.00 ppb
    5 health-based violations since 2015
    B
  • Inver Grove Heights
    3.00 ppb
    18 health-based violations since 2015
    B
County Lead Level — Median 3 ppb
Based on most recent 90th percentile lead tests across all reporting systems
0 ppb5 ppb10 ppb15 ppb
County median: 3 ppb — 20% of the federal action level
Systems by Lead Level
Under 5 ppb
11
5 – 10 ppb
6
No Data
12

All Cities in Dakota County

Eagan Not detected A
Lakeville Not detected A
Burnsville Not detected A
Apple Valley Not detected A
Inver Grove Heights 3.00 ppb B
Rosemount 3.00 ppb A
Farmington Not detected A
Hastings 3.00 ppb C
West St. Paul 8.00 ppb B
South St. Paul 8.00 ppb B
Mendota Heights 8.00 ppb B
Empire Not detected B
Hampton Not detected B
Lilydale 8.00 ppb B
Sunfish Lake 8.00 ppb B
Randolph Not detected B
Vermillion 4.00 ppb B
Randolph Not detected B
Mendota 8.00 ppb B
New Trier 1.00 ppb B
Vermillion Not detected B
Castle Rock Not detected A
Coates 3.00 ppb A
Hampton 1.00 ppb B
Nininger 3.00 ppb C
Marshan 3.00 ppb C
Eureka Not detected A
Waterford 3.00 ppb A
Greenvale 3.00 ppb A
Showing 29 cities
No active violations Active violations

About Dakota County Drinking Water

Dakota County is served by 17 water systems covering 29 communities. No community here has an open violation on record.

Of the communities reporting lead results, 17 recorded a detection, with a median of 3.00 ppb — 20% of the federal action level. 12 reported none detected, which means below the laboratory limit rather than an absence of lead.

3 of 29 communities have PFAS above the limits EPA set in 2024, measured as a running annual average at each sampling point. State inspectors recorded significant deficiencies at 2 of them.

Frequently Asked Questions

Is Dakota County tap water safe to drink?▼
No community in Dakota County has an open violation on record. 3 of 29 have PFAS above the federal limit, which is the main open concern.
What is the lead level in Dakota County?▼
Among communities with a detection the median is 3.00 ppb, 20% of the 15 ppb action level. 12 reported none detected and 0 reported no result.
How many water systems serve Dakota County?▼
17 community water systems serve 29 communities here.
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