06437
Guilford, CT
CTWC - SHORELINE REGION-GUILFORD SYSTEM

Is Guilford tap water safe to drink?

Higher concern
Last tested: September 2025
Action Advised
Source: Official EPA UCMR5 federal monitoring data | Last tested September 2025

Can you drink the tap water in Guilford?

Guilford tap water has 9 contaminants above EPA guidelines, including PFOS at 3,0× the limit (tested September 2025). See the full compound-by-compound breakdown and filter recommendations.

Recommended for Guilford tap water
Water filter for Guilford tap water: Epic Pure XP Water Filter Pitcher
Pitcher filter
Epic Pure XP Water Filter Pitcher
NSF-certified dual-layer filtration reduces 70+ contaminants including PFAS, lead, chlorine, microplastics, and bacteria.
Contaminants above EPA limits detected in Guilford. Fastest way to reduce exposure.
See certified filter on Amazon

The health risk for Guilford

PFAS ('forever chemicals') have been detected above EPA limits in this water system's most recent tests. These synthetic chemicals do not break down in the body and are linked to a range of health effects. A certified filter is strongly recommended.
  • PFBS, PFOA, PFOS, PFPeA above limit.
PFOS concentration (µg/L) September 2025
0 µg/L 0.004 µg/L 0.02 µg/L
0.012 µg/L
Detected
µg/L
0.004 µg/L
EPA limit
guideline
200% above limit
Comparison
vs. guideline
EPA limit: 0.004 µg/L | Your water: 0.012 µg/L
Certified Filters for Guilford Tap Water

PFOS (a PFAS 'forever chemical') was detected above EPA limits. These filters are independently certified to reduce common drinking-water contaminants.

Water filter recommendation for Guilford tap water: Epic Pure XP Water Filter Pitcher
Pitcher filter
Epic Pure XP Water Filter Pitcher
NSF-certified dual-layer filtration reduces 70+ contaminants including PFAS, lead, chlorine, microplastics, and bacteria.
Best for renters or quick setup. No installation needed.
See certified filter on Amazon
Water filter recommendation for Guilford tap water: Waterdrop G3P600 Reverse Osmosis System
Under-sink RO system
Waterdrop G3P600 Reverse Osmosis System
8-stage tankless RO system certified to NSF/ANSI 58, reduces 1,000+ contaminants including PFAS, lead, arsenic, fluoride, and nitrates.
Best for homeowners. Heavy-duty filtration for long-term protection.
See certified filter on Amazon
Most elevated compounds
Compound Measurement EPA Limit Comparison
PFOS
Tested: September 2024 · Weiss Well		 0.012 µg/L 0.004 µg/L 200% above limit
PFOS
Tested: October 2024 · Guilford Well		 0.009 µg/L 0.004 µg/L 125% above limit
PFOS
Tested: September 2024 · Clinton Well		 0.008 µg/L 0.004 µg/L 100% above limit
PFOA
Tested: September 2024 · Clinton Well		 0.006 µg/L 0.004 µg/L 50% above limit
PFPeA
Tested: September 2024 · Five Fields Well		 0.004 µg/L 0.003 µg/L 33% above limit
View all tested compounds

Pinewood Well · Tested: September 2024

Compound Measurement EPA Limit Comparison
PFBS 0.004 µg/L 0.003 µg/L 33% above limit
PFOA 0.005 µg/L 0.004 µg/L 25% above limit
PFOS 0.005 µg/L 0.004 µg/L 25% above limit
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Clinton Well · Tested: September 2024

Compound Measurement EPA Limit Comparison
PFOS 0.008 µg/L 0.004 µg/L 100% above limit
PFOA 0.006 µg/L 0.004 µg/L 50% above limit
PFPeA 0.003 µg/L 0.003 µg/L 100% of limit
PFBA 0.007 µg/L 6 µg/L 0.1% of limit
PFHxA 0.003 µg/L 3 µg/L 0.1% of limit
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Five Fields Well · Tested: September 2024

Compound Measurement EPA Limit Comparison
PFPeA 0.004 µg/L 0.003 µg/L 33% above limit
PFOA 0.005 µg/L 0.004 µg/L 25% above limit
PFHxA 0.004 µg/L 3 µg/L 0.1% of limit
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOS <0.004 µg/L 0.004 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Guilford Well · Tested: Multiple dates

Compound Measurement EPA Limit Comparison
PFOS 0.009 µg/L 0.004 µg/L 125% above limit
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOA <0.004 µg/L 0.004 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Weiss Well · Tested: September 2024

Compound Measurement EPA Limit Comparison
PFOS 0.012 µg/L 0.004 µg/L 200% above limit
PFOA 0.004 µg/L 0.004 µg/L 100% of limit
PFHxS 0.004 µg/L 0.01 µg/L 40% of limit
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Holbrook Well · Tested: September 2025

Compound Measurement EPA Limit Comparison
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOA <0.004 µg/L 0.004 µg/L Below limit
PFOS <0.004 µg/L 0.004 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Interconnection - CT0261031 · Tested: December 2024

Compound Measurement EPA Limit Comparison
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOA <0.004 µg/L 0.004 µg/L Below limit
PFOS <0.004 µg/L 0.004 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Interconnection - CT0930011 · Tested: June 2024

Compound Measurement EPA Limit Comparison
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOA <0.004 µg/L 0.004 µg/L Below limit
PFOS <0.004 µg/L 0.004 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

MacKenzie WTP · Tested: December 2024

Compound Measurement EPA Limit Comparison
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOA <0.004 µg/L 0.004 µg/L Below limit
PFOS <0.004 µg/L 0.004 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit

Saybrook Well · Tested: September 2024

Compound Measurement EPA Limit Comparison
lithium <9.000 µg/L 10 µg/L Below limit
HFPO-DA <0.005 µg/L 0.01 µg/L Below limit
PFNA <0.004 µg/L 0.01 µg/L Below limit
PFHxS <0.003 µg/L 0.01 µg/L Below limit
PFHxA <0.003 µg/L 3 µg/L Below limit
PFBA <0.005 µg/L 6 µg/L Below limit
11Cl-PF3OUdS <0.005 µg/L 0.005 µg/L Below limit
4:2 FTS <0.003 µg/L 0.003 µg/L Below limit
6:2 FTS <0.005 µg/L 0.005 µg/L Below limit
8:2 FTS <0.005 µg/L 0.005 µg/L Below limit
9Cl-PF3ONS <0.002 µg/L 0.002 µg/L Below limit
ADONA <0.003 µg/L 0.003 µg/L Below limit
PFBS <0.003 µg/L 0.003 µg/L Below limit
PFDA <0.003 µg/L 0.003 µg/L Below limit
PFDoA <0.003 µg/L 0.003 µg/L Below limit
PFHpA <0.003 µg/L 0.003 µg/L Below limit
PFHpS <0.003 µg/L 0.003 µg/L Below limit
PFOA <0.004 µg/L 0.004 µg/L Below limit
PFOS <0.004 µg/L 0.004 µg/L Below limit
PFPeA <0.003 µg/L 0.003 µg/L Below limit
PFTrDA <0.007 µg/L 0.007 µg/L Below limit
PFUnA <0.002 µg/L 0.002 µg/L Below limit
Primary source EPA UCMR5 (2023-2025)
Guideline source EPA PFAS drinking water standard (PFOS: 0,004 µg/L, effective 2024, compliance by 2031)
Last tested September 2025
Last page update 2026-03-31

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    Data reflects publicly reported utility records from EPA datasets and local utility disclosures. This information is educational and not medical advice.

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