Home › Cities › CT › Darien

Lead service lines in Darien, CT

Search 7,248 service line records published by 2 water utilities for Darien.

Your address is matched in your browser and never sent to our server.

Service line status in Darien

21Lead
0.3%
5Galvanized requiring replacement
0.1%
3,031Lead status unknown
41.8%
4,185Non-lead
57.7%
6Not classified
0.1%

Counts are records in the utilities' published inventories (not people or buildings). One property can have more than one service line record.

PFAS in Darien drinking water

Aquarion Water Company of Connecticut runs 3 public water systems connected with Darien (CT0150011, CT0350011, CT1350011); 3 have UCMR 5 results. We can't tell from the inventory which one serves a given address.

Aquarion Water Co of CT-Main System PWSID CT0150011

PFOA (highest result)
10.9 ppt above 4.0 ppt
PFOS (highest result)
6.6 ppt above 4.0 ppt
Other PFAS detected
PFBA 7.6 ppt, PFHxA 7.4 ppt, PFPeA 6.7 ppt, PFBS 4.1 ppt, PFHpA 3.9 ppt
PFAS detected
7 of 29 tested
Sampled
15 sample event(s), 5 sampling point(s), 2023-01-17 to 2024-02-20

Lead service line data on this page: Aquarion Water Company of Connecticut.

Aquarion Water Co of CT-Noroton System PWSID CT0350011

PFOA (highest result)
5.8 ppt above 4.0 ppt
PFOS (highest result)
Not detected (below the 4 ppt reporting level)
Other PFAS detected
PFBA 5.5 ppt, PFHxA 3.7 ppt, PFPeA 3.3 ppt
PFAS detected
4 of 29 tested
Sampled
10 sample event(s), 2 sampling point(s), 2023-01-19 to 2023-10-12

Lead service line data on this page: Aquarion Water Company of Connecticut.

Aquarion Water Co of CT-Stamford PWSID CT1350011

PFOA (highest result)
4.3 ppt above 4.0 ppt
PFOS (highest result)
Not detected (below the 4 ppt reporting level)
Other PFAS detected
PFPeA 3.1 ppt, PFHxA 3 ppt
PFAS detected
3 of 29 tested
Sampled
10 sample event(s), 2 sampling point(s), 2025-03-05 to 2025-12-15

Lead service line data on this page: Aquarion Water Company of Connecticut.

South Norwalk Electric & Water PWSID CT1030021

PFOA (highest result)
Not detected (below the 4 ppt reporting level)
PFOS (highest result)
Not detected (below the 4 ppt reporting level)
Other PFAS detected
none
PFAS detected
0 of 29 tested
Sampled
4 sample event(s), 1 sampling point(s), 2024-09-09 to 2025-06-04

Lead service line data on this page: South Norwalk Electric & Water (SNEW).

UCMR 5 is a one-time EPA monitoring program, not a compliance determination. The values shown are the highest single sample result at any of the system's sampling points; one result above 4.0 ppt does not mean the system violates the PFAS rule, which is judged on running annual averages under separate compliance monitoring. Results describe the public water system, not an individual home.

In April 2024 EPA set enforceable limits (MCLs) of 4.0 ppt each for PFOA and PFOS, plus 10 ppt for PFHxS, PFNA and HFPO-DA (GenX) and a Hazard Index for mixtures, with compliance based on a running annual average at each sampling point and due in 2029 (EPA ↗). In May 2026 EPA proposed letting systems request two more years for PFOA/PFOS (to April 2031) and rescinding the PFHxS, PFNA, GenX and Hazard Index limits (EPA: extension proposal ↗ · EPA: rescission proposal ↗). These are proposals, not final rules, as of the date this page was built.

Source: EPA UCMR 5 final occurrence data (EPA page last updated 2026-08-28; samples collected January 2023 – December 2025) ↗. All PFAS results nationwide →

Flood insurance claim history in Darien

NFIP community: DARIEN, TOWN OF (community ID 090005).

628NFIP claims since 1978
500claims with a payment
$21,970,772total paid

Claims by decade

DecadeClaimsPaid
1970s25$57,694
1980s50$99,652
1990s125$1,756,729
2000s88$2,307,975
2010s246$14,280,200
2020s94$3,468,523

Top flood years (by amount paid)

YearClaimsPaidFEMA event name
2012159$12,652,980Hurricane Sandy
202187$3,423,154Hurricane Ida
200756$1,654,496—

Data covers losses from 1978 to 2024 (claims data as of 2026-09-07).

Historical statistics only. Counts cover claims filed under National Flood Insurance Program policies for properties in the NFIP community “DARIEN, TOWN OF” (community ID 090005); they do not include uninsured damage or private flood insurance, and FEMA's data does not identify individual properties. Paid amounts are FEMA's building, contents and Increased Cost of Compliance payments as reported, not adjusted for inflation. This site is not an insurance agent, broker or advisor, and this is not a flood zone determination. For official flood maps, see the FEMA Flood Map Service Center.

Sources: Federal Emergency Management Agency (FEMA), OpenFEMA Dataset: NFIP Redacted Claims - v3 (API endpoint; data refresh 2026-09-09), retrieved 2026-10-08; OpenFEMA Dataset: NFIP Community Status Book - v1 (API endpoint), retrieved 2026-10-08. Used under the OpenFEMA terms and conditions.

This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).

Data sources

Streets with the most lead or GRR records

StreetLeadGalvanized requiring replacementLead status unknownNon-lead
Park Pl50166
Mansfield Ave0220105
Allen Oneill Dr20037
Chester Rd20125
Christie Hill Rd201616
Oak Shade Ave20136
Boston Post Rd10151172
Davis Ln0126
Prospect Ave01147
Herman Ave10912
Middlesex Rd1013138
Robinson St1062
Nearwater Ln014323
Locust Hill Rd10725
Lakeside Ave1056

What to do next

  1. Confirm with your utility. Inventories change as lines are inspected and replaced. The utility's official map and customer service line are the authoritative source.
  2. If your status is unknown, many utilities ask customers to report what they see where the water pipe enters the building. EPA's Protect Your Tap guide explains how to check.
  3. Consider testing. EPA: “Since you cannot see, taste, or smell lead dissolved in water, testing is the only sure way of telling whether there are harmful quantities of lead in your drinking water.” Your utility or state health department can point you to certified laboratories.
  4. Use cold water. EPA: “Use only cold water for drinking, cooking and making baby formula. Remember, boiling water does not remove lead from water.”
  5. Filters. EPA: “If you use a filter, make sure you use a filter certified to remove lead.” See EPA's consumer tool for filters certified to reduce lead.
Disclaimer: Information is copied from the utility's published service line inventory and may be incomplete, out of date, or contain errors. It is not a substitute for water testing and does not describe interior plumbing. Contact your water utility for the official status of your service line. Health information is limited to quotations from EPA and CDC.