EPA data as of Oct 2026 · page updated 2026-10-30

Winterthur

Winterthur (EPA ID DE0000503) in Winterthur, DE supplies groundwater (wells) to about 687 people: no health-based violations since 2016, latest lead result 12 ppb, PFAS not tested.

System facts

People served687
Connections39
Sourcegroundwater (wells)
WholesalerNo

Health-based violations

No health-based violations reported since 2016.

Lead

Jan 202212 ppb
Jan 20190 ppb
Jan 20161.4 ppb
Jan 20130 ppb
Jan 20100 ppb
Jan 20076 ppb
Jan 19962 ppb
Jan 19953.5 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5).

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions

Has Winterthur had drinking water violations?

No health-based violations reported since 2016.

What is the lead level in Winterthur water?

The latest 90th-percentile lead result (Jan 2022) was 12 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).

Does Winterthur have PFAS in its water?

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5 covers systems serving over 3,300 people and a sample of smaller ones).