2 community water systems serve or are based in ZIP 21663. Showing Town Of St. Michaels, the largest by reported population served. The other systems are summarized below.
- System name
- Town Of St. Michaels
- EPA PWS ID
- MD0200006
- Location
- St Michaels, MD
- Population served
- 2,650
- Water source
- Ground water
- Primary EPA source
- EPA ECHO record for MD0200006
Make sure this is the system tied to your address before using these results to make a decision about your own water. A ZIP code is not a street address.
EPA lab monitoring (UCMR 5)
EPA has no UCMR 5 (PFAS and lithium) monitoring results on file for this system.
UCMR 5 results are monitoring data, not a compliance determination. PFAS compliance is governed by separate EPA drinking-water rules. Some PFAS rule changes are proposed for 2026 — see what's proposed.
Lead at customer taps
Lead at sampled customer taps, 90th percentile (Jan. 2023–Dec. 2025): 1.8 ppb. EPA's current action level is 15 ppb; its health goal (MCLG) is 0.
Lead is regulated with an action level rather than a standard MCL. EPA's lead action level is 15 ppb today; the Lead and Copper Rule Improvements lower it to 10 ppb starting Nov. 1, 2027.
Violations on the federal record
The EPA record shows 11 violations, 3 health-based.
| Type | Rule / contaminant | Since |
|---|---|---|
| Record · missed required testing or reporting | — | 2008 |
| Record · missed required testing or reporting | Lead & Copper Rule | 2002 |
| Record · missed required testing or reporting | Lead & Copper Rule | 2014 |
| Record · other violation | Surface Water Treatment | 2012 |
| Record · missed required testing or reporting | Lead & Copper Rule | 2017 |
| Record · missed required testing or reporting | Arsenic | 2018 |
| Record · other violation | Surface Water Treatment | 2021 |
| Record · other violation | Surface Water Treatment | 2021 |
| Health-based · exceeded a contaminant limit | Arsenic | 2022 |
| Health-based · exceeded a contaminant limit | Arsenic | 2022 |
| Health-based · exceeded a contaminant limit | Arsenic | 2022 |
Other systems serving or based in ZIP 21663
| System | EPA PWS ID | People served | Violations |
|---|---|---|---|
| Martingham Utilities Cooperative | MD0200004 | 675 | 1 |
On a private well? EPA public-system data does not describe your individual well. Test your water directly.
What the numbers mean
EPA uses two different benchmarks: the legal limit (MCL) and the health goal (MCLG). They are not always the same number. Read EPA's explanation →
Open the interactive report →What the government says
Sources: U.S. EPA SDWIS (system record and violations, queried live) · EPA SDWIS lead & copper 90th-percentile results. EPA data can lag the latest tests.