Public water system · PA1461065
ActiveMerck and Co Inc.
At a glance
Merck and Co Inc. (PWSID PA1461065) is an active non-transient non-community water system in Montgomery County, Pennsylvania. It reports serving 8,550 people through 1 service connection. Its primary water source is purchased surface water, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in March 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
8,550
Service connections
1
Primary source
SWP
Purchased surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Merck and Co Inc. compare with other water systems in Montgomery County?
By EPA's size categories, Merck and Co Inc. is a medium system (3,301 to 10,000 people). Montgomery County has 166 active public water systems. Its population served is about 11% above the county average of 7,675 people per system, and accounts for 0.7% of the 1,274,113 people reported by systems filed under the county. Across Pennsylvania, the 7,217 active systems average 1,741 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Merck and Co Inc. is about 20 times that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Pennsylvania has 1,026 active non-transient non-community water systems, 14% of the state's 7,217 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 244 Pennsylvania systems (3.4%) list purchased surface water as their primary source.
Who owns and regulates Merck and Co Inc.?
EPA lists Merck and Co Inc. as privately owned. The PA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 115 of the 166 active systems in Montgomery County (69%) are also privately owned.
Does Merck and Co Inc. have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in March 2025. The violations listed here began between January 2020 and March 2025. By type: 12 monitoring and reporting. The contaminants or rules involved are Surface Water Treatment Rule, Chlorine, Dalapon and Methoxychlor. EPA lists 12 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-03-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2025-03-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dalaponcode 2031 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Methoxychlorcode 2015 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Lindane (gamma-BHC)code 2010 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Diquatcode 2032 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzo(a)pyrenecode 2306 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 2,4-Dcode 2105 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Pentachlorophenolcode 2326 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Polychlorinated biphenyls (PCBs), totalcode 2383 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endrincode 2005 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Toxaphenecode 2020 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Merck and Co Inc.: frequently asked questions
Who runs Merck and Co Inc.?
Merck and Co Inc. (PWSID PA1461065) is a non-transient non-community water system privately owned. It is regulated by the PA state drinking water program.
How many people does Merck and Co Inc. serve?
Merck and Co Inc. reports serving 8,550 people through 1 service connection in Montgomery County, Pennsylvania.
Where does Merck and Co Inc. get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Merck and Co Inc. have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in March 2025. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Merck and Co Inc.'s water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in March 2025. For current results, consult EPA ECHO, or the PA state drinking water program.
Where can I find Merck and Co Inc.'s water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Merck and Co Inc. is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Montgomery County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Aqua Pa Main System | Montgomery | 822,600 | Community | Surface water |
| North Penn Water Authority | Montgomery | 91,941 | Community | Purchased surface water |
| Pa American Norristown | Montgomery | 88,885 | Community | Surface water |
| North Wales Water Authority | Montgomery | 72,496 | Community | Surface water |
| Pottstown Borough Water Auth | Montgomery | 36,000 | Community | Surface water |
| Horsham Water&Sewer Authority | Montgomery | 26,000 | Community | Purchased surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Merck and Co Inc., PWSID PA1461065, Pennsylvania”, https://aquacensus.com/water-systems/pennsylvania/merck-and-co-inc-pa1461065 (data as of October 1, 2026).