Public water system · NY4317684
ActiveLake Welch + Sebago Beach W.S.
At a glance
Lake Welch + Sebago Beach W.S. (PWSID NY4317684) is an active transient non-community water system in Rockland County, New York. It reports serving 15,000 people through 15 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a state government. EPA's records list 8 violations for this system; 3 are health-based, and the most recent began in August 2017.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
15,000
Service connections
15
Primary source
SWP
Purchased surface water
System type
TNCWS
Transient non-community water system
System record
How does Lake Welch + Sebago Beach W.S. compare with other water systems in Rockland County?
By EPA's size categories, Lake Welch + Sebago Beach W.S. is a large system (10,001 to 100,000 people). Rockland County has 50 active public water systems, and Lake Welch + Sebago Beach W.S. is the 2nd-largest of them by population served. Its population served is about 130% above the county average of 6,530 people per system, and accounts for 4.6% of the 326,504 people reported by systems filed under the county. Across New York, the 8,167 active systems average 2,374 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Lake Welch + Sebago Beach W.S. is about 104 times that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. New York has 5,182 active transient non-community water systems, 63% of the state's 8,167 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 399 New York systems (4.9%) list purchased surface water as their primary source.
Who owns and regulates Lake Welch + Sebago Beach W.S.?
EPA lists Lake Welch + Sebago Beach W.S. as owned by a state government. The NY state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 3 of the 50 active systems in Rockland County (6%) are also owned by a state government.
Does Lake Welch + Sebago Beach W.S. have drinking water violations?
EPA's records list 8 violations for this system; 3 are health-based, and the most recent began in August 2017. The violations listed here began between April 2001 and August 2017. By type: 4 monitoring and reporting, 3 required treatment not met and 1 monitoring. The contaminant or rule involved most often is Surface Water Treatment Rule (4 of them). EPA lists 4 as resolved and 4 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2017-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2015-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-05-01 | Required treatment not metMonthly Turbidity Exceed (Enhanced SWTR) · code 44 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
| 2003-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2002-06-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 2002-05-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Archived |
| 2001-05-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Archived |
| 2001-04-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Archived |
All 8 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.
Lake Welch + Sebago Beach W.S.: frequently asked questions
Who runs Lake Welch + Sebago Beach W.S.?
Lake Welch + Sebago Beach W.S. (PWSID NY4317684) is a transient non-community water system owned by a state government. It is regulated by the NY state drinking water program.
How many people does Lake Welch + Sebago Beach W.S. serve?
Lake Welch + Sebago Beach W.S. reports serving 15,000 people through 15 service connections in Rockland County, New York.
Where does Lake Welch + Sebago Beach W.S. 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 Lake Welch + Sebago Beach W.S. have any drinking water violations?
EPA's records list 8 violations for this system; 3 are health-based, and the most recent began in August 2017. 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 Lake Welch + Sebago Beach W.S.'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. EPA's records list 8 violations for this system; 3 are health-based, and the most recent began in August 2017. For current results, consult EPA ECHO, or the NY state drinking water program.
Where can I find Lake Welch + Sebago Beach W.S.'s water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Lake Welch + Sebago Beach W.S. is a 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 Rockland County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Veolia Water New York | Rockland | 270,000 | Community | Surface water |
| Nyack Village Water Supply | Rockland | 14,700 | Community | Surface water |
| Suffern Village | Rockland | 12,000 | Community | Groundwater |
| Yeshiva Washington Ave | Rockland | 1,000 | Non-transient non-community | Groundwater |
| West Maple Farm | Rockland | 1,000 | Transient non-community | Groundwater |
| Deer Mountain Day Camp | Rockland | 1,000 | Transient non-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, “Lake Welch + Sebago Beach W.S., PWSID NY4317684, New York”, https://aquacensus.com/water-systems/new-york/lake-welch-sebago-beach-w-s-ny4317684 (data as of October 1, 2026).