Public water system · SD4600650
ActiveCuster-Mount Rushmore Koa-Rear/Cg
At a glance
Custer-Mount Rushmore Koa-Rear/Cg (PWSID SD4600650) is an active transient non-community water system in Custer County, South Dakota. It reports serving 146 people through 67 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in June 2016.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
146
Service connections
67
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Custer-Mount Rushmore Koa-Rear/Cg compare with other water systems in Custer County?
By EPA's size categories, Custer-Mount Rushmore Koa-Rear/Cg is a very small system (500 people or fewer). Custer County has 49 active public water systems. Its population served is about half of the county average of 274 people per system, and accounts for 1.1% of the 13,414 people reported by systems filed under the county. Across South Dakota, the 699 active systems average 1,387 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Custer-Mount Rushmore Koa-Rear/Cg is roughly in line with 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. South Dakota has 173 active transient non-community water systems, 25% of the state's 699 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 431 South Dakota systems (62%) list groundwater as their primary source.
Who owns and regulates Custer-Mount Rushmore Koa-Rear/Cg?
EPA lists Custer-Mount Rushmore Koa-Rear/Cg as privately owned. The SD state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 27 of the 49 active systems in Custer County (55%) are also privately owned.
Does Custer-Mount Rushmore Koa-Rear/Cg have drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in June 2016. The violations listed here began between June 2008 and June 2016. By type: 5 public notice, recordkeeping or other, 4 contaminant level above the legal limit and 3 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). 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 |
|---|---|---|---|---|
| 2016-06-01 | Public notice, recordkeeping or otherSample Siting Plan Errors (RTCR) · code 5A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2013-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2011-06-05 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2011-06-05 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2011-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2010-11-08 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2010-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-07-08 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2008-07-08 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2008-07-01 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2008-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | 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.
Custer-Mount Rushmore Koa-Rear/Cg: frequently asked questions
Who runs Custer-Mount Rushmore Koa-Rear/Cg?
Custer-Mount Rushmore Koa-Rear/Cg (PWSID SD4600650) is a transient non-community water system privately owned. It is regulated by the SD state drinking water program.
How many people does Custer-Mount Rushmore Koa-Rear/Cg serve?
Custer-Mount Rushmore Koa-Rear/Cg reports serving 146 people through 67 service connections in Custer County, South Dakota.
Where does Custer-Mount Rushmore Koa-Rear/Cg get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Custer-Mount Rushmore Koa-Rear/Cg have any drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in June 2016. 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 Custer-Mount Rushmore Koa-Rear/Cg'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, 4 are health-based, and the most recent began in June 2016. For current results, consult EPA ECHO, or the SD state drinking water program.
Where can I find Custer-Mount Rushmore Koa-Rear/Cg's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Custer-Mount Rushmore Koa-Rear/Cg 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 Custer County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Laughing Water Restaurant at Crazy H | Custer | 2,055 | Non-transient non-community | Groundwater |
| Custer | Custer | 1,919 | Community | Groundwater |
| Nps-Wind Cave National Park | Custer | 1,404 | Non-transient non-community | Groundwater |
| Southern Black Hills Water | Custer + 1 more | 947 | Community | Groundwater |
| Csp-Sylvan Lake | Custer | 799 | Transient non-community | Groundwater |
| Csp-Game Lodge | Custer | 541 | Transient non-community | Groundwater |
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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, “Custer-Mount Rushmore Koa-Rear/Cg, PWSID SD4600650, South Dakota”, https://aquacensus.com/water-systems/south-dakota/custer-mount-rushmore-koa-rear-cg-sd4600650 (data as of October 1, 2026).