Public water system · IA6000800
ActiveLyon-Sioux Rws-Rock Rapids
At a glance
Lyon-Sioux Rws-Rock Rapids (PWSID IA6000800) is an active community water system in Lyon County, Iowa. It reports serving 1,187 people through 475 service connections. Its primary water source is purchased groundwater, and EPA lists it as privately owned. EPA's records list one violation for this system; it is health-based, and the most recent began in December 2007.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,187
Service connections
475
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Lyon-Sioux Rws-Rock Rapids compare with other water systems in Lyon County?
By EPA's size categories, Lyon-Sioux Rws-Rock Rapids is a small system (501 to 3,300 people). Lyon County has 12 active public water systems, and Lyon-Sioux Rws-Rock Rapids is the 4th-largest of them by population served. Its population served is about 17% above the county average of 1,016 people per system, and accounts for 9.7% of the 12,196 people reported by systems filed under the county. Across Iowa, the 1,828 active systems average 1,718 people each. Nationally, the average active community water system reports serving 6,703 people, so Lyon-Sioux Rws-Rock Rapids is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Iowa has 1,084 active community water systems, 59% of the state's 1,828 active systems. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. 156 Iowa systems (8.5%) list purchased groundwater as their primary source.
Who owns and regulates Lyon-Sioux Rws-Rock Rapids?
EPA lists Lyon-Sioux Rws-Rock Rapids as privately owned. The IA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 4 of the 12 active systems in Lyon County (33%) are also privately owned.
Does Lyon-Sioux Rws-Rock Rapids have drinking water violations?
EPA's records list one violation for this system; it is health-based, and the most recent began in December 2007. By type: 1 contaminant level above the legal limit. The contaminant or rule involved is Total coliform bacteria (TCR). EPA lists 1 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 |
|---|---|---|---|---|
| 2007-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
The one violation in EPA's records.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.
Lyon-Sioux Rws-Rock Rapids: frequently asked questions
Who runs Lyon-Sioux Rws-Rock Rapids?
Lyon-Sioux Rws-Rock Rapids (PWSID IA6000800) is a community water system privately owned. It is regulated by the IA state drinking water program.
How many people does Lyon-Sioux Rws-Rock Rapids serve?
Lyon-Sioux Rws-Rock Rapids reports serving 1,187 people through 475 service connections in Lyon County, Iowa.
Where does Lyon-Sioux Rws-Rock Rapids get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Lyon-Sioux Rws-Rock Rapids have any drinking water violations?
EPA's records list one violation for this system; it is health-based, and the most recent began in December 2007. 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 Lyon-Sioux Rws-Rock Rapids' 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 one violation for this system; it is health-based, and the most recent began in December 2007. For current results, consult the system's annual water quality report, EPA ECHO, or the IA state drinking water program.
Where can I find Lyon-Sioux Rws-Rock Rapids' water quality report?
As a community water system, Lyon-Sioux Rws-Rock Rapids must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Lyon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Rock Rapids Municipal Water Works | Lyon | 2,611 | Community | Groundwater |
| Lyon-Sioux Rws-Doon | Lyon | 1,765 | Community | Groundwater |
| Lyon-Sioux Rws-Big Sioux | Lyon | 1,530 | Community | Groundwater |
| George Water Supply | Lyon | 1,082 | Community | Groundwater |
| Inwood Water Supply | Lyon | 928 | Community | Purchased groundwater |
| Larchwood Water Supply | Lyon | 926 | Community | Purchased 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, “Lyon-Sioux Rws-Rock Rapids, PWSID IA6000800, Iowa”, https://aquacensus.com/water-systems/iowa/lyon-sioux-rws-rock-rapids-ia6000800 (data as of October 1, 2026).