LYON-SIOUX RWS-BIG SIOUX
Iowa — Community Water System — PWSID: IA6000755
System Information
| PWSID | IA6000755 |
| System Name | LYON-SIOUX RWS-BIG SIOUX |
| System Type | Community Water System |
| Water Source | Ground Water |
| Activity Status | Active |
| Owner Type | Private |
| EPA Region | 07 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Feb 27, 1979 |
| Last Reported | Mar 17, 2026 |
Location & Contact
| State | Iowa |
| City | ROCK RAPIDS |
| ZIP Code | 51246 |
| Address | ATTN DAVE HARMSEN |
| Organization | LYON-SIOUX RURAL WATER SYSTEM |
| Phone | 712-472-3755 |
Population & Service
| Population Served | 1,530 |
| Service Connections | 612 |
Drinking Water Violations (71)
This water system has 71 violations recorded in the EPA SDWIS database.
| Begin Date | End Date | Contaminant | Category | Health-Based | Major | Measured | Federal MCL | State MCL | Status | Return to Compliance | Rule |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Oct 1, 2019 | Sep 30, 2020 | MR | No | Yes | — | 1 mg/L | — | Resolved | Sep 30, 2020 | — | |
| Oct 1, 2019 | Sep 30, 2020 | MR | No | Yes | — | 1 mg/L | — | Resolved | Sep 30, 2020 | — | |
| Oct 1, 2019 | Sep 30, 2020 | MR | No | Yes | — | 1 mg/L | — | Resolved | Sep 30, 2020 | — | |
| Oct 1, 2019 | Sep 30, 2020 | MR | No | Yes | — | 1 mg/L | — | Resolved | Sep 30, 2020 | — | |
| Jul 1, 2012 | Jun 30, 2021 | MR | No | Yes | — | 5 pCi/L | — | Resolved | Jun 30, 2021 | — | |
| Jul 1, 2012 | Jun 30, 2021 | MR | No | Yes | — | 5 pCi/L | — | Resolved | Jun 30, 2021 | — | |
| Jul 1, 2012 | Jun 30, 2021 | MR | No | Yes | — | 5 pCi/L | — | Resolved | Jun 30, 2021 | — | |
| Jul 1, 2012 | Jun 30, 2021 | MR | No | Yes | — | 5 pCi/L | — | Resolved | Jun 30, 2021 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MR | No | Yes | — | 10 mg/L | — | Resolved | Sep 30, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MR | No | Yes | — | 10 mg/L | — | Resolved | Sep 30, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MR | No | Yes | — | 10 mg/L | — | Resolved | Sep 30, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MR | No | Yes | — | 10 mg/L | — | Resolved | Sep 30, 2010 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.05 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 4.0 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.05 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 4.0 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.005 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.006 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.006 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.006 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.006 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.010 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.010 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.1 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.010 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.010 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 2 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 2 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.005 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.005 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.1 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.1 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 4.0 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 4.0 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.05 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.05 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.002 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 2 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 2 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.005 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jan 1, 2005 | Dec 31, 2013 | MR | No | Yes | — | 0.1 mg/L | — | Resolved | Dec 31, 2013 | — | |
| Jun 1, 2004 | — | MR | No | No | — | TT | — | Resolved | Aug 14, 2007 | — | |
| Jun 1, 2004 | — | MR | No | No | — | TT | — | Resolved | Aug 14, 2007 | — |
About This Water System
Public water system data comes from the EPA Safe Drinking Water Information System (SDWIS). Systems with violations must notify customers. Contact your water utility for the latest annual water quality report.