PlainWater
Counties → Iowa

Johnson County, Iowa

Water Systems
125
Population Served
167,742
Total Violations
10,912
3,415 health-based
PFAS Detected
5
of 5 tested

Violation Analysis

96.0%
Systems with Violations
87.3
Avg Violations per System
31.3%
Health-Based Violations

Water Source Types

GW
48 systems (38%)
SW
2 systems (2%)

PFAS Contamination

5
Systems Tested
5
PFAS Detected
100.0%
Detection Rate

PFAS (per- and polyfluoroalkyl substances) are persistent chemicals found in drinking water. The EPA has set enforceable limits for several PFAS compounds under UCMR5 monitoring.

Compliance Snapshot

Johnson Iowa water systems by violation status, EPA SDWIS records.

No violations on record (1) One or more violations (49)

Violation history is cumulative, many flagged systems have already returned to compliance. Detail pages show per-system context.

Water Systems

System Name Population Violations PFAS
Iowa City Water Department 68,753 130 Clean
University Water System 26,684 89 Clean
Coralville Muni Water System 22,318 198 Clean
North Liberty Water Supply 20,491 46 Clean
Tiffin Water Supply 4,512 40 -
Solon Water Dept 3,018 30 -
Lone Tree Muni Water System 1,357 46 -
Lake Ridge, Incorporated 1,300 106 -
F W Kent Park 1,169 27 -
Modern Manor, Inc 915 72 -
Hills Water Supply 863 5 -
Coralville Lake-West Overlook 861 82 -
Western Hills (Mobile) Estates 760 177 -
Oxford Water Supply 722 127 -
Iowa City Regency Mobile Home Community 700 229 -
Coralville Lake-Sugar Bottom 689 27 -
Cedar Ridge Vineyards 470 87 -
Oakdale Hospital Water System 450 8 -
Shueyville United Methodist Church 410 106 -
Gateway Development 400 99 -
River Heights Property Owners Assoc. 390 74 -
Fox Ridge Farm 374 8 -
Sunrise Village Mobile Home Pk 340 75 -
Coralville Lake Terrace 340 362 -
Parkview Mobile Home Court 300 32 -
Lake Crest Manor HOA #3 300 65 -
Iowa City MHP LLC 280 87 Clean
Coralville Lake-Ad Bldg 275 88 -
Kalona Creamery, LLC 262 33 -
380Bp Swisher 258 58 -
Sutliff Holdings LLC 250 4 -
High Point City Church 233 8 -
Johnson County Ag Association 218 137 -
Cottage Reserve Corporation 198 70 -
Sharon Bethel Church/School 195 30 -
North Twin View Heights 180 89 -
Iadu Clear MHP LLC 173 50 -
Coralville Lake Manor 170 82 -
Spring Valley Homeowners Assn. 163 73 -
Royal Oaks Subdivision 163 41 -
Plum Creek Boutique Dance Mor 160 0 -
Prairie View Estates Assoc Johnson Cnty 155 544 -
Twin View Heights 155 113 -
Coralville Lake-Sandy Beach 147 38 -
Forestgate Subdivision 140 10 -
Lake Vista Subdivision 134 34 -
Pleasant Valley Golf Course 130 33 -
Lakeview Knolls Homeowners Assn. 122 153 -
Westcott Heights HOA Part Three 120 14 -
Lake Woods HOA 114 126 -

Other Counties in Iowa

Polk County
38 systems · 552,627 served · 1,563 violations
Linn County
83 systems · 224,711 served · 8,540 violations
Scott County
77 systems · 178,285 served · 5,956 violations
Black Hawk County
19 systems · 161,225 served · 824 violations
Story County
21 systems · 121,108 served · 1,299 violations
Woodbury County
32 systems · 99,461 served · 1,715 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in Johnson County? ▼
Johnson County has 10,912 total drinking water violations across 125 water systems, of which 3,415 are health-based violations. 96.0% of systems have at least one violation.
How many people get water from Johnson County systems? ▼
Water systems in Johnson County serve approximately 167,742 people through 125 public water systems.
Has PFAS been detected in Johnson County water? ▼
Of 5 water systems tested for PFAS in Johnson County, 5 had PFAS detected (100.0% detection rate).
What types of water sources supply Johnson County? ▼
Water systems in Johnson County use GW (48 systems), SW (2 systems) as their primary water sources.
Are health-based violations serious? ▼
Health-based violations indicate that drinking water exceeded Maximum Contaminant Levels (MCLs) set by the EPA or failed treatment technique requirements. 31.3% of Johnson County's violations are health-based. Not all violations indicate immediate health risk, but they require corrective action.
Data Sources & Methodology

Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). PFAS testing data from the UCMR5 monitoring program. SDWIS tracks all public water systems regulated under the Safe Drinking Water Act.

Violations are categorized as health-based (Maximum Contaminant Level exceedances, treatment technique failures) or monitoring/reporting violations. Not all violations indicate an immediate health risk.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.