WaterVerge

Is Norwalk, IA Tap Water Safe to Drink?

Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

15K residents served 2 water systems PWSID: IA9164078
Overall Score
93.2 / 100
Violations
2 active
Last Updated
May 2026
Source
Purchased surface water
#59 of 436 in Iowa Top 6% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
AGRADE
Water Quality Grade
93.2/100
waterverge.com
A 93.2/100

Norwalk, IA — Water Quality Report

Norwalk's drinking water received a grade of A (93.2 out of 100), indicating excellent water quality. The city's 2 water systems serve approximately 14,550 residents using purchased surface water.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 10 violations on record, including 1 health-based violation. 2 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Norwalk's water

Norwalk ranks #59 out of 436 cities in Iowa for water quality, placing it above average in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Quality Breakdown

Water quality score

See methodology →
93.2 out of 100 Grade A
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
43.9/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
17.2/20
B
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Purchased surface water.
Water Safety

Is Norwalk, IA water safe to drink?

Use Caution

Norwalk's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (93.2/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 2 water systems serve approximately 14,550 residents using surface water (rivers, lakes, or reservoirs).

2
Active Violations
0.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
7 events
Disaster History

Recent water quality updates for Norwalk

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Norwalk's water quality assessment. Grade: A (93.2/100).

Disaster
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING

Federal disaster declaration (FEMA DR-4119). Flood event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Coliform (TCR).

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3239). Hurricane event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

Contaminants: Coliform (TCR).

Key contaminant findings

Based on the most recent EPA sampling data for Norwalk's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 47.6000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Norwalk's water system has 10 total violations on record, including 1 health-based violation. 2 remain unresolved.

MRMCL
Most recent violations:
Aug 2011 Coliform (TCR) Resolved
Oct 2003 Coliform (TCR) Resolved
Jul 2003 Coliform (TCR) Resolved
Aug 2001 Coliform (TCR) Resolved
Dec 1999 Coliform (TCR) Resolved

Flood & environmental risk

Warren County has experienced 7 federally declared disasters since 1973. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Des Moines River At 2Nd Avenue At Des Moines, Raccoon River Near West Des Moines, Raccoon River At 63Rd Street At Des Moines, Walnut Creek At Des Moines, Raccoon River At Fleur Drive At Des Moines.

SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA DR-4119
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3239
SEVERE STORMS, TORNADOES AND FLOODING
Flood FEMA DR-1230

Where does Norwalk's water come from?

Norwalk's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 2 water systems serving approximately 14,550 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Des Moines River At 2Nd Avenue At Des Moines (river), Raccoon River Near West Des Moines (river), Raccoon River At 63Rd Street At Des Moines (river), Walnut Creek At Des Moines (river), Raccoon River At Fleur Drive At Des Moines (river).

What Norwalk residents can do

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Norwalk's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
47.6000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
Lithium
Inorganic
Detected
47.6 µg/L
State screening level: 60 µg/L · 79% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

10
Total violations
1
Health-based
2
Active / unresolved
Aug 2011
Most recent violation
Compliance Record

Violations & advisories

10 Total
2 Active
1 Health-based
8 Resolved
Violations by category
Total Coliform Rule
7
Lead and Copper Rule
1
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Aug 2011 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2011
Oct 2003 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 2003
Jul 2003 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jul 2003
Aug 2001 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Aug 2001
Dec 1999 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 1999
Jul 1993 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 1993
Jul 1992 Resolved
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2002
Oct 1990 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Oct 1990
Industrial pollution

Top industrial polluters within 10 miles of Norwalk

Industrial polluters nearby

Reported releases to surface water by facilities near Norwalk, ranked by pounds discharged annually.

Total reported releases to surface water: 24 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
TITAN TIRE CORP
Plastics and Rubber · TITAN INTERNATIONAL INC
DES MOINES, IA50317
Zinc compounds249.6 mi
NORTHFIELD-RHINO
Nonmetallic Mineral Product · CRH AMERICAS INC
WEST DES MOINES, IA50265
Lead05.7 mi
MICHAEL FOODS NORWALK
Food · MICHAEL FOODS INC
NORWALK, IA50211
5.5 mi
CENTRAL IOWA READY MIX WEST DES MOINES
Nonmetallic Mineral Product · RASMUSSEN GROUP
WEST DES MOINES, IA50265
5.9 mi
FORTERRA PIPE & PRECAST - WEST DES MOINES
Nonmetallic Mineral Product · QUIKRETE HOLDINGS
WEST DES MOINES, IA50265
5.8 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Norwalk

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

7
Declared disasters
May 2013
Most recent
Flood
Most common type

Warren County has experienced 7 federally declared disasters since 1973. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

May 2013
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA #4119
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3239
Jul 1998
SEVERE STORMS, TORNADOES AND FLOODING
Flood FEMA #1230
Jul 1993
SEVERE STORMS & FLOODING
Flood FEMA #996
May 1990
SEVERE STORMS & FLOODING
Flood FEMA #868
Jun 1974
SEVERE STORMS & FLOODING
Flood FEMA #443

Recommended water filters

Based on contaminants detected in Norwalk's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 47.600 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 9.0 ppb from 1992 (9.0 ppb) to 2025 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Purchased Surface Water
Operator
Local Government
Population Served
14,550
Water Systems
2
Water Source

Where Norwalk's water comes from

Purchased Surface Water

Norwalk's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by local government ownership and serves approximately 14,550 people through 2 water systems.

Local Hydrology

Water bodies near Norwalk

Norwalk is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.

Des Moines River At 2Nd Avenue At Des Moines
river
Raccoon River Near West Des Moines
river
Raccoon River At 63Rd Street At Des Moines
river
Walnut Creek At Des Moines
river
Raccoon River At Fleur Drive At Des Moines
river
Infrastructure

Water systems serving Norwalk

System Name PWSID Population Source
NORWALK WATER SUPPLY IA9164078 14,334 SWP
WILSHIRE HILLS MHC IA9164601 216 SWP
Regional Comparison

How Norwalk compares

Full Iowa rankings →

Norwalk's score of 93.2/100 is above the average of 72/100 among major Iowa cities. It outscores 10 of 10 nearby cities.

Norwalk (this city)
93.2
Ames
81.5
Iowa avg
72
City Profile

About Norwalk, IA

Wikipedia →

Norwalk is a city in Warren County, with some small portions extending into Polk County, in the U.S. state of Iowa. The population was 12,799 at the time of the 2020 census. The city is part of the Des Moines metropolitan area and is located just south of the Des Moines International Airport.

Economic Profile
$94,176
Median Income
$256,932
Median Home Value
$956/mo
Median Rent
3.1%
Unemployment
Community
36.6
Median Age
436
People / sq mi
39.1%
College Educated
84%
Homeownership
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Frequently asked questions

Is Norwalk, IA tap water safe to drink?

Norwalk's water quality earned a grade of A (93.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #59 out of 436 cities tested in Iowa.

What contaminants are in Norwalk's water?

Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 10 violations are on record.

How is Norwalk's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Norwalk?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Norwalk's water come from?

Norwalk's water is sourced from Purchased surface water. The city has 2 water systems serving approximately 14,550 residents.

What health violations has Norwalk's water system had?

Norwalk has 1 health-based violation on record. The most recent violation was recorded in August 2011. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.

How does Norwalk's water compare to other cities?

Norwalk ranks #59 out of 436 cities in Iowa (better than 86% of state cities) and #913 out of 15744 cities nationally (94th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.