WaterVerge

Is Marshalltown, IA Tap Water Safe to Drink?

Graded A-, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

29K residents served 3 water systems PWSID: IA6469042
Overall Score
88.4 / 100
Violations
3 active
Last Updated
May 2026
Source
Groundwater
#263 of 436 in Iowa Top 22% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
88.4/100
waterverge.com
A- 88.4/100

Marshalltown, IA — Water Quality Report

Marshalltown's drinking water received a grade of A- (88.4 out of 100), indicating good water quality. The city's 3 water systems serve approximately 28,501 residents using groundwater.

Lead levels were measured at 2.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 45 violations on record, including 4 health-based violations. 3 remain unresolved.

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

What to know about Marshalltown's water

Marshalltown ranks #263 out of 436 cities in Iowa for water quality, placing it below average in the state.

Marshalltown relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

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.

Hexavalent chromium (chromium-6) was detected at 0.33 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

Quality Breakdown

Water quality score

See methodology →
88.4 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
40.6/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 2.0 ppb (90th percentile).
Contaminants
14.8/20
B
1 PFAS compound detected.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Marshalltown, IA water safe to drink?

Concerns Identified

Marshalltown's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (88.4/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 28,501 residents using groundwater (wells).

3
Active Violations
2.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
10 events
Disaster History

Recent water quality updates for Marshalltown

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 Marshalltown's water quality assessment. Grade: A- (88.4/100).

Violation
1 drinking water violation recorded

Contaminants: Nitrate.

Violation
1 drinking water violation recorded

Contaminants: Revised Total Coliform Rule.

Disaster
SEVERE STORMS AND FLOODING

Federal disaster declaration (FEMA DR-4421). Flood event — may have impacted local water infrastructure.

Violation
11 drinking water violations recorded

Contaminants: Beryllium, Total, CYANIDE, Cadmium.

Key contaminant findings

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

Lead Within Limits
Detected: 2.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 20.0000 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

Marshalltown's water system has 45 total violations on record, including 4 health-based violations. 3 remain unresolved. 2 violations were issued in the last 5 years.

MRMONMCL
Most recent violations:
Jul 2024 Nitrate Resolved
Sep 2021 Revised Total Coliform Rule Resolved
Oct 2015 Beryllium, Total Resolved
Oct 2015 CYANIDE Resolved
Oct 2015 Cadmium Resolved

Flood & environmental risk

Marshall County has experienced 10 federally declared disasters since 1965. 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 Iowa River At Marshalltown, Timber Creek Near Marshalltown.

SEVERE STORMS AND FLOODING
Flood FEMA DR-4421
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3239
SEVERE STORMS, TORNADOES AND FLOODING
Flood FEMA DR-1230

Where does Marshalltown's water come from?

Marshalltown's drinking water comes from groundwater (wells), supplied by 3 water systems serving approximately 28,501 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Iowa River At Marshalltown (river), Timber Creek Near Marshalltown (river).

What Marshalltown residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Marshalltown's water.

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

Marshalltown'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
2.0 ppb
EPA Action Level: 15 ppb · 13% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
20.0000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
0.6 µg/L
EPA MCL: 60 µg/L · 1% of limit
Within LimitUCMR 4 DataHAA6Br: 0.0 µg/LHAA9: 0.6 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.33 µg/L
CA MCL (no federal MCL): 10 µg/L · 3% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
170.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 11% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Detected
0.11 µg/L
EPA Health Advisory: 0.35 µg/L · 30% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Detected
4.0 µg/L
EPA Secondary MCL: 50 µg/L · 8% of limit
DetectedUCMR 4 Data
Chlorate
Disinfection Byproduct
Elevated
187.0 µg/L
EPA Lifetime HA: 210 µg/L · 89% of limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
1.60 µg/L
EPA Lifetime HA: 40 µg/L · 4% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
20.0 µg/L
State screening level: 60 µg/L · 33% 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

45
Total violations
4
Health-based
3
Active / unresolved
Jul 2024
Most recent violation
Compliance Record

Violations & advisories

45 Total
3 Active
4 Health-based
42 Resolved
Violations by category
Total Coliform Rule
18
Inorganic Chemicals
11
Nitrate Rule
6
Radionuclides and Revised Rad Rule
3
Revised Total Coliform Rule
1
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Jul 2024 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Sep 2021 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Sep 2021
Oct 2015 Resolved
Beryllium, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
CYANIDE
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Cadmium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Fluoride
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Selenium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Thallium, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Barium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Antimony, Total
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Mercury
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Arsenic
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Oct 2015 Resolved
Chromium
Monitoring & Reporting
Monitoring & Reporting Resolved Sep 2024
Nov 2014 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Nov 2014
Apr 2008 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Apr 2008
Apr 2008 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Apr 2008
Mar 1997 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 1997
Showing 20 of 45 violations
Industrial pollution

Top industrial polluters within 10 miles of Marshalltown

Industrial polluters nearby

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

Total reported releases to surface water: 21 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
FISHER CONTROLS INTERNATIONAL LLC
Fabricated Metals · EMERSON ELECTRIC CO
MARSHALLTOWN, IA50158
Manganese210.8 mi
DIAMOND VOGEL INC.
Chemicals · DIAMOND VOGEL INC
MARSHALLTOWN, IA50158
0.4 mi
LENNOX INDUSTRIES INC
Machinery · LENNOX INTERNATIONAL INC
MARSHALLTOWN, IA50158
1.1 mi
SWIFT PORK
Food · JBS USA FOOD CO
MARSHALLTOWN, IA50158
1.5 mi
FORTERRA CONCRETE PRODUCTS - MARSHALLTOWN
Nonmetallic Mineral Product · QUIKRETE HOLDINGS
MARSHALLTOWN, IA50158
1.5 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Environmental Risk

Flood & disaster history

10
Declared disasters
Mar 2019
Most recent
Flood
Most common type

Marshall County has experienced 10 federally declared disasters since 1965. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Mar 2019
SEVERE STORMS AND FLOODING
Flood FEMA #4421
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
Jul 1991
SEVERE STORMS & FLOODING
Flood FEMA #911
May 1990
SEVERE STORMS & FLOODING
Flood FEMA #868

Recommended water filters

Based on contaminants detected in Marshalltown'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) 2.0 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 20.000 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 0.0 ppb from 1992 (0.0 ppb) to 2025 (0.0 ppb).
Contaminant Rankings

See how Marshalltown compares by contaminant

Explore where Marshalltown ranks among all Iowa cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
28,501
Water Systems
3
Source breakdown
Groundwater
2
Purchased Groundwater
1
Water Source

Where Marshalltown's water comes from

Groundwater

Marshalltown's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by local government ownership and serves approximately 28,501 people through 3 water systems.

Local Hydrology

Water bodies near Marshalltown

Marshalltown is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Iowa River At Marshalltown
river
Timber Creek Near Marshalltown
river
Infrastructure

Water systems serving Marshalltown

System Name PWSID Population Source
MARSHALLTOWN WATER WORKS IA6469042 27,591 GW
SUNSET VILLAGE IA6469601 528 GWP
MARSHALLTOWN ESTATES IA6400628 382 GW
Regional Comparison

How Marshalltown compares

Full Iowa rankings →

Marshalltown's score of 88.4/100 is above the average of 72/100 among major Iowa cities. It outscores 10 of 10 nearby cities.

Marshalltown (this city)
88.4
Ames
81.5
Iowa avg
72
City Profile

About Marshalltown, IA

Wikipedia →

Marshalltown is a city in Marshall County, Iowa, United States and the county seat of the county. The population was 27,591 at the 2020 census, and was estimated at 27,886 in 2024, making it the 17th-most populous city in Iowa. Marshalltown is home to the Iowa Veterans Home and Marshalltown Community College.

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Frequently asked questions

Is Marshalltown, IA tap water safe to drink?

Marshalltown's water quality earned a grade of A- (88.4/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #263 out of 436 cities tested in Iowa.

What contaminants are in Marshalltown's water?

Lead was measured at 2.0 ppb (90th percentile). 1 PFAS compound was detected. 45 violations are on record.

How is Marshalltown'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 Marshalltown?

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

Where does Marshalltown's water come from?

Marshalltown's water is sourced from Groundwater. The city has 3 water systems serving approximately 28,501 residents.

What health violations has Marshalltown's water system had?

Marshalltown has 4 health-based violations on record. The most recent violation was recorded in July 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.

Is Marshalltown's groundwater at risk of contamination?

Marshalltown uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 45 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Marshalltown's water compare to other cities?

Marshalltown ranks #263 out of 436 cities in Iowa (better than 40% of state cities) and #3451 out of 15744 cities nationally (78th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.