Marshall County Water Quality
Marshall County, Iowa
Water Grade
A
Water Score
86.0
Violations
0
State Rank
#45
of 99 (1 = best)
EPA SDWIS Compliance
Drinking Water Quality
Water Quality Grade
A
Based on EPA compliance history and violation data
Water Score
86/100
Higher = better quality
Health Violations
0
Health-based violations
Violation Rate
0.0%
Systems with violations
Water Advisory: Marshall County
Water Verdict
Marshall County receives an excellent water quality assessment with a grade of A and a score of 86.0 out of 100. The water supply meets or exceeds federal safety standards, and residents can generally drink tap water with confidence.
Violation Context
Marshall County has recorded zero health-based violations, indicating that the water system has met all federal safety standards during the reporting period. The violation rate is zero per 1,000 residents, which is the best possible outcome.
Consumer Guidance
Tap water in Marshall County is generally safe to drink based on available data. Residents should still review their utility's annual Consumer Confidence Report for transparency on detected contaminants. For long-term peace of mind, request your utility's latest Consumer Confidence Report and consider independent water testing if you have specific health concerns.
Regional Context
Marshall County has better water quality than the average county in Iowa. Its water score is 14.3 points higher than the state average, indicating stronger water system performance relative to neighboring counties.
Past 5 years
Water Quality Monitoring
Monitoring Sites
5
Active in the past 5 years
Measurements Recorded
2.0K
2,008 total readings
Most Measured
- Physical
- Nutrient
- Inorganics, Minor, Metals
Categories measured most frequently
Data from the EPA Water Quality Portal (WQP), aggregating monitoring records from federal, state, and tribal sources. Each measurement represents a single sample analyzed for a specific characteristic (e.g., E. coli, pH, dissolved oxygen, nitrogen).
Live USGS Streamgage
River & Stream Conditions
Current Discharge
739cfs
May 14, 7:00 PM UTC
vs Long-Term Average
76%
Below typicalPrimary Streamgage
Iowa River at Marshalltown, IA
- USGS site
- 05451500
- Drainage area
- 1,532 sq mi
- Long-term mean
- 976 cfs
One representative streamgage (the one with the largest drainage area in the county). Many counties have multiple gauges — this view summarizes the primary one. The long-term mean is the full-record annual average; "% of typical" compares the latest reading against that average.
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Frequently Asked Questions
What is the water quality in Marshall County, Iowa?
Are there any water violations in Marshall County?
How much water-quality monitoring happens in Marshall County?
What's happening with rivers in Marshall County right now?
How does Marshall County water compare to the Iowa average?
Is tap water safe to drink in Marshall County?
Does Marshall County have clean drinking water?
How does Marshall County rank for water quality in Iowa?
Counties with Similar Water Quality
Data Sources
Drinking-water compliance data from the EPA Safe Drinking Water Information System (SDWIS) via the ECHO enforcement database. Scores reflect compliance history and health-based violation counts.
Water-quality monitoring counts from the EPA Water Quality Portal (WQP) — federated USGS, EPA, and state agency sampling records over a rolling 5-year window.
Live streamflow from the USGS National Water Information System (NWIS) — continuous discharge measurements from the largest-drainage gauge in each county, compared against the full-record long-term annual mean.
Disclaimer: This data is informational only. It is not health, legal, or professional advice. For concerns about your specific water supply, contact your local water utility.