Columbia, MD: 18 Violations — 62/100 (2026)
3 ZIP codes · 2 water systems · Updated 2026-06-03
Water monitoring across Columbia paints a mid-range picture within MD — solid compliance in some service zones, documented concerns in others. Most violations on record are concentrated in specific areas, and the overall grade has held in the middle tier without major shifts in recent monitoring cycles.
How Columbia Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Columbia Residents
- Your city's water systems recorded 18 violations in the past 5 years.
- Average lead level: 0.003 mg/L.
- Homes built before 1986: 61% — older plumbing may contain lead solder.
- Estimated remediation: $1,533 per household.
- CDC health risk index: 10.56.
Columbia's Water Providers
Columbia, MD is covered by 2 major water utilities out of 2 federally tracked systems, each managing its own pipes, treatment processes, and EPA filings. What a household gets from the tap depends on which provider's system serves that address.
Overview
We track water quality and home safety data for 3 ZIP codes in Columbia, Maryland (population ~101,074), covering 2 community water systems serving approximately 286,458 people region-wide.
3 of 3 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Columbia: C (62/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Columbia water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0030 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
- Zone 1 (High): 3 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | 8 | 3 |
| Surface Water Treatment Rule | Treatment Technique | 8 | 3 |
| Consumer Confidence Report Rule | Reporting | 8 | 3 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 21044 | C | 6 | 0 | Howard County D.p.w. Distribution |
| 21045 | C | 6 | 0 | Howard County D.p.w. Distribution |
| 21046 | C | 6 | 0 | Howard County D.p.w. Distribution |
All ZIP Codes in Columbia
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Columbia Community Health Snapshot
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
What's in Columbia's Water?
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Columbia Infrastructure Age
With 61% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
When more than half a city's housing predates the 1986 federal ban on lead solder, plumbing-era lead risk becomes a citywide concern rather than an exception. Columbia's median build year of 1981 places it squarely in that category.
Over half of homes in Columbia were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Columbia
While no remediation project is entirely without cost, the relationship between estimated remediation and property values in Columbia is notably favorable — the equity share is small enough that the household financial perspective is one of proportionality rather than pressure, and most homeowners can treat it as routine planning rather than a significant financial event.
Remediation costs in Columbia are relatively low compared to home values. The $1,000–$2,333 estimated range is a small fraction of median property value. Home values are 10% above the Maryland average.
Columbia: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Older stock in Columbia represents 61% of the inventory, and citywide monitoring runs at or above the federal action level — making an in-home read a standard household-level step.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Columbia: Flood History & Water Damage Risk
Within the NFIP's national dataset, Columbia falls in moderate-exposure territory — 60 documented incidents spanning multiple decades, with 100% of local ZIP codes sitting inside FEMA flood boundaries. That combination warrants inclusion in any thorough local water quality review.
Columbia has a moderate flood history with 60 FEMA claims averaging $2,296 per payout. 100% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,533</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Columbia
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Stage 1 DBP Rule can reduce the most common contaminant found in Columbia's water.
- Check your home's plumbing. With 61% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Columbia, MD