Tap Water Quality Report

Tap water quality in COLUMBIA, Maryland

Served by HOWARD COUNTY D.P.W. DISTRIBUTION. 286,158 residents.

Average score 78/100
Utilities 1
Population 286,158
Quick answer

Tap water in COLUMBIA, Maryland receives a grade of C (78/100) from TapWaterSafety.org. It's served by HOWARD COUNTY D.P.W. DISTRIBUTION. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?

What's in COLUMBIA's tap water

Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving COLUMBIA.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 38.3 ppb, 638x above the EWG health guideline of 0.06 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 47.0 ppb, 313x above the EWG health guideline of 0.15 ppb.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic acids (HAA5) detected at 27.6 ppb, 276x above the EWG health guideline of 0.1 ppb.

Recommended filters for COLUMBIA

Filters matched to the specific contaminants in COLUMBIA's water supply.

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

All contaminants detected in COLUMBIA's tap water

Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →

Contaminant Detected EWG
US health-based
EPA
US legal
EU DWD
Europe
WHO
global
CA PHG
strictest US
Tested
sample year
Status
Haloacetic acids (HAA9)
Disinfection byproduct
38.3 ppb 0.06 638× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
47.0 ppb 0.15 80.0 100 313× over
Haloacetic acids (HAA5)
Disinfection byproduct
27.6 ppb 0.1 60.0 60 276× over
Chromium (hexavalent)
Heavy metal
0.0263 ppb 0.02 1.3× over
Chlorate
Disinfection byproduct
61.8 ppb 210.0 Below guideline
Manganese
Heavy metal
0.775 ppb 100.0 50 80 Below guideline
Perfluoropentanoic Acid (PFPeA)
PFAS
1.24 ppt 1000.0 Below guideline
Perfluorohexanoic Acid (PFHxA)
PFAS
0.425 ppt 1000.0 Below guideline
Strontium
Radiological
0.0715 ppb 1500.0 Below guideline
4-Androstene-3,17-dione
Other
0.082 ppt Below guideline

All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.

Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.

Treatment plant contact info

For service issues, water quality concerns, or to request a Consumer Confidence Report from HOWARD COUNTY D.P.W. DISTRIBUTION.

ZIP codes served

COLUMBIA's public water systems serve the following ZIP codes: