Water Quality Report · Updated May 12, 2026

HOWARD COUNTY D.P.W. DISTRIBUTION

Serving 286,158 residents in COLUMBIA, Maryland .

National rank 94th percentile
Maryland rank 75th percentile
Data confidence Medium
Quick answer

HOWARD COUNTY D.P.W. DISTRIBUTION delivers tap water graded B (78/100) by TapWaterSafety.org. The utility serves approximately 286,158 residents in COLUMBIA, Maryland using surface water (purchased). 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. For questions, the utility can be reached at 410-313-4974.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
286,158
People served
1
City served
10
Contaminants detected
4
Above health guidelines
0
EPA violations (5 yr)

Is COLUMBIA tap water safe to drink?

HOWARD COUNTY D.P.W. DISTRIBUTION delivers tap water that earns a grade of B (78/100) from TapWaterSafety.org — a good rating, with only minor concerns relative to health-based guidelines.

The utility serves 286,158 residents in COLUMBIA, drawing from surface water (purchased).

Public testing data identifies 4 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Chromium (hexavalent). For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for HOWARD COUNTY D.P.W. DISTRIBUTION.

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.

Contact HOWARD COUNTY D.P.W. DISTRIBUTION

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for COLUMBIA

Filters matched to the specific contaminants in this water supply.

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

Score breakdown

This utility's overall score of 78/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
23 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
18 / 20
Compliance History
10 / 10
Source Water Vulnerability
7 / 10

Contaminants detected — international standards comparison

Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

HOWARD COUNTY D.P.W. DISTRIBUTION service area

This water system serves 1 community in Howard County, Maryland. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
MD0130002
Owner type
Local government
Source water
Surface water (purchased)
Service connections
79,084
Service area
COLUMBIA, Howard County, Maryland