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Rockville Drinking Water Quality

What's Really in Your Tap Water?

Rockville tap water is generally safe, though there are a few things worth knowing. With 137 ppm hardness (8 gpg), expect some mineral deposits over time. Lead levels test well below the EPA action level. There have been 60 violations recorded over the past 3 years.

B

Generally Safe

Minor compliance issues

8 GPG hardness

Lead

Below EPA action level

0ppb
EPA Limit

EPA action level: 15 ppb

Hardness

Hard water

137ppm
0100300+

US Average: 100 ppm

Violations

Past 3 years

60total

All administrative/monitoring

View EPA report →

Is Rockville Tap Water Safe to Drink?

Rockville tap water meets EPA health standards, but the water utility has administrative compliance issues.

  • •No health-based violations in the past 3 years.
  • •Lead levels are below the EPA action level.
  • •60 monitoring/reporting violations (administrative issues like missed testing deadlines or late reports).
  • •While not directly health-related, frequent administrative violations may indicate operational issues with the water utility.
  • •We recommend testing your water at home for complete peace of mind.

The data below shows test results from 1 water utility serving 52K people in the Rockville area. Water quality testing is conducted regularly and reported to the EPA.

How Hard is Rockville Water?

SoftVery Hard
060120180300+

137 ppm

8 grains per gallon

Hard

Hard water can cause scale buildup in pipes and appliances. A water softener may be beneficial.

Impact on Your Home

Shower

May dry out skin & hair

Kitchen

Spots on dishes

Laundry

Clothes may feel stiff

Appliances

Scale buildup

Regional Comparison

Rockville
137
Maryland
130
US Average
100

Values in ppm (mg/L as CaCO₃)

Based on 3 water samples from Montgomery County.

Your pipes tell a different story

The data above shows what leaves the treatment plant—not what comes out of your faucet. Old pipes, lead solder, and building plumbing can add contaminants the city never tests for. Know exactly what's in your Rockville tap water.

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Water splashing from a kitchen faucet

Lead & Contaminants

Understanding lead levels and water quality violations in Rockville

Lead Test Results

90th Percentile Lead Level

0 ppb

Below EPA Action Level
0EPA Limit (15)30+

Rockville lead levels are well within safe limits.

Regular testing is still recommended, as lead can enter water through household plumbing.

Last sampled: 2018-06-30

About Lead in Drinking Water

What is Lead in Water?

Lead is a toxic metal that can dissolve into drinking water from older pipes, solder, and fixtures. It's invisible, tasteless, and odorless, making testing the only way to detect it. The EPA has set an action level of 15 ppb, though they emphasize there is no safe level of lead exposure.

Potential Health Effects

Children

Developmental delays, learning difficulties, lower IQ, behavioral issues

Adults

High blood pressure, kidney damage, reproductive issues

How to Reduce Exposure

  • •Run water for 30 seconds to 2 minutes before drinking, especially in the morning
  • •Use cold water for cooking and drinking (hot water dissolves more lead)
  • •Install a NSF-certified filter designed to remove lead
  • •Test your water, especially if your home was built before 1986

EPA Compliance History

Active Violations

Administrative issues pending

Current violations are administrative or monitoring-related. Water quality is not immediately affected, but stay informed about utility updates.

3-Year Violation Summary

60

Total Violations

0

Health-Related

60

Administrative

Active violations pending resolution

Health-Related Violations

Contaminant exceeded EPA safety limits. May require filter or alternative water source.

Administrative Violations

Missed testing deadlines or reporting. Does not indicate water quality issues.

View Full EPA Compliance Report for Rockville

Who Provides Rockville's Water?

Utility Name

CITY OF ROCKVILLE

EPA System ID (PWSID)

MD0150003

Primary Water Source

Surface Water

Population Served

52K

View Full EPA Report

Frequently Asked Questions

Common questions about Rockville tap water quality

Rockville tap water is generally safe to drink with minor compliance issues. While there may be some monitoring violations, there are no significant health-based concerns. The water meets EPA safety standards.
Rockville has hard water with a hardness of 137 ppm (8 grains per gallon). Hard water can cause scale buildup in pipes and appliances. A water softener may be beneficial.
Lead levels (0 ppb) are below the EPA action level of 15 ppb.
Rockville's tap water is provided by CITY OF ROCKVILLE. The EPA system ID (PWSID) is MD0150003. The primary water source is Surface Water. You can find official water quality reports and contact information through your local utility.
Based on recent water quality data, a water filter may be beneficial in Rockville. The water is hard (137 ppm), so a water softener could reduce scale buildup in pipes and appliances.
Rockville's water utility has had 60 violations in the past 3 years. Of these, 0 were health-based and 60 were monitoring/reporting related.
Rockville's water utility uses chlorine or chloramine to disinfect the water supply. This is a safe and common practice required by the EPA. The taste is usually more noticeable in warm weather or near treatment facilities. To reduce chlorine taste, let water sit in an open pitcher for 30 minutes, use a refrigerator filter, or install a carbon filter on your tap.
Rockville's tap water primarily comes from surface water sources. Surface water is collected from rivers, lakes, and reservoirs, then treated before distribution. The water is provided by CITY OF ROCKVILLE.

Nearby Cities in Maryland

Baltimore

Glen Burnie-broadneck

Moderate water

Hagerstown

Very Hard water

Crofton-odenton

Moderate water

Fort George G. Meade

Moderate water

Frederick

Moderate water

View all Maryland cities

This data is for informational purposes only. Water quality can vary by neighborhood and building. For official reports, contact your local water utility or the EPA. Learn about our methodology