ZipCheckup grade for 21770: C.
A mixed picture - some signals here are worth your attention.
Your top priority: test this home for radon. Check your ZIP → EPA radon map
Monrovia, MD (21770): PFAS Detected in Mapped Water Systems - 66/100
EPA data combined for 4 water systems mapped to this ZIP (largest mapped system: New Design - Frederick County)
EPA records for the water systems mapped to 21770 in Monrovia, MD contain 2 recorded violations for inclusive record years 2021 through 2026, all mapped systems combined; 0 are marked health-based.
Data source: U.S. Environmental Protection Agency (EPA) SDWIS
At a Glance
- Water EPA records for water systems mapped to this ZIP show 2 violations (non-health) (since 2021).
- Lead The reported 90th-percentile lead result of 0.003 mg/L is below the EPA action level for water systems; EPA's health goal for lead is zero.
- PFAS PFAS detected in UCMR5 sampling; see the PFAS section for each compound, compared with the federal PFAS MCL where one exists.
- Radon EPA Zone 1 - highest county-level potential. This is not a home measurement; test before any threshold comparison.
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Looking at every monitored dimension for 21770 in Monrovia, the high-priority label applies to 1 condition - nothing in the record clears the bar for critical status.
Score Breakdown
Overall Home Safety Score: 66/100
This is the published model score. Component and domain values are shown independently; they are not added together on this page.
Canonical components
Required domains
Coverage: 4 of 4 components and 3 of 3 domains observed.
Model 4.0.0; series home-safety-v4-cross-vertical.
Safety & Health (8) HIGH
Your Water System
ZIP code 21770 in Monrovia, Maryland is mapped to the water system New Design - Frederick County (EPA ID: MD0100030). This system provides water to approximately 74,911 people from surface water sources.
There are 4 community water systems serving this area.
Water Systems Serving This Area
| System Name | EPA ID | Population | Source |
|---|---|---|---|
| New Design - Frederick County | MD0100030 | 74,911 | Surface water |
| Sam Hill Estates | MD0100040 | 1,036 | Groundwater |
| Knolls of Windsor | MD0100041 | 1,553 | Surface water |
| Bradford Estates | MD0100032 | 178 | Groundwater |
Other Water Quality Reports in Maryland
- 20588 (Dhs)
- 20601 (Waldorf) - 3 violations recorded for mapped water systems
- 20602 (Waldorf) - 3 violations recorded for mapped water systems
- 20603 (Waldorf) - 3 violations recorded for mapped water systems
- 20604 (Waldorf)
- 20606 (Abell)
- 20607 (Accokeek) - 3 violations recorded for mapped water systems
- 20608 (Aquasco)
- 20609 (Avenue)
- 20610 (Barstow)
- 20611 (Bel Alton) - 3 violations recorded for mapped water systems
- 20612 (Benedict)
- 20613 (Brandywine) - 2 violations recorded for mapped water systems
- 20615 (Broomes Island)
- 20616 (Bryans Road) - 1 violation recorded for mapped water systems
- 20617 (Bryantown)
- 20618 (Bushwood)
- 20619 (California) - 12 violations recorded for mapped water systems
- 20620 (Callaway) - 1 violation recorded for mapped water systems
- 20621 (Chaptico) - 4 violations recorded for mapped water systems
Nearby Water Quality Reports
- 21754 (Ijamsville) - 3 mi - 2 violations recorded for mapped water systems
- 21774 (New Market) - 4 mi - 2 violations recorded for mapped water systems
- 21771 (Mount Airy) - 5 mi - 6 violations recorded for mapped water systems
- 20872 (Damascus) - 6 mi
- 21704 (Frederick) - 7 mi - 2 violations recorded for mapped water systems
- 20871 (Clarksburg) - 8 mi
- 21701 (Frederick) - 8 mi - 3 violations recorded for mapped water systems
- 21762 (Libertytown) - 9 mi
- 21792 (Unionville) - 9 mi
- 21765 (Lisbon) - 10 mi
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for New Design - Frederick County (MD0100030) on EPA.gov.
4 of the top compounds applied across the surrounding county in USGS pesticide-use estimates appear on EPA drinking-water monitoring lists. See the agricultural pesticide-use section.
PFAS Contamination Detected
PFAS ("forever chemicals") have been reported in samples from water systems associated with ZIP code 21770.
Detected compounds: PFPeA.
Highest measured level: 0.0033 µg/L
Reverse osmosis (RO) and activated carbon block filters can reduce PFAS at the tap. Certifications list the compounds covered: an NSF/ANSI 53 or 58 claim for PFOA/PFOS does not cover every PFAS, so check that the product lists the compounds detected here.
Environmental Hazards (10) MODERATE
Home & Infrastructure (8) MODERATE
Cost & Community (8) HIGH
CPSC product recall notices
These national notices are not matched to this ZIP code or water system.
Protect Your Home in Monrovia
Based on local data for ZIP 21770, these services may benefit homeowners in your area.
Based on local data for your area. Use the tools below to explore your options.
Gutter Installation & Repair
The median home in 21770 was built around 1981. Aging gutters can cause foundation damage, basement flooding, and mold - a professional assessment can prevent costly repairs.
Typical cost: Gutter installation: typically $1,000–$2,500 for a standard home
Estimate Your Home Maintenance CostsWindow Replacement
The median build year of homes in Monrovia is 1981; check the age and condition of your own windows. ENERGY STAR windows can save $101–$583/year on energy bills.
Typical cost: Window replacement: typically $300–$800 per window installed
Estimate Your Home Maintenance CostsService recommendations are based on public data for this ZIP code (FEMA, Census ACS, NWS). Actual needs vary by property. By calling, your information will be shared with an independent service provider. ZipCheckup may receive compensation. Cost estimates are approximate and vary by property, condition, and contractor.
Frequently Asked Questions
Is the tap water in 21770 safe to drink?
EPA SDWIS records 2 violations since 2021 across the water systems mapped to ZIP 21770 (primary system: New Design - Frederick County), including 0 health-based. The violation table above shows which system each record belongs to. ZipCheckup last updated this page in July 2026. The federal source release date is unavailable, so that month is not presented as source currency.
Where does 21770's water come from?
The recorded water source for New Design - Frederick County, a system mapped to ZIP code 21770, is Surface water. This system serves approximately 74,911 people.
How does Monrovia water compare to the national average?
Monrovia's Home Safety Score ranks lower than 71% of U.S. ZIP codes, and lower than 59% of ZIP codes within Maryland.
How can I get my water tested in Monrovia?
If New Design - Frederick County supplies your home, contact it for its Consumer Confidence Report; otherwise contact the water utility that serves your address, or hire a certified lab for independent home water testing. The EPA recommends annual testing if you use a private well.
Is lead a concern in 21770 tap water?
The Lead and Copper Rule record selected for 21770 reports a 90th-percentile lead result of 0.003 mg/L for a water system mapped to this ZIP (record date 2019-12-31). The EPA action level is 0.015 mg/L. This result is below the EPA action level; it does not show the lead level in each home.
What is the radon risk for 21770?
21770 is mapped to a county in EPA Radon Zone 1 (high county-level radon potential; EPA recommends testing every home), located in Frederick County. EPA radon zones range from Zone 1 (highest county-level potential) to Zone 3 (lowest). Testing your home is recommended regardless of zone.
Are there PFAS (forever chemicals) in 21770's water?
Yes, PFAS have been detected in samples from water systems mapped to 21770. Reverse osmosis and activated carbon filters certified to NSF/ANSI 53 or 58 specifically for PFOA/PFOS reduction can reduce PFAS.
How to cite this page
ZipCheckup. (2026). Monrovia, MD (21770): PFAS Detected in Mapped Water Systems - 66/100. https://zipcheckup.com/report/21770/
@misc{zipcheckup-report-21770,
author = {{ZipCheckup}},
title = {{Monrovia, MD (21770): PFAS Detected in Mapped Water Systems - 66/100}},
year = {2026},
url = {https://zipcheckup.com/report/21770/}
}
Page version: October 2026.
Nearby ZIP Code Reports
Water quality comparison for ZIP codes near 21770
| ZIP Code | City, State | Distance | Grade | Violations |
|---|---|---|---|---|
| 21754 | Ijamsville, MD | 3.0 mi | C | 2 |
| 21774 | New Market, MD | 4.3 mi | C | 2 |
| 21771 | Mount Airy, MD | 4.8 mi | D | 6 |
| 20872 | Damascus, MD | 5.5 mi | C | 0 |
| 21704 | Frederick, MD | 7.2 mi | C | 2 |
| 20871 | Clarksburg, MD | 7.9 mi | C | 0 |
| 21701 | Frederick, MD | 8.0 mi | C | 3 |
| 21762 | Libertytown, MD | 9.1 mi | N/A | 0 |
| 21792 | Unionville, MD | 9.2 mi | N/A | 0 |
| 21765 | Lisbon, MD | 9.5 mi | N/A | 0 |
Nearby ZIP Code Reports
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