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WaterVerge

Water quality report · updated Jul 2026

Is Adjuntas, PR Tap Water Safe to Drink?

Graded F — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do ↓

1 contaminant over a legal limit
5.0 ppb lead, 90th percentile · low
91 unresolved violations
11K people served by 17 water systems

PWSID PR0004584 · high data confidence · local government utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
F 44 / 100

#64 of 101Puerto Rico cities
How we grade →

01The verdict: is Adjuntas water safe?

Adjuntas's drinking water has significant quality concerns based on EPA testing data. With a grade of F (44/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 17 water systems serve approximately 10,987 residents using surface water (rivers, lakes, or reservoirs).

The concern

Copper is over its legal limit

Measured at 1.83 mg/L against the EPA Action Level of 1.3 mg/L. The ledger below shows how far over — and which filter removes it.

See the measurement ↓
The good news

Lead is well under the limit

90th-percentile lead is 5.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

266 violations in the last five years

Recent compliance history is the best predictor of future problems — the year-by-year record is below.

See the record ↓

Adjuntas's drinking water received a grade of F (44 out of 100), indicating failing water quality. The city's 17 water systems serve approximately 10,987 residents using surface water.

Lead levels were measured at 5.0 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals. The system has 2239 violations on record, including 653 health-based violations. 91 remain unresolved.

Adjuntas ranks #64 out of 101 cities in Puerto Rico for water quality, placing it below average in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. The system has seen 266 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

How the 44/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
0 / 45F
Lead & CopperLead at 5.0 ppb (90th percentile).
14 / 20C
ContaminantsNo PFAS compounds detected.
16 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
10 / 10A
Source RiskWater source: Surface water.
4 / 5B

02What's in Adjuntas's water

Every contaminant flagged in Adjuntas, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.

2 detections · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%

Over Limit — EPA Action Level: 1.3 mg/L

Exceeds the EPA action level. Copper leaches from household plumbing — flush taps for 30 seconds before drinking, and consider a certified filter.
Exceeds Limit What to do →
32 contaminants tested under EPA SDWIS, LCR and UCMR programs · 2 detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 5.0 15 ppb Inorganic Safe
Copper (90th percentile) 1.83 1.3 mg/L Inorganic Over Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium ND HI µg/L PFAS Not Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03Adjuntas's ten-year track record

Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 2239 violations on record, including 653 health-based violations. 91 remain unresolved.

1 of the last ten years was clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.

17 health-based in 10 yrs 330 monitoring & paperwork 51 still unresolved
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Adjuntas's water quality assessment. Grade: F (44/100).
Violation6 drinking water violations recordedContaminants: Revised Total Coliform Rule.Resolved
Violation6 drinking water violations recordedContaminants: Revised Total Coliform Rule.Resolved
Violation6 drinking water violations recordedContaminants: Revised Total Coliform Rule.Resolved
Lead, 90th percentileppb · lower is better
05101520EPA action level · 15 ppb1992 — 6 ppb1993 — 8 ppb2000 — 3 ppb2001 — 2.5 ppb2002 — 1 ppb2003 — 4.8 ppb2004 — 1.4 ppb2005 — 2 ppb2006 — 2 ppb2007 — 4 ppb2009 — 6 ppb2012 — 6 ppb2015 — 6 ppb2016 — 6 ppb2017 — 3 ppb2018 — 3 ppb2021 — 6 ppb2023 — 3 ppb63199220022006201520212023

Down 3 ppb since 1992. Latest reading: 3 ppb (2023) — 20% of the action level. Sampled at higher-risk homes (90th percentile).

Copper, 90th percentilemg/L

1.8mg/L(2012)

One sampling round on record — 141% of the 1.3mg/L EPA action level. Sampled at higher-risk homes (90th percentile).

04Where Adjuntas's water comes from

Adjuntas's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Source

Surface Water

Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.

Treatment

Local treatment

Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.

Distribution

17 systems

17 water systems, operated under local government ownership.

Delivery

10,987 people

Residents served across Adjuntas's service area.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by local government ownership and serves approximately 10,987 people through 17 water systems.

System namePWSIDPopulationSource
GARZAS PR0004584 3,402 Surface Water
ADJUNTAS URBANO PR0004204 2,846 Surface Water
YAHUECAS PR0004684 2,646 Surface Water
GUILARTE PR0004494 1,220 Surface Water
SALTILLO VACA PR0004134 804 Groundwater
JUAN GONZALEZ PR0401284 500 Groundwater
ACUEDUCTO GARZAS JUNCOS PR0401234 460 Groundwater
COMUNIDAD JUAN HERNANDEZ PR0401074 300 Groundwater
PELLEJAS PR0401034 295 Groundwater
ASOC. VEC. COM. HELECHALES PR0401024 263 Groundwater
ASOCIACION ACUEDUCTO REVENTON PR0401294 212 Surface Water
ACUEDUCTO COMUNITARIO SOSTENIBLE, INC PR0401384 171 Groundwater
LIMANI PR0401144 150 Groundwater
ADJUNTAS LAS CRUCES, INC PR0401014 130 Groundwater
COMUNIDAD PALOMO PR0401064 120 Groundwater
COM. GARZAS CENTRO AEROPUERTO PR0401374 84 Groundwater
ASOC. DE RESIDENTES CAMINO PAGAN INC PR0401394 30 Groundwater

Water bodies near Adjuntas

Lago Garzas Nr Adjuntas · lake Rio Grande De Arecibo Nr Adjuntas · river Lago Adjuntas · lake Rio Grande De Arecibo · river Lago Vivi · lake

As a surface-water system, these water bodies may directly influence Adjuntas's drinking water supply.

05Pressure on Adjuntas's watershed

Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.

Drought

D1 — moderate drought

Adjuntas Municipio is in D1 (moderate drought) per the U.S. Drought Monitor (week of Jul 2026). Drought can raise disinfection-byproduct levels and taste/odor issues as utilities draw from lower reservoirs.

06How Adjuntas compares

Scores for nearby Puerto Rico cities on one line, with the average marked.

Adjuntas (this city)
44 · F
Mayaguez
42.1 · F
San Juan
38.5 · F
Toa Alta
38.5 · F
Aguadilla
38.3 · F
Ponce
34.9 · F

dashed line = Puerto Rico average (39/100)

Adjuntas scores 44/100on par with the Puerto Rico average of 39/100. It outscores 10 of 10 nearby cities.

Adjuntas Municipio water quality rankings
Compare all cities in the county — grades, violations, and contaminant data side by side.

07What to do at home

Steps matched to what testing actually found in Adjuntas's water — not generic advice.

Because of copper

Filter drinking & cooking water

NSF-certified water filter. Copper exceeds the EPA action level of 1.3 mg/L

Compare tested filters →
Because lead was detected

Flush taps & check your service line

Lead leaches from pipes as water sits. Run cold water 30 seconds before drinking (especially mornings), and ask the utility whether your address still has a lead service line.

Lead risks explained →
Stay informed

Watch for Adjuntas alerts

We refresh EPA data monthly and surface new violations, advisories, and boil-water notices for your county on this page.

All water alerts →

Frequently asked questions

Is Adjuntas, PR tap water safe to drink?

Adjuntas's water quality earned a grade of F (44/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #64 out of 101 cities tested in Puerto Rico.

What contaminants are in Adjuntas's water?

Lead was measured at 5.0 ppb (90th percentile). No PFAS compounds were detected. 2239 violations are on record.

How is Adjuntas's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Adjuntas?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Adjuntas's water come from?

Adjuntas's water is sourced from Surface water. The city has 17 water systems serving approximately 10,987 residents.

What health violations has Adjuntas's water system had?

Adjuntas has 653 health-based violations on record. The most recent violation was recorded in December 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 91 violations remain unresolved.

How does Adjuntas's water compare to other cities?

Adjuntas ranks #64 out of 101 cities in Puerto Rico (better than 37% of state cities) and #14144 out of 15382 cities nationally (8th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

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About Adjuntas, PR: Median household income $17,752 · median home value $102,315 · median age 42 · 54% homeowners. Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.