Is Sinapalu, MP Tap Water Safe to Drink?
Graded B, with 17 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
78.2/100
waterverge.com Sinapalu, MP — Water Quality Report
Sinapalu's drinking water received a grade of B (78.2 out of 100), indicating good water quality. The city's 2 water systems serve approximately 2,730 residents using groundwater.
Lead levels were measured at 0.9 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 26 violations on record, including 4 health-based violations. 17 remain unresolved.
What to know about Sinapalu's water
Sinapalu ranks #1 out of 7 cities in Northern Mariana Islands for water quality, placing it one of the best in the state.
Sinapalu relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Sinapalu may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Sinapalu, MP water safe to drink?
Sinapalu's drinking water has significant quality concerns based on EPA testing data. With a grade of B (78.2/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 2,730 residents using groundwater (wells).
Recent water quality updates for Sinapalu
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Sinapalu's water quality assessment. Grade: B (78.2/100).
Contaminants: Revised Total Coliform Rule.
Contaminants: Revised Total Coliform Rule.
1 health-based. Contaminants: Public Notice, Groundwater Rule.
Key contaminant findings
Based on the most recent EPA sampling data for Sinapalu's water supply.
Well within EPA limits.
Violation history
Sinapalu's water system has 26 total violations on record, including 4 health-based violations. 17 remain unresolved. 4 violations were issued in the last 5 years.
Where does Sinapalu's water come from?
Sinapalu's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 2,730 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Sinapalu residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Sinapalu's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.9 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Sinapalu compares by contaminant
Explore where Sinapalu ranks among all Northern Mariana Islands cities for specific contaminants.
Water source & infrastructure
Where Sinapalu's water comes from
Sinapalu's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by state ownership and serves approximately 2,730 people through 2 water systems.
Water systems serving Sinapalu
| System Name | PWSID | Population | Source |
|---|---|---|---|
| Commonwealth Utilities Corp (Rota) | MP0000003 | 2,504 | GW |
| Rota Crystal | MP0000165 | 226 | GWP |
How Sinapalu compares
Full Northern Mariana Islands rankings →Sinapalu's score of 78.2/100 is above the average of 55/100 among major Northern Mariana Islands cities. It outscores 6 of 6 nearby cities.
Nearby cities
View Northern Mariana Islands rankings →About Sinapalu, MP
Wikipedia →Saipan is the largest island and capital of the Northern Mariana Islands, an unincorporated territory of the United States in the western Pacific Ocean. According to 2020 estimates by the United States Census Bureau, the population of Saipan was 43,385. Its people have been United States citizens since the 1980s. Saipan is one of the main homes of the Chamorro and the Carolinian, the indigenous people of the Mariana Islands.
Learn more about your water
Guides and resources related to Sinapalu's water quality findings.
Frequently asked questions
Is Sinapalu, MP tap water safe to drink?
Sinapalu's water quality earned a grade of B (78.2/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #1 out of 7 cities tested in Northern Mariana Islands.
What contaminants are in Sinapalu's water?
Lead was measured at 0.9 ppb (90th percentile). 26 violations are on record.
How is Sinapalu'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 Sinapalu?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Sinapalu's water come from?
Sinapalu's water is sourced from Groundwater. The city has 2 water systems serving approximately 2,730 residents.
What health violations has Sinapalu's water system had?
Sinapalu has 4 health-based violations on record. The most recent violation was recorded in February 2023. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 17 violations remain unresolved.
Is Sinapalu's groundwater at risk of contamination?
Sinapalu uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 26 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Sinapalu's water compare to other cities?
Sinapalu ranks #1 out of 7 cities in Northern Mariana Islands (better than 86% of state cities) and #8758 out of 15744 cities nationally (44th percentile). The grade of B reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.