01The verdict: is Chalan Lau Lau water safe?
Chalan Lau Lau's drinking water has significant quality concerns based on EPA testing data. With a grade of D (48.3/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,522 residents using groundwater (wells).
11 unresolved violations on record
EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.
See what was cited ↓2K people, 2 systems
All figures on this page come from federal EPA compliance and testing data for the systems serving this city.
See the systems ↓Lead is approaching its limit
Measured at 14.8 ppb — 99% of the 15 ppb limit. Within the rules, but with less headroom than you'd want.
See the ledger ↓Chalan Lau Lau's drinking water received a grade of D (48.3 out of 100), indicating poor water quality. The city's 2 water systems serve approximately 1,522 residents using groundwater.
Lead levels were measured at 14.8 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 91 violations on record, including 4 health-based violations. 11 remain unresolved.
Chalan Lau Lau ranks #6 out of 7 cities in Northern Mariana Islands for water quality, placing it below average in the state. Chalan Lau Lau 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. While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection. As a small community water system, Chalan Lau Lau may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities. The system has seen 17 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
02What's in Chalan Lau Lau's water
Every contaminant flagged in Chalan Lau Lau, 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.
Near Limit — EPA Action Level: 15 ppb
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb — no lead level is considered safe for children. An NSF 53-certified filter provides additional protection, and running the cold tap 30 seconds after stagnation reduces exposure.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. | 14.8 | 15 | ppb | Inorganic | Near Limit |
03Chalan Lau Lau'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 91 violations on record, including 4 health-based violations. 11 remain unresolved.
3 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▲ Up 14 ppb since 2013. Latest reading: 15 ppb (2025) — 99% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Chalan Lau Lau's water comes from
Chalan Lau Lau's drinking water is drawn from underground aquifers through wells.
Groundwater
Underground aquifers reached by wells — naturally filtered, but can carry minerals like arsenic and nitrate.
Local treatment
Groundwater generally needs less treatment — typically disinfection and, where needed, mineral removal.
2 systems
2 water systems, operated under private ownership.
1,522 people
Residents served across Chalan Lau Lau's service area.
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 private ownership and serves approximately 1,522 people through 2 water systems.
| System name | PWSID | Population | Source |
|---|---|---|---|
| Star Water | MP0000160 | 1,522 | Groundwater |
| Saipan Vegas | MP0000030 | 100 | Groundwater |
05How Chalan Lau Lau compares
Scores for nearby Northern Mariana Islands cities on one line, with the average marked.
dashed line = Northern Mariana Islands average (60/100)
Chalan Lau Lau scores 48.3/100 — below the Northern Mariana Islands average of 60/100. It outscores 1 of 6 nearby cities.
40.2 / 100BLower Base, MP
73.4 / 100DSan Jose, MP
50 / 100BSinapalu, MP
78.2 / 100CAs Matuis, MP
68.4 / 100DSan Antonio, MP
50.9 / 100
06What to do at home
Steps matched to what testing actually found in Chalan Lau Lau's water — not generic advice.
Filter drinking & cooking water
NSF-certified water filter. Lead detected at 14.8 ppb
Compare tested filters →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 →Watch for Chalan Lau Lau 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 Chalan Lau Lau, MP tap water safe to drink?
Chalan Lau Lau's water quality earned a grade of D (48.3/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #6 out of 7 cities tested in Northern Mariana Islands.
What contaminants are in Chalan Lau Lau's water?
Lead was measured at 14.8 ppb (90th percentile). 91 violations are on record.
How is Chalan Lau Lau'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 Chalan Lau Lau?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Chalan Lau Lau's water come from?
Chalan Lau Lau's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,522 residents.
What health violations has Chalan Lau Lau's water system had?
Chalan Lau Lau has 4 health-based violations on record. The most recent violation was recorded in May 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 11 violations remain unresolved.
Is Chalan Lau Lau's groundwater at risk of contamination?
Chalan Lau Lau 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 91 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 Chalan Lau Lau's water compare to other cities?
Chalan Lau Lau ranks #6 out of 7 cities in Northern Mariana Islands (better than 14% of state cities) and #13206 out of 15382 cities nationally (14th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.