01The verdict: is Petersburg water safe?
Petersburg's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (86.3/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 3,218 residents using surface water (rivers, lakes, or reservoirs).
2 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 ↓Lead is well under the limit
90th-percentile lead is 3.5 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓3 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 ↓Petersburg's drinking water received a grade of A- (86.3 out of 100), indicating good water quality. The city's 1 water system serves approximately 3,218 residents using surface water.
Lead levels were measured at 3.5 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 48 violations on record, including 4 health-based violations. 2 remain unresolved.
Petersburg ranks #4 out of 73 cities in Alaska for water quality, placing it one of the best 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. As a small community water system, Petersburg may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
02What's in Petersburg's water
Every contaminant flagged in Petersburg, 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.
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. | 3.5 | 15 | ppb | Inorganic | Safe |
Cities ranked by 90th-percentile lead PF PFAS in Alaska
Cities ranked by compounds detected Cu Copper in Alaska
Cities ranked by 90th-percentile copper
03Petersburg'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 48 violations on record, including 4 health-based violations. 2 remain unresolved.
9 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.
▼ Down 7.5 ppb since 1997. Latest reading: 3.5 ppb (2024) — 23% of the action level. Sampled at higher-risk homes (90th percentile).
04Where Petersburg's water comes from
Petersburg's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface Water
Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.
Local treatment
Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.
1 system
1 water system, operated under native american ownership.
3,218 people
Residents served across Petersburg'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 native american ownership and serves approximately 3,218 people through 1 water system.
| System name | PWSID | Population | Source |
|---|---|---|---|
| PETERSBURG | AK2130148 | 3,218 | Surface Water |
05How Petersburg compares
Scores for nearby Alaska cities on one line, with the average marked.
dashed line = Alaska average (61/100)
Petersburg scores 86.3/100 — above the Alaska average of 61/100. It outscores 9 of 10 nearby cities. Full Alaska rankings →
38.5 / 100FFairbanks, AK
38.4 / 100CJuneau, AK
65.4 / 100AElmendorf Air Force Base, AK
94.2 / 100FWasilla, AK
42.5 / 100BFort Richardson, AK
81.6 / 100
06What to do at home
Steps matched to what testing actually found in Petersburg's water — not generic advice.
A basic carbon filter still helps
Petersburg's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.
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 Petersburg 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 Petersburg, AK tap water safe to drink?
Petersburg's water quality earned a grade of A- (86.3/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #4 out of 73 cities tested in Alaska.
What contaminants are in Petersburg's water?
Lead was measured at 3.5 ppb (90th percentile). 48 violations are on record.
How is Petersburg'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 Petersburg?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Petersburg's water come from?
Petersburg's water is sourced from Surface water. The city has 1 water system serving approximately 3,218 residents.
What health violations has Petersburg's water system had?
Petersburg has 4 health-based violations on record. The most recent violation was recorded in August 2024. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.
How does Petersburg's water compare to other cities?
Petersburg ranks #4 out of 73 cities in Alaska (better than 95% of state cities) and #4728 out of 15382 cities nationally (69th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Petersburg's small water system affect quality?
Petersburg's system serves approximately 3,218 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 48 violations on record.