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County water report

Kalawao County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Kalawao County, Hawaii.

Water grade

N/A

Water score

N/A

State rank

N/A

Health violations

N/A

EPA SDWIS, 5-year lookback

Watershed impaired

Not reported

EPA ATTAINS coverage varies by state

Monitoring sites

80

4,221 recent measurements

Live streamflow

69%

Waikolu Str blw pipe nr Kalaupapa, Molokai, HI

Water at a glance

Key Water Indicators for Kalawao County

EPA SDWIS

Safety Grade

N/A

Insufficient data

EPA SDWIS

Active Violations

N/A

5-year health-based lookback

EPA ATTAINS

Watershed Health

Not reported

Coverage varies by state

USGS NWIS

Streamflow Snapshot

69% of mean

Waikolu Str blw pipe nr Kalaupapa, Molokai, HI

EPA WQP

Monitoring Sites

80

4,221 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Editorial analysis

Understanding Kalawao County’s Water

Drinking Water Quality Overview

EPA SDWIS

Kalawao County has limited drinking water data on file. Violation data are unavailable for this county.

River & Streamflow Status

USGS NWIS

USGS NWIS gauge data (as of 2026-05-14T09:05:00.000-10:00) puts Waikolu Str blw pipe at 12.2 cfs — running somewhat below its historical average at 69% of mean. Streamflow is a leading indicator of drought stress, sediment load, and dilution capacity: low flows concentrate pollutants and warm water temperatures, stressing aquatic life and, in surface-water-dependent systems, the source water quality for treatment plants.

Monitoring Network

EPA WQP

EPA's Water Quality Portal (WQP) aggregates monitoring data from federal, state, and tribal agencies. Kalawao County has extensive coverage with 80 active monitoring sites with 4,221 recent measurements on record. Predominant monitoring categories include physical and nutrient. More monitoring sites generally indicate greater scientific attention to local water conditions — and provide the baseline data that regulators use to set future impairment listings.

Editorial advisory

What the data suggests for Kalawao County

Water Verdict

Kalawao County, Hawaii does not have sufficient EPA SDWIS water quality data to determine an overall assessment. Residents should contact their local water utility for the most recent Consumer Confidence Report. The county's primary USGS gauge drains roughly 4 square miles of upstream watershed, giving local source waters a regional footprint. At the most recent USGS reading, local streamflow was below its historical mean at 68.8% — worth watching in drier seasons.

Violation Context

Health-based violation data is not available for Kalawao County, Hawaii. EPA health violations occur when water systems exceed allowable contaminant levels or fail to meet treatment requirements. Residents should request the latest Consumer Confidence Report from their water provider. For independent context, 4,221 water-quality monitoring results have been recorded across the county in the EPA Water Quality Portal over the past five years.

Consumer Guidance

Drinking-water compliance data is not yet available for Kalawao County in the EPA SDWIS system, which is common for rural areas and census areas served by private wells or small tribal systems. Residents should contact their local utility or state drinking-water agency for the most current Consumer Confidence Report. Using an NSF-certified filter (look for certifications against ANSI/NSF 53 or 58) can provide additional safety margin for any unconfirmed contaminants. A pipeline streamflow snapshot from the Waikolu Str blw pipe gauge is also available on this page.

Regional Context

State-level water quality comparison data is not available for Kalawao County. When data is available, this section will show how the county's water quality compares to other counties in Hawaii.

Advisory text summarizes county-level public records and is not a replacement for your utility's current Consumer Confidence Report or direct local notices.

Past 5 years

Water Quality Monitoring

Monitoring Sites

80

Active in the past 5 years

Measurements Recorded

4.2K

4,221 total readings

Most Measured

  • Physical
  • Nutrient
  • Biological, Algae, Phytoplankton

Categories measured most frequently

Data from the EPA Water Quality Portal (WQP), aggregating monitoring records from federal, state, and tribal sources. Each measurement represents a single sample analyzed for a specific characteristic (e.g., E. coli, pH, dissolved oxygen, nitrogen).

Live USGS Streamgage

River & Stream Conditions

Current Discharge

12.2cfs

May 14, 7:05 PM UTC

vs Long-Term Average

69%

Below typical

Primary Streamgage

Waikolu Str blw pipe nr Kalaupapa, Molokai, HI

USGS site
16408000
Drainage area
3.78 sq mi
Long-term mean
17.7 cfs

One representative streamgage (the one with the largest drainage area in the county). Many counties have multiple gauges; this view summarizes the primary one. The long-term mean is the full-record annual average; the percent-of-typical value compares the latest reading against that average.

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Water Cost Estimate

3

3 people  ·  ~225 gal/day

Annual Total

$558

Monthly

$47

Water Bill

$558/yr

Filter Cost

$0/yr

Safety Grade for Kalawao County:F — Failing

High violation count or severe watershed conditions.

Estimates use the national average residential water rate ($0.0068/gal, EPA/AWWA 2023) and EPA WaterSense per-person consumption baseline (75 gal/person/day). Actual bills vary by utility, usage tier, and local infrastructure fees. For informational purposes only.

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Kalawao County has good water quality

Learn about water restrictions and conservation in your area.

Water Restrictions →

Frequently Asked Questions

What is the water quality in Kalawao County, Hawaii?
Kalawao County, Hawaii has a drinking-water quality grade of N/A with a score of N/A/100, based on EPA SDWIS compliance data. Compliance data is currently unavailable. Watershed health, monitoring records, and streamflow snapshots are reported separately on this page.
Are there any water violations in Kalawao County?
Violation data for Kalawao County is not currently available. Health-based violations indicate instances where contaminant levels exceeded EPA Maximum Contaminant Levels (MCLs).
How much water-quality monitoring happens in Kalawao County?
EPA's Water Quality Portal records 4,221 measurements from 80 monitoring sites in Kalawao County over the past five years. The most frequently measured characteristic groups are Physical, Nutrient, Biological, Algae, Phytoplankton. Each measurement is a single sample analyzed for one characteristic (E. coli, pH, dissolved oxygen, etc.). High monitoring density means more scientific evidence behind any reported signal — it does not by itself indicate water quality.
What's happening with rivers in Kalawao County right now?
Kalawao County's primary USGS streamgage on the Waikolu Str blw pipe has a pipeline snapshot of 12.2 cubic feet per second — 69% of the long-term mean of 17.73 cfs. Flow is within typical range for this gauge. For the latest gauge feed, visit waterdata.usgs.gov.
How does Kalawao County water compare to the Hawaii average?
Kalawao County's SDWIS water quality score of N/A/100 is not available for comparison. The average water quality grade across Hawaii is B, based on data from 4 counties with available SDWIS data.
Is tap water safe to drink in Kalawao County?
Based on EPA SDWIS data, Kalawao County has a water quality grade of N/A (N/A/100). Insufficient data is available to fully assess compliance. The grade speaks to the public water system, not the watershed — for watershed-level concerns, see the Watershed Health zone. For the most up-to-date information, contact your local water utility or review your Consumer Confidence Report (CCR).
Does Kalawao County have clean drinking water?
Kalawao County has no reported health-based drinking water violations according to EPA records. With a water quality score of N/A/100 and grade N/A, the county's drinking water has had some compliance issues but continues to be monitored. Note: drinking-water compliance speaks to the public water system, not necessarily to the watershed itself — check the Watershed Health zone for ATTAINS §303(d) data.
How is water quality measured?
WaterByCounty layers four federal datasets per county. The A–F drinking-water grade comes from EPA SDWIS (Safe Drinking Water Act compliance, 5-year violation lookback). The Watershed Health zone surfaces EPA ATTAINS §303(d) impairment data. The Monitoring zone summarizes EPA Water Quality Portal records. The Streamflow zone reports the latest USGS NWIS reading from the county's primary streamgage. Each is reported separately so you can see where the water is actually weakest.

Data Sources

Drinking-water compliance data from the EPA Safe Drinking Water Information System (SDWIS) via the ECHO enforcement database. Scores reflect compliance history and health-based violation counts.

Water-quality monitoring counts from the EPA Water Quality Portal (WQP), federated USGS, EPA, and state agency sampling records over a rolling 5-year window.

Live streamflow from the USGS National Water Information System (NWIS), continuous discharge measurements from the largest-drainage gauge in each county, compared against the full-record long-term annual mean.

Disclaimer: This data is informational only. It is not health, legal, or professional advice. For concerns about your specific water supply, contact your local water utility.

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

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