waterbycounty

County water report

Pierce County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Pierce County, Washington.

Water grade

C

Water score

57.1

State rank

#24

of 39

Health violations

95

EPA SDWIS, 5-year lookback

Watershed impaired

Not reported

EPA ATTAINS coverage varies by state

Monitoring sites

145

76,507 recent measurements

Live streamflow

111%

PUYALLUP RIVER AT PUYALLUP, WA

Water at a glance

Key Water Indicators for Pierce County

EPA SDWIS

Safety Grade

C

Score: 57.1 / 100

EPA SDWIS

Active Violations

95

5-year health-based lookback

EPA ATTAINS

Watershed Health

Not reported

Coverage varies by state

USGS NWIS

Streamflow Snapshot

111% of mean

PUYALLUP RIVER AT PUYALLUP, WA

EPA WQP

Monitoring Sites

145

76,507 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

C

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

57.1/100

Health violations

95

Health-based violations

Violations per 100K served

8.8

Population-normalized SDWIS rate

Data center water stress

Pierce County has 3 facilities in the DCWSI dataset.

ByCounty's DCWSI ranks this county #132 nationally by combining its water score with mapped data center density.

DCWSIThe Data Center Water Stress Index: 60% the county's water-system stress plus 40% how concentrated data centers already are, scored 0-100. Higher means data-center density and water pressure overlap more here.

58.7

0-100 index

Facility count

3

61.1 density percentile

Discharge estimate

Not reported

EPA CWA fields where available

Water vs median

+7.1

Compared with US county median

Mapped facilities

  • Centeris

    Facility details limited

    OSM
  • Centeris SH1 Colocation

    Puyallup

    OSM
  • Centeris SH2 Build-to-Suit

    Puyallup

    OSM

Data Center Water Budget Calculator

Estimate daily water use for a hypothetical facility in Pierce County.

1 MW1,000 MW
40%100%
799K gallons/dayHigh Impact

Your facility would use 27.5% of this county's industrial water baseline. Verify water rights and long-term drought projections before committing.

27.5% of county industrial baseline2.10 Mgal/day remaining headroom

Based on USGS 2020 water-use data and EPA-standard cooling intensity constants. Not a substitute for site-specific water rights analysis.

Editorial analysis

Understanding Pierce County’s Water

Drinking Water Quality Overview

EPA SDWIS

Pierce County's drinking water earned a C grade, scoring 57.1 out of 100. Over the past five years, EPA SDWIS records 95 health-based violations — a pattern that public water utilities are required to disclose and correct.

River & Streamflow Status

USGS NWIS

USGS NWIS gauge data (as of 2026-05-14T11:45:00.000-07:00) puts PUYALLUP RIVER at 3.7k cfs — flowing above its historical average at 111% 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. Pierce County has extensive coverage with 145 active monitoring sites with 76,507 recent measurements on record. Predominant monitoring categories include physical and microbiological. 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 Pierce County

Water Verdict

Pierce County receives a fair water quality assessment with a grade of C and a score of 57.1 out of 100. The water supply meets baseline federal standards, but there may be periods of elevated contaminant levels or infrastructure concerns worth monitoring.

Violation Context

Pierce County has recorded 95 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 8.8 violations per 100,000 people served, this rate is high and signals significant water quality management issues.

Consumer Guidance

Tap water in Pierce County meets baseline standards but the compliance record shows room for improvement, with a Grade C rating. Pierce County's drinking-water compliance score is 57.1 out of 100. The violation rate for Pierce County is 8.8 per 100,000 people served. Residents who are immunocompromised, pregnant, or have young children may benefit from using an NSF 53-certified filter. Contacting your local utility for the current Consumer Confidence Report will confirm which specific violations were recorded and whether they have been resolved. With 145 active water-quality monitoring sites in Pierce County, data coverage is strong. A pipeline streamflow snapshot from the PUYALLUP RIVER gauge is also available on this page.

Regional Context

Pierce County has water quality close to the average county in Washington. Its water score is within 2.2 points of the state average, meaning its overall water system performance is broadly representative of Washington as a whole.

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

145

Active in the past 5 years

Measurements Recorded

77K

76,507 total readings

Most Measured

  • Physical
  • Microbiological
  • Nutrient

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

3,690cfs

May 14, 6:45 PM UTC

vs Long-Term Average

111%

Above typical

Primary Streamgage

PUYALLUP RIVER AT PUYALLUP, WA

USGS site
12101500
Drainage area
948 sq mi
Long-term mean
3,319 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.

Free tool

Estimate Your Water Costs

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 Pierce County:DPoor

Elevated violations or significant watershed impairment.

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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Frequently Asked Questions

What is the water quality in Pierce County, Washington?
Pierce County, Washington has a drinking-water quality grade of C with a score of 57.1/100, based on EPA SDWIS compliance data. The county has 95 health-based drinking water violations over the past 5 years. Watershed health, monitoring records, and streamflow snapshots are reported separately on this page.
Are there any water violations in Pierce County?
Pierce County has 95 health-based drinking water violations recorded by the EPA over the past 5 years. Health-based violations indicate instances where contaminant levels exceeded EPA Maximum Contaminant Levels (MCLs). Violations may have been resolved — check with your local water utility for current status.
How much water-quality monitoring happens in Pierce County?
EPA's Water Quality Portal records 76,507 measurements from 145 monitoring sites in Pierce County over the past five years. The most frequently measured characteristic groups are Physical, Microbiological, Nutrient. 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 Pierce County right now?
Pierce County's primary USGS streamgage on the PUYALLUP RIVER has a pipeline snapshot of 3,690 cubic feet per second — 111% of the long-term mean of 3,319.03 cfs. Flow is within typical range for this gauge. For the latest gauge feed, visit waterdata.usgs.gov.
How does Pierce County water compare to the Washington average?
Pierce County's SDWIS water quality score of 57.1/100 is lower than the Washington state average of 59.3. The average water quality grade across Washington is D, based on data from 39 counties with available SDWIS data.
Is tap water safe to drink in Pierce County?
Based on EPA SDWIS data, Pierce County has a water quality grade of C (57.1/100). This indicates moderate compliance. Some violations have been recorded but overall standards are maintained. 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).
Why does Pierce County have so many water violations?
Pierce County has 95 health-based drinking water violations on record from the EPA SDWIS database. A higher violation count can result from aging infrastructure, underfunded water utilities, agricultural runoff contamination, or industrial pollution. Counties with more water systems may also see more violations simply due to scale. Residents concerned about water quality should consider independent water testing and home filtration systems.
How does Pierce County rank for water quality in Washington?
Pierce County ranks #24 out of 39 counties in Washington by SDWIS water quality score (1 = best). With a score of 57.1/100, it falls in the middle third of counties statewide. The ranking reflects EPA SDWIS compliance only — not watershed impairment, monitoring density, or streamflow, which are tracked separately on this page.

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