waterbycounty
Federal water data

County water report

Placer County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Placer County, California.

Water grade

A

Water score

69.8

State rank

#4

of 58

Health violations

4

EPA SDWIS, 5-year lookback

Watershed impaired

41.8%

91 water bodies assessed

Monitoring sites

41

13,016 recent measurements

Live streamflow

168%

TRUCKEE R NR TRUCKEE CA

Water at a glance

Key Water Indicators for Placer County

EPA SDWIS

Safety Grade

A

Score: 69.8 / 100

EPA SDWIS

Active Violations

4

5-year health-based lookback

EPA ATTAINS

Watershed Health

42% impaired

91 bodies assessed

USGS NWIS

Streamflow Snapshot

168% of mean

TRUCKEE R NR TRUCKEE CA

EPA WQP

Monitoring Sites

41

13,016 recent readings

Source: EPA SDWIS · Safe Drinking Water Information System

Drinking Water Compliance

Compliance grade

A

Based on EPA SDWIS compliance history.

Water score

Higher scores indicate cleaner recent compliance records.

69.8/100

Health violations

4

Health-based violations

Violations per 100K served

1.0

Population-normalized SDWIS rate

Editorial analysis

Understanding Placer County’s Water

Drinking Water Quality Overview

EPA SDWIS

Placer County earns an A grade for drinking water quality, scoring 69.8 out of 100. Over the past five years, EPA SDWIS records 4 health-based violations — a pattern that public water utilities are required to disclose and correct.

Watershed Conditions

EPA ATTAINS

Under the Clean Water Act §303(d), EPA ATTAINS tracks whether waterways meet quality standards for drinking, recreation, and aquatic life (reporting cycle: 2022). A substantial 41.8% of assessed waterways are impaired (38 of 91 water bodies) across Placer County's watersheds. The leading impairment causes are toxicity and mercury. Impairment does not mean tap water is unsafe — it measures ambient waterway conditions upstream of treatment, not finished drinking water.

River & Streamflow Status

USGS NWIS

USGS NWIS gauge data (as of 2026-05-14T11:45:00.000-07:00) puts TRUCKEE R at 498.0 cfs — running significantly above its long-term average at 168% of mean flow. 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. Placer County has moderate coverage with 41 active monitoring sites with 13,016 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 Placer County

Water Verdict

Placer County receives a fair water quality assessment with a grade of A and a score of 69.8 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

Placer County has recorded 4 health-based violations, indicating multiple instances where federal contaminant limits or treatment requirements were not met. At 1.0 violations per 100,000 people served, this rate is relatively low compared to many U.S. counties.

Consumer Guidance

Tap water compliance data for Placer County shows a A grade. Placer County's drinking-water compliance score is 69.8 out of 100. Reviewing your utility's most recent Consumer Confidence Report provides the most accurate picture of detected contaminants and treatment status. An NSF-certified water filter can add an extra layer of safety for any household concerns. Toxicity is the leading impairment cause in Placer County's watershed. A pipeline streamflow snapshot from the TRUCKEE R gauge is also available on this page.

Regional Context

Placer County has better water quality than the average county in California. Its water score is 25.2 points higher than the state average, indicating stronger water system performance relative to neighboring counties.

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

Contaminants & Resources

Key issues flagged in Placer County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    Toxicity

    Impairment cause per EPA Clean Water Act §303(d) assessment

  • 2

    Mercury

    Impairment cause per EPA Clean Water Act §303(d) assessment

  • 3

    Cypermethrin

    Impairment cause per EPA Clean Water Act §303(d) assessment

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for Placer County

EPA How's My Waterway

Interactive watershed health data for Placer County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Placer County

Consumer Confidence Reports (CA)

Annual water quality reports from utilities in California

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

41.8%

38 of 91 assessed

Moderate concern

Top Impairment Causes

  • 1

    TOXICITY

  • 2

    MERCURY

  • 3

    CYPERMETHRIN

Source: EPA ATTAINS · Reporting cycle 2022

Impairment is determined under the Clean Water Act §303(d): a water body is impaired when it fails to meet state-defined quality standards for designated uses (drinking, recreation, aquatic life). Assessment coverage varies by state; counties without assessed water bodies are not shown.

Past 5 years

Water Quality Monitoring

Monitoring Sites

41

Active in the past 5 years

Measurements Recorded

13K

13,016 total readings

Most Measured

  • Physical
  • Nutrient
  • Organics, Other

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

498cfs

May 14, 6:45 PM UTC

vs Long-Term Average

168%

Well above typical

Primary Streamgage

TRUCKEE R NR TRUCKEE CA

USGS site
10338000
Drainage area
553 sq mi
Long-term mean
297 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 Placer County:C — Moderate

Some violations or watershed impairment detected.

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.

Try the full calculator →

Improve your water quality at home

Berkey filters remove 99.9%+ of contaminants from tap water.

Shop Berkey →

Sponsored

Test your tap water

Tap Score provides professional mail-in water testing.

Get Tested →

Frequently Asked Questions

What is the water quality in Placer County, California?
Placer County, California has a drinking-water quality grade of A with a score of 69.8/100, based on EPA SDWIS compliance data. The county has 4 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 Placer County?
Placer County has 4 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 healthy are the watersheds in Placer County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 41.8% of Placer County's 91 assessed water bodies are classified as impaired (38 impaired). The top reported causes are TOXICITY, MERCURY, CYPERMETHRIN. Impairment means the water body fails to meet state quality standards for at least one designated use — drinking water source, recreation, aquatic life, or fish consumption. Note: watershed impairment doesn't always translate to tap-water issues; treatment plants can remove most regulated contaminants.
How much water-quality monitoring happens in Placer County?
EPA's Water Quality Portal records 13,016 measurements from 41 monitoring sites in Placer County over the past five years. The most frequently measured characteristic groups are Physical, Nutrient, Organics, Other. 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 Placer County right now?
Placer County's primary USGS streamgage on the TRUCKEE R has a pipeline snapshot of 498 cubic feet per second — 168% of the long-term mean of 296.67 cfs. This is well above typical — often a signal of recent precipitation or storm runoff. For the latest gauge feed, visit waterdata.usgs.gov.
How does Placer County water compare to the California average?
Placer County's SDWIS water quality score of 69.8/100 is higher than the California state average of 44.6. The average water quality grade across California is D, based on data from 58 counties with available SDWIS data.
Is tap water safe to drink in Placer County?
Based on EPA SDWIS data, Placer County has a water quality grade of A (69.8/100). This indicates good to excellent water quality with strong SDWIS 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 Placer County have clean drinking water?
Placer County has 4 health-based drinking water violations according to EPA records. With a water quality score of 69.8/100 and grade 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 does Placer County rank for water quality in California?
Placer County ranks #4 out of 58 counties in California by SDWIS water quality score (1 = best). With a score of 69.8/100, it falls in the top 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.

Counties with Similar Water Quality

Sacramento County

California

B

69.0

Water score

Orange County

California

A

71.5

Water score

Alameda County

California

A

71.9

Water score

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.

Watershed health and impaired-waterway data from the EPA ATTAINS Clean Water Act §303(d) assessments, state-reported and EPA-finalized.

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

Explore more data for Placer County

Property TaxCost of LivingCrime RateIncomeHealthSchoolsDisaster RiskWeatherCounty Score