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County water report

Hernando County Water Report

Drinking-water compliance, watershed health, monitoring records, and river conditions for Hernando County, Florida.

Water grade

A

Water score

70.8

State rank

#15

of 66

Health violations

1

EPA SDWIS, 5-year lookback

Watershed impaired

50.2%

823 water bodies assessed

Monitoring sites

202

45,494 recent measurements

Live streamflow

2%

WITHLACOOCHEE RIVER AT NOBLETON, FL

Water at a glance

Key Water Indicators for Hernando County

EPA SDWIS

Safety Grade

A

Score: 70.8 / 100

EPA SDWIS

Active Violations

1

5-year health-based lookback

EPA ATTAINS

Watershed Health

50% impaired

823 bodies assessed

USGS NWIS

Streamflow Snapshot

2% of mean

WITHLACOOCHEE RIVER AT NOBLETON, FL

EPA WQP

Monitoring Sites

202

45,494 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.

70.8/100

Health violations

1

Health-based violations

Violations per 100K served

0.6

Population-normalized SDWIS rate

Editorial analysis

Understanding Hernando County’s Water

Drinking Water Quality Overview

EPA SDWIS

Hernando County earns an A grade for drinking water quality, scoring 70.8 out of 100. Over the past five years, EPA SDWIS records 1 health-based violation — a single incident worth monitoring.

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 50.2% of assessed waterways are impaired (413 of 823 water bodies) across Hernando County's watersheds. The leading impairment causes are mercury in fish tissue and dissolved oxygen. 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 2026-05-14T14:30:00.000-04:00) puts WITHLACOOCHEE RIVER at 4.9 cfs — well below its long-term average at 2% of mean — low-flow conditions worth noting for water-dependent ecosystems. 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. Hernando County has extensive coverage with 202 active monitoring sites with 45,494 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 Hernando County

Water Verdict

Hernando County, Florida receives a good water quality assessment with a grade of A and a score of 70.8 out of 100. While the water supply is generally safe, occasional monitoring gaps or minor contaminant detections may occur. Separately, EPA ATTAINS assessments cover 823 water bodies in the county's watershed, with 50.2% listed as impaired under the Clean Water Act — a source-water measure that is tracked independently of tap-water compliance. At the most recent USGS reading, local streamflow was below its historical mean at 1.6% — worth watching in drier seasons.

Violation Context

EPA SDWIS records for Hernando County, Florida show 1 health-based violation, meaning a water system experienced at least one exceedance of federal contaminant limits or treatment requirements. At 0.6 violations per 100,000 people served, this rate is relatively low compared to many U.S. counties. This compliance record sits alongside an unusually deep monitoring archive: 45,494 water-quality results have been logged across the county in the EPA Water Quality Portal over the past five years.

Consumer Guidance

Tap water in Hernando County earns a Grade A overall with a small number of isolated health violations in the recent record. Hernando County's drinking-water compliance score is 70.8 out of 100. The violation rate for Hernando County is 0.6 per 100,000 people served. These violations were likely resolved quickly; Grade A reflects a strong multi-year compliance trend. Reviewing the most recent Consumer Confidence Report will show exactly which systems were affected and what corrective action was taken. With 202 active water-quality monitoring sites in Hernando County, data coverage is strong. Mercury in Fish Tissue is the leading impairment cause in Hernando County's watershed. A pipeline streamflow snapshot from the WITHLACOOCHEE RIVER gauge is also available on this page.

Regional Context

Hernando County has better water quality than the average county in Florida. Its water score is 14.8 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 Hernando County's water environment

Watershed Impairment Causes (EPA ATTAINS)

  • 1

    Mercury (fish tissue)

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

  • 2

    Low dissolved oxygen

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

  • 3

    Chlorophyll-a (algae indicator)

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

Source: EPA ATTAINS · Reporting cycle 2022

Official EPA Resources for Hernando County

EPA How's My Waterway

Interactive watershed health data for Hernando County

EPA ECHO: Drinking Water Systems

Search water utilities and violation records for Hernando County

Consumer Confidence Reports (FL)

Annual water quality reports from utilities in Florida

Clean Water Act §303(d)

Watershed Health

Impaired Water Bodies

50.2%

413 of 823 assessed

Moderate concern

Top Impairment Causes

  • 1

    MERCURY IN FISH TISSUE

  • 2

    DISSOLVED OXYGEN

  • 3

    CHLOROPHYLL-A

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

202

Active in the past 5 years

Measurements Recorded

45K

45,494 total readings

Most Measured

  • Physical
  • Nutrient
  • Inorganics, Minor, Metals

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

4.93cfs

May 14, 6:30 PM UTC

vs Long-Term Average

2%

Well below typical

Primary Streamgage

WITHLACOOCHEE RIVER AT NOBLETON, FL

USGS site
02312558
Drainage area
816 sq mi
Long-term mean
311 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 Hernando 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.

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Frequently Asked Questions

What is the water quality in Hernando County, Florida?
Hernando County, Florida has a drinking-water quality grade of A with a score of 70.8/100, based on EPA SDWIS compliance data. The county has 1 health-based drinking water violation over the past 5 years. Watershed health, monitoring records, and streamflow snapshots are reported separately on this page.
Are there any water violations in Hernando County?
Hernando County has 1 health-based drinking water violation 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 Hernando County?
EPA ATTAINS assessments under Clean Water Act §303(d) indicate 50.2% of Hernando County's 823 assessed water bodies are classified as impaired (413 impaired). The top reported causes are MERCURY IN FISH TISSUE, DISSOLVED OXYGEN, CHLOROPHYLL-A. 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 Hernando County?
EPA's Water Quality Portal records 45,494 measurements from 202 monitoring sites in Hernando County over the past five years. The most frequently measured characteristic groups are Physical, Nutrient, Inorganics, Minor, Metals. 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 Hernando County right now?
Hernando County's primary USGS streamgage on the WITHLACOOCHEE RIVER has a pipeline snapshot of 4.93 cubic feet per second — 2% of the long-term mean of 311.12 cfs. This is well below typical — often a signal of drought stress on source water. For the latest gauge feed, visit waterdata.usgs.gov.
How does Hernando County water compare to the Florida average?
Hernando County's SDWIS water quality score of 70.8/100 is higher than the Florida state average of 56.0. The average water quality grade across Florida is D, based on data from 66 counties with available SDWIS data.
Is tap water safe to drink in Hernando County?
Based on EPA SDWIS data, Hernando County has a water quality grade of A (70.8/100). 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 Hernando County have clean drinking water?
Hernando County has 1 health-based drinking water violation according to EPA records. With a water quality score of 70.8/100 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 Hernando County rank for water quality in Florida?
Hernando County ranks #15 out of 66 counties in Florida by SDWIS water quality score (1 = best). With a score of 70.8/100, 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

Broward County

Florida

A

70.6

Water score

Manatee County

Florida

A

70.6

Water score

Clay County

Florida

A

71.1

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

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