Indiana lake · state assessment record

Patoka Reservoir (Pws)

Assessment decisions reported by Indiana to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2004 reporting cycle.

8,880
Assessed acres
Lake, Freshwater
Water type
View watchlist

This waterbody in one line

Patoka Reservoir (Pws), a lake in Indiana, is assessed as fully supporting its designated uses, with no impairment causes listed in the state's most recent Integrated Report cycle (2004). By assessed acreage it sits among the largest 1% of assessed lakes nationally (38,628 lakes with a filed area); its impairment list is shorter than on half of assessed lakes (0 listed causes). Indiana assesses human health and wildlife as supported; it reported no verdict on fish consumption itself.

Fully Supporting
overall status
P99
Assessed size nationally
P51
Shorter cause list
Fully Supporting
fish-consumption or fishery

Assessment verdicts are the state agency's decisions as reported to EPA ATTAINS; PlainLakes renders them without modification.

B+
Water Quality Standing
77/100
Patoka Reservoir (Pws)

A composite of this record's EPA ATTAINS designated-use verdicts, filed impairment count, and assessment currency, weighted and benchmarked against the national corpus of assessed active waterbodies. This is a water-quality standing, not a human-recreation or property-value judgment, and dimensions with no filed verdict drop out rather than count against the score.

RecreationA+
Meeting criteria
Swimming, boating, and other primary/secondary contact recreation
Drinking WaterN/A
Not assessed
Suitability as a public drinking-water source
Aquatic LifeN/A
Not assessed
Support for fish, invertebrates, and other aquatic organisms
Fish ConsumptionA+
Meeting criteria
Safety of eating fish caught in this water
Impairment BurdenA+
0 causes
Filed pollutant/stressor causes on this record
Assessment CurrencyF
2004
Reporting cycle this record’s verdicts were last decided in

Reading Patoka Reservoir (Pws)'s filed record

Paragraphs are selected by this unit's percentiles and use matrix: different lakes lead with different dimensions. Figures are ATTAINS / portal register arithmetic, not advice.

The signature stat: cause-list length

The standout filed fact is a short cause list: 0 causes, shorter than 51% of assessed lake-type units. A short list can mean a focused impairment, or a shallow assessment.

Large assessed unit

At 8,880 acres, Patoka Reservoir (Pws) clears the upper tercile of assessed lake-type units with an area on file (362 still larger). Size comparisons use the portal's deduplicated lake ranking population, not raw ATTAINS row counts.

Every filed use clears the bar

The filed use determinations for fish consumption, recreation are all Fully Supporting. Where an overall IR category still flags the unit, look at the cause list and report standing rather than treating the use row as empty.

Large within Indiana

Among Indiana's 156 indexed units with an area, Patoka Reservoir (Pws) ranks 2 by assessed size, toward the large end of that state file.

IR category in the supporting band

EPA's Integrated Report category for Patoka Reservoir (Pws) is 2. In ATTAINS that band means the assessed uses are supporting (or supporting with other waters in the unit), so the narrative weight shifts to how deep the assessment went and whether monitoring is current, not to a restoration plan.

According to the U.S. Environmental Protection Agency's ATTAINS program, Indiana carries 1,588 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Patoka Reservoir (Pws) without modification. See our methodology for reporting-unit limits and gauge linking rules.

Reporting cycle
2004
Indiana Integrated Report
Listing category
Category 2
Uses with verdicts
2
Definitive use assessments
Sources retrieved
2026-08-17
Portal-wide ATTAINS + NWIS pull

The record

Designated-use assessments

Fully Supporting and Not Supporting are the state's definitive verdicts; other entries mean the use was not conclusively assessed in this cycle. Indiana filed its own confidence on the one definitive verdict it rated: Excellent. That rating is the filer's, in EPA's own field, and EPA publishes no definition of the four words it offers.

Designated use Group Verdict
Full Body Contact Recreation Fully Supporting
Human Health and Wildlife Fish-consumption or fishery Fully Supporting
Filer confidence: Excellent
Public Water Supply Drinking-water supply designation Not Assessed
Warm Water Aquatic Life Aquatic-life or related Not Assessed

The record

Listed impairment causes

The state's reported assessment lists no impairment causes for this lake.

Reading the record

Patoka Reservoir (Pws): Category 2 reading

2 Category 2: some uses supported, others not assessed

Indiana filed this assessment unit as Category 2: some designated uses are supported and others were not assessed in this cycle. Absence of a failing verdict is not the same as a full Category 1 finding.

How these categories work.

Scale and rank

Patoka Reservoir (Pws) is one of 1,588 lake-type waterbodies reported to EPA from Indiana, and one of 162 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 8,880 assessed acres it ranks 363rd by assessed size among the 38,628 lakes the dataset carries an area for, counting a state’s repeated filings of one water once, behind 362 lakes with a larger one.

What this record holds

Indiana completed an assessment here and listed no impairment cause, so the record holds a verdict and its supporting use rows but no pollutant to track over time. The state has not yet filed a definitive aquatic-life verdict for this record; that field populates when it reports it in a future Integrated Report cycle.

In context

Where Patoka Reservoir (Pws) sits nationally

Assessed size among U.S. lakes

Distribution of assessed acreage across ATTAINS lakes filed with an area, counting a state’s repeated filings of one water once

8,880 Top 1% larger than 99% of 38,628 lakes

lakes the dataset carries an area for, counting a state’s repeated filings of one water once, bucketed by value

Source EPA ATTAINS · Reporting cycles 1987–2026

Listed causes vs waterbodies carrying a verdict

How many impairment causes U.S. waterbodies with a reported verdict carry

0 Among the shortest cause lists fewer listed causes than 51% of 23,610 waterbodies carrying a verdict

named waterbodies carrying a verdict, bucketed by value

Source EPA ATTAINS · Reporting cycles 1987–2026

In both charts each bar is a band and taller bars hold more waterbodies; the dashed line and filled bar mark Patoka Reservoir (Pws). Hover or tap any bar for its full count and share.

In context

Indiana context

ATTAINS carries 1,588 lake-type waterbodies in Indiana, 145 assessed as not supporting at least one use and 96 fully supporting. Among the 162 indexed units there, Patoka Reservoir (Pws) ranks 145th by listed-cause count (no listed causes) and 2nd by assessed size among the 156 with an area filed; it is one of the 96 fully-supporting indexed records in the state .

Other large assessed lakes in Indiana Assessed acres
Lake Michigan (Not Indexed) (Salmonid) (Osrw) Not Supporting 154,176
Monroe Reservoir (Lower) (Pws) Not Supporting 6,863
Brookville Reservoir Not Supporting 5,260
Monroe Reservoir (Upper) (Pws) Not Supporting 3,887
Wawasee, Lake Not Supporting 3,410
Gibson Generating Plant Lake Not Assessed 3,200

Peers near Patoka Reservoir (Pws)'s size or cause load

Similar assessed acres

Nearest filed extents (8,880 acres here).

Similar cause load

Nearest listed-cause counts (0 here). Peers already in the acreage column are omitted.

How peers are picked

What to do with this record

  • Assessment verdicts are cycle-based, not real-time. For fish-consumption decisions, your state advisory program is the binding source. Consumption status guide
  • Impairment listings follow the Clean Water Act 303(d) process; a listing is a regulatory finding, not a closure notice. 303(d) explained

PlainLakes renders state assessment decisions and federal gauge observations without modification. It does not issue advisories.

Assessment decisions on this page are rendered directly from state Integrated Report records in EPA's ATTAINS system; gauge figures are daily-value observations from the USGS National Water Information System, no number is typed in by an editor. Overall status, use verdicts, and causes are the state's reported decisions for assessment unit INP09P1001_00. Counts and percentiles are computed across all lake-type records PlainLakes ingests from ATTAINS. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-08-17. Primary sources: EPA ATTAINS and USGS National Water Information System.