Indiana lake · state assessment record

Hamilton Lake

Assessment decisions reported by Indiana to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2008 reporting cycle.

802
Assessed acres
Lake, Freshwater
Water type
8.5 ft
Gage Height (provisional)
View watchlist

This waterbody in one line

Hamilton Lake, a lake in Indiana, is assessed as not supporting one or more designated uses, with 2 listed impairment causes in the state's most recent Integrated Report cycle (2008). By assessed acreage it sits among the largest 10% by assessed acreage nationally (38,628 lakes); its impairment list is among the longest nationally (2 listed causes vs 23,610 assessed lakes). Indiana assesses human health and wildlife as not supported; it reported no verdict on fish consumption itself. A USGS gauge tracks its gage height daily.

Not Supporting
overall status
P93
Assessed size nationally
P10
Shorter cause list
Not Supporting
fish-consumption or fishery

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

F
Water Quality Standing
6/100
Hamilton Lake

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.

RecreationF
Not supporting
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 ConsumptionF
Not supporting
Safety of eating fish caught in this water
Impairment BurdenF
2 causes
Filed pollutant/stressor causes, vs. the national corpus of assessed active units
Assessment CurrencyF
2008
Reporting cycle this record’s verdicts were last decided in

Where Hamilton Lake stands in the filed register

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: assessed size

The number that most separates Hamilton Lake nationally is assessed size: 802 acres, larger than 93% of the 38,628 lake-type units with an area on file.

No ruled-on use clears the bar

On the uses this filer ruled on, fish consumption, recreation, every determination is Not Supporting. That is a use-by-use reading of the filed record, not a single overall lake grade.

Hamilton Lake: Category 5, TMDL still owed

Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Hamilton Lake. Read the listed causes and any cleanup actions filed beside them before treating the overall status tile as a finished restoration story.

Longer than most cause lists

2 listed causes puts this unit above 80% of assessed lake-type records by list length. Treat that as a coding-and-sampling signal: states that split pollutants finely mint longer lists without proving worse water.

Overall status: not supporting

The filer's overall status for Hamilton Lake is Not Supporting. That tile summarizes the assessment unit; the designated-use rows and cause list are the evidence behind it.

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 Hamilton Lake without modification. See our methodology for reporting-unit limits and gauge linking rules.

Reporting cycle
2008
Indiana Integrated Report
Listing category
Category 5
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 Not Supporting
Filer confidence: Excellent
Human Health and Wildlife Fish-consumption or fishery Not Supporting
Warm Water Aquatic Life Aquatic-life or related Not Assessed

The record

Listed impairment causes

Causes the state listed as impairing designated uses of this lake, with the cycle each was first listed and the Clean Water Act action recorded against it.

Cause Affected uses First listed Cleanup standing
PCBs in Fish Tissue Human Health and Wildlife 2006 TMDL priority: Low
Phosphorus, Total Full Body Contact 2006 TMDL priority: Medium

Probable sources

Indiana listed the source of the impairment as unknown. That is the state's own filed value, not a gap in this record: the cause has been identified, the origin has not.

Reading the record

Where Hamilton Lake sits among peers

22% of Indiana's lakes assessed this deeply also had no use supported

Indiana ruled definitively on 2 designated uses at Hamilton Lake and found none of them supported. The dataset shows 69 Indiana lakes judged to that same depth.

Indiana's assessed lakes are most often judged on 1 use; this one was judged on 2.

22 N

Computed share from EPA ATTAINS filed records, not an official EPA rating or safety grade.

Share of Indiana lakes judged on 2 designated uses with the same outcome
Assessed lakes in Indiana by how many uses were ruled on and how those rulings came out
Less More
Assessed lakes in Indiana by how many uses were ruled on and how those rulings came out (lakes)
12345+
All supported 7916100
Mixed Not possible381250
None supported 7215 (this record)300

Ringed cell: Hamilton Lake. Source: EPA ATTAINS, Reporting cycles 1987–2026.

Scale and rank

Hamilton Lake 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 802 assessed acres it ranks 2,646th 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 2,645 lakes with a larger one.

Water level

A USGS gauge tracks this lake's gage height daily, and the latest reading is 0.05 ft above the reading 30 days earlier, against a 365-day observed range of 1.4 ft. 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.

Water level: 365-day record

Daily gage height values, feet above this gauge’s own local zero, not above sea level, from USGS gauge 04177700 (Hamilton Lake at Hamilton, in), shown weekly. Readings are daily-batch snapshots, not real-time conditions. Each daily value is a single reading taken at 24:00, not a daily mean. It is the only daily statistic USGS files for this gauge.

1.4 ft annual swing
Latest reading
8.5 ft 0.049999999999998934ft vs 30 days earlier
2026-08-15 · Provisional, subject to USGS revision
Latest reading
8.5 ft
2026-08-15 · Provisional, subject to USGS revision
365-day range
1.4 ft
8.3 to 9.6
30-day change
+0.05 ft
vs 30 days earlier
Observations
300
reading at 24:00 values, 365 days
88.599.5 08-1609-2711-0801-1304-0605-1806-2908-1008-15 8.53

Source: USGS National Water Information System As of Trailing 365 days, through 2026-08-16

Water level: 365-day record

Subscribe to water level updates for Hamilton Lake (RSS)

171 of the 300 daily values in this window (57%) are provisional and subject to USGS revision; USGS has approved this gauge's record through 2026-02-19.

Full gauge record: USGS monitoring location 04177700

In context

Where Hamilton Lake 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

802 Top 7% larger than 93% 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

2 Longer than most more listed causes than 80% 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 Hamilton Lake. 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, Hamilton Lake ranks 14th by listed-cause count (2 listed causes) and 21st by assessed size among the 156 with an area filed; it sits in the not-supporting set (145 statewide) . Its listed causes include PCBs in Fish Tissue; and Phosphorus, Total, which also appear among Indiana's most-filed impairment causes (led by PCBs in Fish Tissue).

Other large assessed lakes in Indiana Assessed acres
Lake Michigan (Not Indexed) (Salmonid) (Osrw) Not Supporting 154,176
Patoka Reservoir (Pws) Fully Supporting 8,880
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

Peers near Hamilton Lake's size or cause load

Similar assessed acres

Nearest filed extents (802 acres here).

Similar cause load

Nearest listed-cause counts (2 here). Peers already in the acreage column are omitted.

How peers are picked

What to do with this record

  • The listing here is on a fishery use, not on fish consumption, and this state reported no consumption verdict for this lake. Your state fish-advisory program is the source for whether the catch is safe to eat. Consumption status guide
  • Water levels shown are daily snapshots. Seasonal drawdown and datum conventions matter when comparing levels. How to read level data
  • 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 INA03P1011_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.