Indiana lake · state assessment record
Monroe Reservoir (Lower) (Pws)
Assessment decisions reported by Indiana to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2005 reporting cycle.
- 6,863
- Assessed acres
- Lake, Freshwater
- Water type
This waterbody in one line
Monroe Reservoir (Lower) (Pws), 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 (2005). By assessed acreage it sits among the largest 1% of assessed lakes nationally (38,628 lakes with a filed area); its impairment list is among the longest nationally (2 listed causes vs 23,610 assessed lakes). Indiana assesses human health and wildlife as supported; it reported no verdict on fish consumption itself.
- Not Supporting
- overall status
- P99
- Assessed size nationally
- P10
- 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.
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.
How Monroe Reservoir (Lower) (Pws) reads against 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 Monroe Reservoir (Lower) (Pws) nationally is assessed size: 6,863 acres, larger than 99% of the 38,628 lake-type units with an area on file.
Monroe Reservoir (Lower) (Pws): Category 5, TMDL still owed
Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Monroe Reservoir (Lower) (Pws). Read the listed causes and any cleanup actions filed beside them before treating the overall status tile as a finished restoration story.
Every ruled-on use is fully supporting
The filed use determinations for fish consumption 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.
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 Monroe Reservoir (Lower) (Pws) 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 Monroe Reservoir (Lower) (Pws) without modification. See our methodology for reporting-unit limits and gauge linking rules.
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.
| Designated use | Group | Verdict |
|---|---|---|
| Human Health and Wildlife | Fish-consumption or fishery | Fully Supporting |
| Public Water Supply | Drinking-water supply designation | Not Supporting |
| Full Body Contact | Recreation | Not Assessed |
| 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 |
|---|---|---|---|
| Taste | Public Water Supply | 1998 | TMDL priority: Medium |
| Algae | Public Water Supply | 2018 | TMDL priority: Medium |
Probable sources named by the state
Each source below is listed under the cause the state filed it against, and carries the word the state filed with it — confirmed, or suspected.
- Taste
- Non-Point Source (suspected)
Reading the record
Where Monroe Reservoir (Lower) (Pws) sits among peers
55% of Indiana's lakes assessed this deeply also came out mixed
Indiana ruled definitively on 2 designated uses at Monroe Reservoir (Lower) (Pws) and found 1 of 2 not 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.
Computed share from EPA ATTAINS filed records, not an official EPA rating or safety grade.
| 1 | 2 | 3 | 4 | 5+ | |
|---|---|---|---|---|---|
| All supported | 79 | 16 | 1 | 0 | 0 |
| Mixed | Not possible | 38 (this record) | 12 | 5 | 0 |
| None supported | 72 | 15 | 3 | 0 | 0 |
Ringed cell: Monroe Reservoir (Lower) (Pws). Source: EPA ATTAINS, Reporting cycles 1987–2026.
Scale and rank
Monroe Reservoir (Lower) (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 6,863 assessed acres it ranks 466th 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 465 lakes with a larger one.
Awaiting a filing
The state has not yet filed a definitive recreation verdict and a definitive aquatic-life verdict for this record; those fields populate when it reports them in a future Integrated Report cycle.
In context
Where Monroe Reservoir (Lower) (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
6,863 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
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 Monroe Reservoir (Lower) (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, Monroe Reservoir (Lower) (Pws) ranks 9th by listed-cause count (2 listed causes) and 3rd by assessed size among the 156 with an area filed; it sits in the not-supporting set (145 statewide) . Its listed causes (Taste and Algae) sit outside Indiana's top-five list, which is 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 |
| 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 Monroe Reservoir (Lower) (Pws)'s size or cause load
Similar assessed acres
Nearest filed extents (6,863 acres here).
- Toledo Bend Reservoir · 6,873 acres · TX
- Columbia River · 6,874 acres · OR
- Columbia River · 6,875 acres · OR
- Fletcher Pond · 6,814 acres · MI
Similar cause load
Nearest listed-cause counts (2 here). Peers already in the acreage column are omitted.
- 12th St. Beach · 2 causes · IL
- 31st St. Beach · 2 causes · IL
- 49th St. Beach · 2 causes · IL
- 57th St. Beach · 2 causes · IL
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 INW08P1024_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.