Virginia reservoir · state assessment record
Lake Culpeper
Assessment decisions reported by Virginia to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2026 reporting cycle, a cycle that is open for public comment.
- 250
- Assessed acres
- Reservoir
- Water type
This waterbody in one line
Lake Culpeper, a reservoir in Virginia, is assessed as not supporting one or more designated uses, with 2 listed impairment causes in the state's most recent Integrated Report cycle (2026), a cycle that is open for public comment. By assessed acreage it sits in the upper quartile by assessed acreage nationally (38,628 lakes); its impairment list is among the longest nationally (2 listed causes vs 23,610 assessed lakes). Aquatic life is assessed as not supporting. Fish consumption is assessed as fully supporting.
- Not Supporting
- overall status
- P84
- Assessed size nationally
- P10
- Shorter cause list
- Not Supporting
- aquatic life
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 Lake Culpeper 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 Lake Culpeper nationally is assessed size: 249.7 acres, larger than 84% of the 38,628 lake-type units with an area on file.
Mixed use determinations
This record splits: Not Supporting on aquatic life, Fully Supporting on fish consumption. The divergence is inside the designated-use matrix, not a single all-or-nothing label.
Lake Culpeper: Category 5, TMDL still owed
Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Lake Culpeper. 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 Lake Culpeper 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, Virginia carries 275 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Lake Culpeper 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. Virginia filed its own confidence on the 4 definitive verdicts it rated: Good. 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 |
|---|---|---|
| Aquatic Life | Aquatic-life or related | Not Supporting Filer confidence: Good |
| Fish Consumption | Fish-consumption or fishery | Fully Supporting Filer confidence: Good |
| Public Water Supply | Drinking-water supply designation | Fully Supporting Filer confidence: Good |
| Wildlife | Other | Fully Supporting Filer confidence: Good |
| Recreation | Recreation | Insufficient Information Filer confidence: Good |
The record
Listed impairment causes
Causes the state listed as impairing designated uses of this reservoir, with the cycle each was first listed and the Clean Water Act action recorded against it.
| Cause | Affected uses | First listed | Cleanup standing |
|---|---|---|---|
| Dissolved Oxygen | Aquatic Life | 2024 | TMDL priority: Low |
| Phosphorus, Total | Aquatic Life | 2024 | TMDL priority: Low |
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.
- Dissolved Oxygen
- Natural Conditions - Water Quality Standards Use Attainability Analyses Needed (suspected)
Virginia also recorded the source of at least one listing here as unknown, including for Phosphorus, Total.
Reading the record
Where Lake Culpeper sits among peers
96% of Virginia's lakes assessed this deeply also came out mixed (the standard result at this depth, not a distinction)
Virginia ruled definitively on 4 designated uses at Lake Culpeper and found 1 of 4 not supported. The dataset shows 50 Virginia lakes judged to that same depth.
Virginia's assessed lakes are most often judged on 3 uses; this one was judged on 4.
Computed share from EPA ATTAINS filed records, not an official EPA rating or safety grade.
| 1 | 2 | 3 | 4 | 5+ | |
|---|---|---|---|---|---|
| All supported | 7 | 15 | 26 | 2 | 0 |
| Mixed | Not possible | 14 | 66 | 48 (this record) | 4 |
| None supported | 45 | 3 | 1 | 0 | 0 |
Ringed cell: Lake Culpeper. Source: EPA ATTAINS, Reporting cycles 1987–2026.
Scale and rank
Lake Culpeper is one of 275 lake-type waterbodies reported to EPA from Virginia, and one of 193 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 250 assessed acres it ranks 6,115th 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 6,114 lakes with a larger one.
Awaiting a filing
The state has not yet filed a definitive recreation verdict for this record; that field populates when it reports it in a future Integrated Report cycle.
Reported trophic class
Virginia carried the trophic field for this assessment unit and filed it as unclassified, which records that no class was determined rather than that the water is unenriched. What the trophic scale measures.
In context
Where Lake Culpeper 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
250 Top 16% larger than 84% 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 Lake Culpeper. Hover or tap any bar for its full count and share.
In context
Virginia context
ATTAINS carries 275 lake-type waterbodies in Virginia, 181 assessed as not supporting at least one use and 50 fully supporting. Among the 193 indexed units there, Lake Culpeper ranks 62nd by listed-cause count (2 listed causes) and 78th by assessed size among the 193 with an area filed; it sits in the not-supporting set (181 statewide) . Its listed causes include Dissolved Oxygen, which also appears among Virginia's most-filed impairment causes (led by PCBs in Fish Tissue). It also lists Phosphorus, Total, outside that top-five list.
| Other large assessed lakes in Virginia | Assessed acres |
|---|---|
| Kerr Reservoir Assessment unit VAW-L75L_ROA05M22 Not Supporting | 14,828 |
| Kerr Reservoir Assessment unit VAW-L75L_ROA05L98 Not Supporting | 7,018 |
| Kerr Reservoir Assessment unit VAW-L75L_ROA05N22 Not Supporting | 4,182 |
| Lake Drummond Not Supporting | 3,242 |
| Lake Chesdin Not Supporting | 3,164 |
| Lake Gaston Not Supporting | 3,072 |
Peers near Lake Culpeper's size or cause load
Similar assessed acres
Nearest filed extents (250 acres here).
- Grassy Lake · 250 acres · WI
- Clear Lake · 250 acres · WI
- Mill Lake · 250 acres · WI
- Stony · 250 acres · MN
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 VAN-E09L_MTN01A02. 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.