Pennsylvania reservoir · state assessment record
Chapman Dam Lake-05010003001310
Assessment decisions reported by Pennsylvania to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2026 reporting cycle.
- 67
- Assessed acres
- Lake / Reservoir / Pond
- Water type
This waterbody in one line
Chapman Dam Lake-05010003001310, a reservoir in Pennsylvania, is assessed as not supporting one or more designated uses, with one listed impairment cause in the state's most recent Integrated Report cycle (2026). By assessed acreage it sits above the national median by assessed acreage (38,628 lakes); its impairment list is among the longest nationally (one listed cause vs 23,610 assessed lakes). Pennsylvania assesses fishing as not supported; it reported no verdict on fish consumption itself.
- Not Supporting
- overall status
- P61
- Assessed size nationally
- P20
- 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.
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.
Reading Chapman Dam Lake-05010003001310'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: assessed size
Assessed size is not the extreme here: 67 acres sits near the middle of the 38,628 units with an area filed (percentile 61).
The uses disagree
This record splits: Not Supporting on fish consumption, Fully Supporting on recreation. The divergence is inside the designated-use matrix, not a single all-or-nothing label.
Chapman Dam Lake-05010003001310: Category 5, TMDL still owed
Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Chapman Dam Lake-05010003001310. Read the listed causes and any cleanup actions filed beside them before treating the overall status tile as a finished restoration story.
Overall status: not supporting
The filer's overall status for Chapman Dam Lake-05010003001310 is Not Supporting. That tile summarizes the assessment unit; the designated-use rows and cause list are the evidence behind it.
Typical cause-list length
1 listed cause is a middle-tercile list length among assessed lake-type units. Look to IR category and use outcomes for the distinctive reading.
According to the U.S. Environmental Protection Agency's ATTAINS program, Pennsylvania carries 516 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Chapman Dam Lake-05010003001310 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 |
|---|---|---|
| Aesthetics | Other | Fully Supporting |
| Boating | Recreation | Fully Supporting |
| Fishing | Fish-consumption or fishery | Not Supporting |
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 |
|---|---|---|---|
| Mercury | Fishing | 2026 | TMDL priority: Medium |
Probable sources
Pennsylvania 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 Chapman Dam Lake-05010003001310 sits among peers
35% of Pennsylvania's lakes assessed this deeply also came out mixed
Pennsylvania ruled definitively on 3 designated uses at Chapman Dam Lake-05010003001310 and found 1 of 3 not supported. The dataset shows 51 Pennsylvania lakes judged to that same depth.
Pennsylvania's assessed lakes are most often judged on 2 uses; this one was judged on 3.
Computed share from EPA ATTAINS filed records, not an official EPA rating or safety grade.
| 1 | 2 | 3 | 4 | 5+ | |
|---|---|---|---|---|---|
| All supported | 98 | 154 | 30 | 65 | 34 |
| Mixed | Not possible | 15 | 18 (this record) | 20 | 44 |
| None supported | 32 | 3 | 3 | 0 | 0 |
Ringed cell: Chapman Dam Lake-05010003001310. Source: EPA ATTAINS, Reporting cycles 1987–2026.
Scale and rank
Chapman Dam Lake-05010003001310 is one of 516 lake-type waterbodies reported to EPA from Pennsylvania, and one of 246 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 67 assessed acres it ranks 14,983rd 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 14,982 lakes with a larger one.
Still unfiled
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 Chapman Dam Lake-05010003001310 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
67 Top 39% larger than 61% 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
1 Longer than most more listed causes than 49% 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 Chapman Dam Lake-05010003001310. Hover or tap any bar for its full count and share.
In context
Pennsylvania context
ATTAINS carries 516 lake-type waterbodies in Pennsylvania, 135 assessed as not supporting at least one use and 381 fully supporting. Among the 246 indexed units there, Chapman Dam Lake-05010003001310 ranks 98th by listed-cause count (one listed cause) and 135th by assessed size among the 246 with an area filed; it sits in the not-supporting set (135 statewide) . Its listed causes include Mercury, which also appears among Pennsylvania's most-filed impairment causes (led by Mercury).
| Other large assessed lakes in Pennsylvania | Assessed acres |
|---|---|
| Pymatuning Reservoir-05030102001826 Not Supporting | 15,995 |
| Allegheny Reservoir-05010001002698 Not Supporting | 12,211 |
| Raystown Lake-02050303001006 Fully Supporting | 8,127 |
| Lake Clark-02050306012077 Fully Supporting | 8,117 |
| Lake Wallenpaupack-02040103001053 Not Supporting | 5,461 |
| Presque Isle Bay-04120101000933 Not Supporting | 3,655 |
Peers near Chapman Dam Lake-05010003001310's size or cause load
Similar assessed acres
Nearest filed extents (67 acres here).
- Alloway Ck (Quinton to Alloway-WdstwnRd) · 67 acres · NJ
- Twenty-Eight · 67 acres · MN
- Goose Lake · 67 acres · WI
- Mud · 67 acres · MN
Similar cause load
Nearest listed-cause counts (1 here). Peers already in the acreage column are omitted.
- Aaron · 1 causes · MN
- Aaron River Reservoir · 1 causes · MA
- Abbotts Creek (including Lexington-Thomasville Water Supply Reservoir at normal reservoir elevation, Tom-A-Lex Lake) · 1 causes · NC
- Abeniki Lake · 1 causes · NH
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 reservoir. Your state fish-advisory program is the source for whether the catch is safe to eat. 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 PA-LRP-05010003001310. 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.