Utah lake · state assessment record
Provo Bay portion of Utah Lake
Assessment decisions reported by Utah to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2024 reporting cycle.
- 3,612
- Assessed acres
- Lake, Freshwater
- Water type
This waterbody in one line
Provo Bay portion of Utah Lake, a lake in Utah, is assessed as not supporting one or more designated uses, with 6 listed impairment causes in the state's most recent Integrated Report cycle (2024). By assessed acreage it sits among the largest 5% by assessed acreage nationally (38,628 lakes); its impairment list is among the longest nationally (6 listed causes vs 23,610 assessed lakes). Aquatic life is assessed as not supporting.
- Not Supporting
- overall status
- P98
- Assessed size nationally
- P1
- 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.
Provo Bay portion of Utah Lake against the ATTAINS 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: cause-list length
The standout filed fact is cause-list length: 6 listed impairment causes, a longer list than 99% of assessed lake-type units (n=23,610). List length tracks how states sample and code, not a severity score.
Large assessed unit
At 3,612 acres, Provo Bay portion of Utah Lake clears the upper tercile of assessed lake-type units with an area on file (842 still larger). Size comparisons use the portal's deduplicated lake ranking population, not raw ATTAINS row counts.
No ruled-on use clears the bar
On the uses this filer ruled on, recreation, aquatic life, every determination is Not Supporting. That is a use-by-use reading of the filed record, not a single overall lake grade.
Provo Bay portion of Utah Lake: Category 5, TMDL still owed
Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Provo Bay portion of Utah Lake. Read the listed causes and any cleanup actions filed beside them before treating the overall status tile as a finished restoration story.
Large within Utah
Among Utah's 84 indexed units with an area, Provo Bay portion of Utah Lake ranks 8 by assessed size, toward the large end of that state file.
According to the U.S. Environmental Protection Agency's ATTAINS program, Utah carries 143 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Provo Bay portion of Utah Lake 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 |
|---|---|---|
| Agricultural | Other | Fully Supporting |
| Aquatic Wildlife (Warm Water) | Aquatic-life or related | Not Supporting |
| Aquatic Wildlife (Waterfowl, Shorebirds, and Other) | Aquatic-life or related | Not Supporting |
| Recreation and Aesthetics (Frequent Primary Contact) | Recreation | Not Supporting |
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 |
|---|---|---|---|
| Phosphorus, Total | Aquatic Wildlife (Warm Water) | 1994 | TMDL priority: Low |
| PCBs in Fish Tissue | Aquatic Wildlife (Warm Water) | 2010 | TMDL priority: Low |
| pH | Aquatic Wildlife (Warm Water) | 2016 | TMDL priority: Low |
| Eutrophication | Aquatic Wildlife (Warm Water) | 2020 | TMDL priority: Low |
| Harmful Algal Blooms | Recreation and Aesthetics (Frequent Primary Contact) | 2020 | TMDL priority: Low |
| Ammonia, Total | Aquatic Wildlife (Warm Water); Aquatic Wildlife (Waterfowl, Shorebirds, and Other) | 2024 | TMDL priority: Low |
Probable sources
Utah 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 Provo Bay portion of Utah Lake sits among peers
9 of 12 Utah lakes assessed this deeply also came out mixed
Utah ruled definitively on 4 designated uses at Provo Bay portion of Utah Lake and found 3 of 4 not supported. The dataset shows 12 Utah lakes judged to that same depth.
Utah's assessed lakes are most often judged on 2 uses; this one was judged on 4.
| 1 | 2 | 3 | 4 | 5+ | |
|---|---|---|---|---|---|
| All supported | 28 | 27 | 2 | 3 | 0 |
| Mixed | Not possible | 29 | 21 | 9 (this record) | 1 |
| None supported | 14 | 2 | 1 | 0 | 0 |
Ringed cell: Provo Bay portion of Utah Lake. Source: EPA ATTAINS, Reporting cycles 1987–2026.
Scale and rank
Provo Bay portion of Utah Lake is one of 143 lake-type waterbodies reported to EPA from Utah, and one of 84 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 3,612 assessed acres it ranks 843rd 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 842 lakes with a larger one.
Still unfiled
The state has not yet filed a definitive fish-consumption verdict for this record; that field populates when it reports it in a future Integrated Report cycle.
In context
Where Provo Bay portion of Utah 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
3,612 Top 2% larger than 98% 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
6 Longer than most more listed causes than 99% 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 Provo Bay portion of Utah Lake. Hover or tap any bar for its full count and share.
In context
Utah context
ATTAINS carries 143 lake-type waterbodies in Utah, 77 assessed as not supporting at least one use and 60 fully supporting. Among the 84 indexed units there, Provo Bay portion of Utah Lake ranks 2nd by listed-cause count (6 listed causes) and 8th by assessed size among the 84 with an area filed; it sits in the not-supporting set (77 statewide) . Its listed causes include Phosphorus, Total; pH; and Harmful Algal Blooms, which also appear among Utah's most-filed impairment causes (led by pH). It also lists PCBs in Fish Tissue; Eutrophication; and Ammonia, Total, outside that top-five list.
| Other large assessed lakes in Utah | Assessed acres |
|---|---|
| Gilbert Bay Fully Supporting | 559,424 |
| Gunnison Bay Not Assessed | 384,588 |
| Lake Powell Fully Supporting | 149,885 |
| Utah Lake other than Provo Bay Not Supporting | 87,984 |
| Farmington Bay Not Assessed | 77,243 |
| Bear River Bay Not Assessed | 71,681 |
Peers near Provo Bay portion of Utah Lake's size or cause load
Similar assessed acres
Nearest filed extents (3,612 acres here).
- Big Cormorant · 3,613 acres · MN
- Whiteface Reservoir · 3,613 acres · MN
- Carrabassett River · 3,615 acres · ME
- YADKIN RIVER (including Tuckertown Lake, Badin Lake) · 3,617 acres · NC
Similar cause load
Nearest listed-cause counts (6 here). Peers already in the acreage column are omitted.
- Allegan Lake · 6 causes · MI
- Almonesson Creek · 6 causes · NJ
- Ambrose Brook (below Lake Nelson) · 6 causes · NJ
- Assunpink Ck (below Shipetaukin Ck) · 6 causes · NJ
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 UT-L-16020201-004_02. 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.