Nevada reservoir · state assessment record
Spooner Lake - Lake Tahoe Tributaries
Assessment decisions reported by Nevada to EPA under Clean Water Act sections 303(d) and 305(b), last assessed in the 2022 reporting cycle.
- 86
- Assessed acres
- Reservoir
- Water type
This waterbody in one line
Spooner Lake - Lake Tahoe Tributaries, a reservoir in Nevada, is assessed as not supporting one or more designated uses, with 3 listed impairment causes in the state's most recent Integrated Report cycle (2022). By assessed acreage it sits above the national median by assessed acreage (38,628 lakes); its impairment list is among the longest nationally (3 listed causes vs 23,610 assessed lakes). Aquatic life is assessed as not supporting.
- Not Supporting
- overall status
- P67
- Assessed size nationally
- P5
- 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.
Spooner Lake - Lake Tahoe Tributaries 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: 3 listed impairment causes, a longer list than 90% of assessed lake-type units (n=23,610). List length tracks how states sample and code, not a severity score.
Every ruled-on use is not supporting
On the uses this filer ruled on, aquatic life, every determination is Not Supporting. That is a use-by-use reading of the filed record, not a single overall lake grade.
Spooner Lake - Lake Tahoe Tributaries: Category 5, TMDL still owed
Category 5 is the Integrated Report band where a TMDL (or equivalent) is still expected for Spooner Lake - Lake Tahoe Tributaries. 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 Spooner Lake - Lake Tahoe Tributaries is Not Supporting. That tile summarizes the assessment unit; the designated-use rows and cause list are the evidence behind it.
Large assessed unit
At 86.5 acres, Spooner Lake - Lake Tahoe Tributaries clears the upper tercile of assessed lake-type units with an area on file (12,870 still larger). Size comparisons use the portal's deduplicated lake ranking population, not raw ATTAINS row counts.
According to the U.S. Environmental Protection Agency's ATTAINS program, Nevada carries 69 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Spooner Lake - Lake Tahoe Tributaries 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. Monitoring behind at least one of these designated-use verdicts ran through 2022, as Nevada filed it. Nevada filed its own confidence on the 4 definitive verdicts it rated: Low. 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: Low |
| Irrigation | Other | Fully Supporting Filer confidence: Low |
| Municipal or Domestic Supply | Drinking-water supply designation | Fully Supporting Filer confidence: Low |
| Watering of Livestock | Other | Fully Supporting Filer confidence: Low |
| Enhancement of Water Quality | Other | Not Assessed |
| Industrial Supply | Other | Insufficient Information Filer confidence: Low |
| Propagation of Wildlife | Other | Insufficient Information Filer confidence: Low |
| Recreation Involving Contact with the Water | Recreation | Insufficient Information Filer confidence: Low |
| Recreation Not Involving Contact with the Water | Recreation | Insufficient Information Filer confidence: Low |
| Water and Organisms | Aquatic-life or related | Not Assessed |
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 |
|---|---|---|---|
| Temperature | Aquatic Life | 2024 | TMDL priority: Low |
| Turbidity | Aquatic Life | 2024 | TMDL priority: Low |
| pH | Aquatic Life Also assessed as meeting: Industrial Supply | 2024 | TMDL priority: Low |
Reading the record
Where Spooner Lake - Lake Tahoe Tributaries sits among peers
1 of 1 Nevada lakes assessed this deeply also came out mixed (every lake judged to this depth, so the outcome does not set this record apart)
Nevada ruled definitively on 4 designated uses at Spooner Lake - Lake Tahoe Tributaries and found 1 of 4 not supported. The dataset shows 1 Nevada lakes judged to that same depth.
Nevada's assessed lakes are most often judged on 5 or more uses; this one was judged on 4.
| 1 | 2 | 3 | 4 | 5+ | |
|---|---|---|---|---|---|
| All supported | 2 | 1 | 1 | 0 | 13 |
| Mixed | Not possible | 1 | 1 | 1 (this record) | 30 |
| None supported | 3 | 0 | 0 | 0 | 0 |
Ringed cell: Spooner Lake - Lake Tahoe Tributaries. Source: EPA ATTAINS, Reporting cycles 1987–2026.
Scale and rank
Spooner Lake - Lake Tahoe Tributaries is one of 69 lake-type waterbodies reported to EPA from Nevada, and one of 50 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 86 assessed acres it ranks 12,871st 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 12,870 lakes with a larger one.
Still unfiled
The state has not yet filed a definitive fish-consumption verdict and a definitive recreation verdict for this record; those fields populate when it reports them in a future Integrated Report cycle.
In context
Where Spooner Lake - Lake Tahoe Tributaries 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
86 Top 33% larger than 67% 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
3 Longer than most more listed causes than 90% 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 Spooner Lake - Lake Tahoe Tributaries. Hover or tap any bar for its full count and share.
In context
Nevada context
ATTAINS carries 69 lake-type waterbodies in Nevada, 36 assessed as not supporting at least one use and 17 fully supporting. Among the 50 indexed units there, Spooner Lake - Lake Tahoe Tributaries ranks 12th by listed-cause count (3 listed causes) and 26th by assessed size among the 50 with an area filed; it sits in the not-supporting set (36 statewide) . Its listed causes include Temperature, which also appears among Nevada's most-filed impairment causes (led by Phosphorus). It also lists Turbidity and pH, outside that top-five list.
| Other large assessed lakes in Nevada | Assessed acres |
|---|---|
| Lake Mead Fully Supporting | 147,392 |
| Lake Tahoe Not Supporting | 122,902 |
| Walker Lake Not Supporting | 35,521 |
| Lake Mohave Not Supporting | 27,001 |
| Rye Patch Reservoir Not Supporting | 16,001 |
| Lahontan Reservoir Not Supporting | 14,178 |
Peers near Spooner Lake - Lake Tahoe Tributaries's size or cause load
Similar assessed acres
Nearest filed extents (86 acres here).
- Sprague Lake · 86 acres · WA
- Lake Annie (Modoc County) · 86 acres · CA
- Roosevelt Lake · 86 acres · SD
- Hatfield Lake · 86 acres · WI
Similar cause load
Nearest listed-cause counts (3 here). Peers already in the acreage column are omitted.
- 67th St. Beach · 3 causes · IL
- Abiquiu Reservoir · 3 causes · NM
- Absecon Creek (AC Reserviors) (gage to SB) · 3 causes · NJ
- Absecon Creek (below gage) · 3 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 NV06-TB-25_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.