Oregon reservoir · state assessment record
Harney Lake
The assessment record reported by Oregon to EPA under Clean Water Act sections 303(d) and 305(b).
- 31,369
- Assessed acres
- Lake / Reservoir / Pond
- Water type
This waterbody in one line
Harney Lake, a reservoir in Oregon, has no overall assessment verdict in the state's most recent Integrated Report. By assessed acreage it sits among the largest 1% of assessed lakes nationally (38,628 lakes with a filed area).
- Not reported
- overall status
- P100
- Assessed size nationally
Assessment verdicts are the state agency's decisions as reported to EPA ATTAINS; PlainLakes renders them without modification.
Where Harney Lake stands in 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 Harney Lake nationally is assessed size: 31,369 acres, larger than 100% of the 38,628 lake-type units with an area on file.
According to the U.S. Environmental Protection Agency's ATTAINS program, Oregon carries 1,431 filed lake-type waterbodies in the August 2026 extract, and this page renders the assessment record EPA assigned to Harney Lake without modification. See our methodology for reporting-unit limits and gauge linking rules.
The record
Listed impairment causes
No causes are listed because this reservoir has no overall assessment verdict in the reported cycle. An unassessed waterbody is neither confirmed clean nor confirmed impaired.
Reading the record
What Harney Lake's record holds
Scale and rank
Harney Lake is one of 1,431 lake-type waterbodies reported to EPA from Oregon. It is not among the 167 whose reported record carries enough populated assessment or gauge data for this site to list and index it. At 31,369 assessed acres it ranks 95th 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 94 lakes with a larger one.
Which uses were judged
Oregon filed no use-level rows for this reservoir and reached no overall verdict, so nothing here was judged either way.
What this record holds
Oregon filed no overall verdict, no reporting cycle and no EPA category for this reservoir, so the record holds the identifying fields above and no judgement of any kind: no verdict, and no impairment cause to track over time. The state has not yet filed a definitive fish-consumption verdict, a definitive recreation verdict, a definitive aquatic-life verdict, and 1 other for this record; those fields populate when it reports them in a future Integrated Report cycle.
Why no water-level record
Harney Lake has no daily USGS water-level or reservoir-storage series on this page because NWIS lists a lake monitoring site named for the waterbody, but the site is not active, and PlainLakes ingests only the active inventory, so there is no series to attach. How PlainLakes links gauges.
In context
Where Harney 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
31,369 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
In both charts each bar is a band and taller bars hold more waterbodies; the dashed line and filled bar mark Harney Lake. Hover or tap any bar for its full count and share.
In context
Oregon context
ATTAINS carries 1,431 lake-type waterbodies in Oregon, 165 assessed as not supporting at least one use and 14 fully supporting.
| Other large assessed lakes in Oregon | Assessed acres |
|---|---|
| Goose Lake Not reported | 93,152 |
| Malheur Slough Not Supporting | 73,544 |
| Upper Klamath Lake Not Supporting | 62,130 |
| Columbia River Not Supporting | 55,630 |
| Lake Abert Not Assessed | 44,751 |
| Summer Lake Not reported | 31,606 |
Lakes near Harney Lake's assessed acres
Similar assessed acres
Nearest filed extents (31,369 acres here).
- CATAWBA RIVER (Lake Norman below elevation 760) · 31,332 acres · NC
- West Grand Lake · 31,174 acres · ME
- Texoma Lake, Red River Arm, Lower · 31,081 acres · OK
- American Falls Reservoir (Snake River) · 31,724 acres · ID
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 OR_LK_1712000107_09_100913. 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.