HydrionisGlobal Water Intelligence
Monitored reservoir

Brownlee Res At Brownlee Dam Id-Or State Line

United States Geological Survey reservoir gauge 13289700 in ID, with published storage from 1958.

Storage record13289700

Storage now, against this reservoir's own record

1,359.30 Mm³
Stored, September 2005
20th
Percentile among 47 Seps on record
-1.6%
Change over the 12 months to 2005-09

Storage in September 2005 was lower than most Seps on record, ranked against 47 other Seps held for this reservoir.

No percentage departure from the Sep average is published here. No long-term average is held for this month, so there is nothing to compare with.

Storage, 1958–2005

Monthly mean storage
566 monthly values, 1958 to 2005
Monthly mean storageMonthly mean storage: Brownlee Res At Brownlee Dam Id-Or State Line in Mm³, from 1958.3333333333333 to 2005.6666666666667.05001,0001,5002,000Mm³1958.33333333333331964.251970.16666666666671976.083333333333319821987.91666666666671993.83333333333332000Year

Monthly means of the publisher's daily record. Volume, not percentage of capacity — see below for why.

What the shaded periods are (0 events)

Not shown on this chart

  • The 1976 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
  • The 2022 drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
  • Yorkshire drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
  • Cantareira water crisis, São Paulo — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
  • Cape Town Day Zero — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
  • European drought — This event’s area does not contain this chart’s subject. Sharing a country is not sharing an event, so it is not drawn.
View the data behind this chart
240 of 566 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 566 would be longer than this page and unusable with a screen reader.
PeriodBrownlee Res At Brownlee Dam Id-Or State Line (Mm³)
May 1958335
July 1958656
October 19581,067
December 19581,239
February 19591,165
May 19591,288
July 19591,746
October 19591,688
December 19591,535
February 19601,156
May 19601,639
July 19601,712
September 19601,725
December 19601,574
February 19611,032
April 1961857
July 19611,705
September 19611,766
December 19611,651
February 19621,251
April 19621,219
July 19621,771
September 19621,761
November 19621,739
February 19631,574
April 19631,665
June 19631,755
September 19631,744
November 19631,721
February 1964835
April 1964993
June 19641,680
September 19641,750
November 19641,757
January 19651,443
April 1965687
June 19651,533
August 19651,722
November 19651,233
January 19661,103
April 19661,176
June 19661,750
August 19661,763
November 19661,755
January 19671,552
March 19671,073
June 19671,641
August 19671,754
October 19671,727
January 19681,442
March 19681,387
June 19681,748
August 19681,760
October 19681,756
January 19691,437
March 1969925
May 19691,231
August 19691,744
October 19691,745
December 19691,600
March 19701,134
May 19701,230
August 19701,765
October 19701,749
December 19701,663
March 1971865
May 1971832
July 19711,762
October 19711,736
December 19711,662
February 19721,361
May 1972610
July 19721,767
October 19721,737
December 19721,526
February 19731,208
May 19731,648
July 19731,714
September 19731,770
December 19731,704
February 19741,355
April 19741,110
July 19741,767
September 19741,743
December 19741,643
February 19751,373
April 19751,006
July 19751,747
September 19751,686
November 19751,764
February 19761,337
April 19761,258
June 19761,725
September 19761,750
November 19761,718
February 19771,439
April 19771,447
June 19771,670
September 19771,691
November 19771,672
January 19781,356
April 19781,148
June 19781,711
August 19781,684
November 19781,701
January 19791,312
April 19791,417
June 19791,678
August 19791,349
November 19791,615
January 19801,359
March 19801,379
June 19801,765
August 19801,591
October 19801,699
January 19811,548
March 19811,431
June 19811,763
August 19811,683
October 19811,666
January 19821,222
March 19821,267
May 19821,247
August 19821,740
October 19821,664
January 19831,656
March 19831,344
May 19831,275
August 19831,702
October 19831,636
December 19831,725
March 19841,295
May 19841,450
July 19841,744
October 19841,655
December 19841,507
March 1985994
May 19851,476
July 19851,401
October 19851,578
December 19851,546
February 19861,448
May 19861,440
July 19861,742
September 19861,703
December 19861,699
February 19871,359
May 19871,637
July 19871,734
September 19871,615
December 19871,574
February 19881,256
April 19881,473
July 19881,744
September 19881,707
November 19881,744
February 19891,133
April 19891,264
July 19891,691
September 19891,515
November 19891,638
February 19901,410
April 19901,481
June 19901,738
September 19901,572
November 19901,709
January 19911,516
April 19911,655
June 19911,737
September 19911,577
November 19911,560
January 19921,642
April 19921,721
June 19921,722
August 19921,503
November 19921,456
January 19931,587
March 19931,471
June 19931,737
August 19931,463
November 19931,255
January 19941,595
March 19941,643
June 19941,708
August 19941,477
October 19941,437
January 19951,632
March 19951,445
May 19951,613
August 19951,461
October 19951,172
January 19961,521
March 19961,384
May 19961,267
August 19961,332
October 19961,167
December 19961,707
March 1997913
May 1997814
July 19971,717
October 1997800
December 19971,569
March 19981,315
May 19981,732
July 19981,597
October 1998889
December 19981,702
April 1999701
July 19991,597
October 19991,106
December 19991,569
March 20001,393
May 20001,506
August 20001,255
October 20001,240
December 20001,580
March 20011,680
May 20011,735
July 20011,674
October 20011,372
December 20011,649
February 20021,207
May 20021,639
July 20021,675
October 20021,227
December 20021,504
February 20031,655
May 20031,691
July 20031,697
September 20031,297
December 20031,510
February 20041,317
April 20041,508
July 20041,645
September 20041,382
December 20041,687
February 20051,611
April 20051,677
July 20051,554
September 20051,359

Why this page shows a volume and not a percentage

Rate and persistence

-1.86 Mm³
Mean drawdown per month over 12 months
6 of 24
Recent months below the 20th percentile for their own month

Rates are computed only across an unbroken run of months, so a rate is never divided by a period in which some of the change was not observed. Percentile counts compare each month with the same calendar month in every other year held.

Location

Brownlee Res At Brownlee Dam Id-Or State Line
Gauge location
Brownlee Res At Brownlee Dam Id-Or State LineBrownlee Res At Brownlee Dam Id-Or State Line — 1,359.30 Mm³Brownlee Res At Brownlee Dam Id-Or State Line — 1,359.30 Mm³

About this data

About this data

Everything below is a property of the data rather than a rating of it. There is deliberately no single confidence score: how much a gap matters depends on what you are about to do with the series, and only you know that.

Source
United States Geological Survey — National Water Information System · US Government work — public domain
How the values came to existMeasured
Period held1958–2005
Completeness98.3% of the periods in that span are held. Gaps are drawn as breaks and never interpolated.
Known gaps
  • Storage is a managed quantity. A falling line can be a rule curve, a scheduled release or a transfer to another system rather than a shortage of water, and nothing here distinguishes them.
  • No capacity figure on a stated basis is held for this reservoir, so no percentage of capacity is computed.
Continuity98% of the months between 1958 and 2005 are held. Monthly means of the publisher's own daily record.
Last read from the publisher2026-10-01
RedistributionPermitted by the upstream licences
Commercial reusePermitted by the upstream licences. No Hydrionis access tier can widen this.
MethodologyHow this was produced

Use this data

Use this data

No bulk download is offered here, which is a licence position rather than a product one: at least one contributing publisher does not permit redistribution. The values can be read on the page, cited, and pointed to at source.

Attribution and citation

Suggested citation for Hydrionis

Hydrionis (2026), Brownlee Res At Brownlee Dam Id-Or State Line reservoir records, accessed 2026-10-05, hydrionis.com/reservoirs/reservoir-usgs-13289700/

Cite Hydrionis where you rely on the compilation, the normalisation, the eligibility judgements or a chart. Where you use an unmodified published value, the publisher’s attribution is the one that is required; crediting Hydrionis as well is welcome and is not something Hydrionis can require of you.

Recommended, not required. Hydrionis does not claim rights over unmodified public data it relayed, and doing arithmetic on somebody else’s measurements does not make them Hydrionis’s. Cite the version and the access date: the Brownlee Res At Brownlee Dam Id-Or State Line record changes as publishers release and as methods are revised, and a citation without both cannot be checked later. Full guidance is on cite and reuse.

None of the contributing licences requires attribution. Crediting the publishers is still good practice and they are listed above.

Where this comes from

566 monthly observations 1958–2005 Mm³
Spatially aggregatedHigh confidenceSeptember 2005

Source: USGS — National Water Information System, 13289700. Licence: Open.

Method: Monthly mean of daily reservoir storage published by the USGS in acre-feet and converted to millions of cubic metres. Months with fewer than 20 days of record are not published rather than averaged from a partial month.

Reservoir storage is managed as well as observed: a drawdown may reflect an operating rule, flood-control rule curve or scheduled release rather than a shortage. Compare a month against the same month in other years, and do not read a fall as a supply signal without knowing the operating regime.

Retrieved 1 October 2026.

Monthly mean of daily reservoir storage published by the USGS in acre-feet and converted to millions of cubic metres. Months with fewer than 20 days of record are not published rather than averaged from a partial month.

Hydrionis would like to measure which pages are read, using HEKNO Analytics, which HEKNO Ltd runs itself, and Google Analytics. Google Analytics stores an identifier on your device, so we only do this if you agree. Nothing is measured if you decline, and the site works identically either way. See cookies for what is set and how to change your mind.