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.

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: without a capacity whose definition is stated, fullness cannot be computed.

View the data behind this chart
Underlying data
PeriodBrownlee Res At Brownlee Dam Id-Or State Line (Mm³)
May 1958335
June 1958438
July 1958656
August 1958817
September 19581,031
October 19581,067
November 19581,145
December 19581,239
January 19591,247
February 19591,165
March 19591,078
April 1959956
May 19591,288
June 19591,695
July 19591,746
August 19591,755
September 19591,730
October 19591,688
November 19591,617
December 19591,535
January 19601,336
February 19601,156
March 19601,050
April 19601,538
May 19601,639
June 19601,739
July 19601,712
August 19601,748
September 19601,725
October 19601,722
November 19601,621
December 19601,574
January 19611,236
February 19611,032
March 1961847
April 1961857
May 19611,212
June 19611,647
July 19611,705
August 19611,754
September 19611,766
October 19611,761
November 19611,755
December 19611,651
January 19621,467
February 19621,251
March 19621,126
April 19621,219
May 19621,406
June 19621,631
July 19621,771
August 19621,757
September 19621,761
October 19621,753
November 19621,739
December 19621,750
January 19631,529
February 19631,574
March 19631,446
April 19631,665
May 19631,701
June 19631,755
July 19631,757
August 19631,758
September 19631,744
October 19631,711
November 19631,721
December 19631,585
January 19641,190
February 1964835
March 1964688
April 1964993
May 19641,153
June 19641,680
July 19641,757
August 19641,760
September 19641,750
October 19641,748
November 19641,757
December 19641,734
January 19651,443
February 19651,381
March 1965723
April 1965687
May 1965674
June 19651,533
July 19651,761
August 19651,722
September 19651,625
October 19651,397
November 19651,233
December 19651,200
January 19661,103
February 1966880
March 1966958
April 19661,176
May 19661,519
June 19661,750
July 19661,765
August 19661,763
September 19661,768
October 19661,769
November 19661,755
December 19661,709
January 19671,552
February 19671,252
March 19671,073
April 1967935
May 19671,056
June 19671,641
July 19671,756
August 19671,754
September 19671,757
October 19671,727
November 19671,747
December 19671,665
January 19681,442
February 19681,322
March 19681,387
April 19681,382
May 19681,389
June 19681,748
July 19681,763
August 19681,760
September 19681,754
October 19681,756
November 19681,754
December 19681,679
January 19691,437
February 19691,387
March 1969925
April 1969830
May 19691,231
June 19691,713
July 19691,760
August 19691,744
September 19691,746
October 19691,745
November 19691,722
December 19691,600
January 19701,550
February 19701,452
March 19701,134
April 19701,132
May 19701,230
June 19701,732
July 19701,759
August 19701,765
September 19701,762
October 19701,749
November 19701,717
December 19701,663
January 19711,589
February 19711,492
March 1971865
April 1971664
May 1971832
June 19711,591
July 19711,762
August 19711,765
September 19711,728
October 19711,736
November 19711,654
December 19711,662
January 19721,599
February 19721,361
March 19721,285
April 1972641
May 1972610
June 19721,483
July 19721,767
August 19721,760
September 19721,749
October 19721,737
November 19721,691
December 19721,526
January 19731,404
February 19731,208
March 19731,179
April 19731,417
May 19731,648
June 19731,756
July 19731,714
August 19731,754
September 19731,770
October 19731,758
November 19731,754
December 19731,704
January 19741,633
February 19741,355
March 19741,183
April 19741,110
May 1974845
June 19741,555
July 19741,767
August 19741,759
September 19741,743
October 19741,721
November 19741,636
December 19741,643
January 19751,550
February 19751,373
March 19751,091
April 19751,006
May 1975984
June 19751,603
July 19751,747
August 19751,764
September 19751,686
October 19751,688
November 19751,764
December 19751,750
January 19761,695
February 19761,337
March 19761,121
April 19761,258
May 19761,361
June 19761,725
July 19761,764
August 19761,751
September 19761,750
October 19761,740
November 19761,718
December 19761,611
January 19771,451
February 19771,439
March 19771,512
April 19771,447
May 19771,490
June 19771,670
July 19771,594
August 19771,595
September 19771,691
October 19771,735
November 19771,672
December 19771,686
January 19781,356
February 19781,206
March 19781,095
April 19781,148
May 19781,355
June 19781,711
July 19781,738
August 19781,684
September 19781,690
October 19781,691
November 19781,701
December 19781,556
January 19791,312
February 19791,259
March 19791,349
April 19791,417
May 19791,580
June 19791,678
July 19791,363
August 19791,349
September 19791,590
October 19791,677
November 19791,615
December 19791,426
January 19801,359
February 19801,199
March 19801,379
April 19801,418
May 19801,694
June 19801,765
July 19801,720
August 19801,591
September 19801,686
October 19801,699
November 19801,684
December 19801,565
January 19811,548
February 19811,463
March 19811,431
April 19811,596
May 19811,744
June 19811,763
July 19811,719
August 19811,683
September 19811,626
October 19811,666
November 19811,698
December 19811,618
January 19821,222
February 19821,241
March 19821,267
April 19821,042
May 19821,247
June 19821,693
July 19821,762
August 19821,740
September 19821,702
October 19821,664
November 19821,685
December 19821,740
January 19831,656
February 19831,509
March 19831,344
April 19831,112
May 19831,275
June 19831,704
July 19831,743
August 19831,702
September 19831,524
October 19831,636
November 19831,731
December 19831,725
January 19841,614
February 19841,334
March 19841,295
April 19841,313
May 19841,450
June 19841,609
July 19841,744
August 19841,701
September 19841,633
October 19841,655
November 19841,661
December 19841,507
January 19851,321
February 19851,200
March 1985994
April 19851,099
May 19851,476
June 19851,691
July 19851,401
August 19851,485
September 19851,602
October 19851,578
November 19851,545
December 19851,546
January 19861,476
February 19861,448
March 19861,461
April 19861,266
May 19861,440
June 19861,755
July 19861,742
August 19861,736
September 19861,703
October 19861,717
November 19861,667
December 19861,699
January 19871,529
February 19871,359
March 19871,500
April 19871,637
May 19871,637
June 19871,733
July 19871,734
August 19871,658
September 19871,615
October 19871,654
November 19871,687
December 19871,574
January 19881,337
February 19881,256
March 19881,273
April 19881,473
May 19881,568
June 19881,738
July 19881,744
August 19881,698
September 19881,707
October 19881,735
November 19881,744
December 19881,711
January 19891,491
February 19891,133
March 19891,260
April 19891,264
May 19891,290
June 19891,676
July 19891,691
August 19891,558
September 19891,515
October 19891,567
November 19891,638
December 19891,696
January 19901,629
February 19901,410
March 19901,324
April 19901,481
May 19901,653
June 19901,738
July 19901,751
August 19901,705
September 19901,572
October 19901,587
November 19901,709
December 19901,676
January 19911,516
February 19911,542
March 19911,535
April 19911,655
May 19911,675
June 19911,737
July 19911,687
August 19911,726
September 19911,577
October 19911,426
November 19911,560
December 19911,695
January 19921,642
February 19921,651
March 19921,705
April 19921,721
May 19921,654
June 19921,722
July 19921,602
August 19921,503
September 19921,470
October 19921,409
November 19921,456
December 19921,556
January 19931,587
February 19931,449
March 19931,471
April 19931,740
May 19931,740
June 19931,737
July 19931,675
August 19931,463
September 19931,358
October 19931,110
November 19931,255
December 19931,490
January 19941,595
February 19941,546
March 19941,643
April 19941,715
May 19941,566
June 19941,708
July 19941,560
August 19941,477
September 19941,472
October 19941,437
November 19941,474
December 19941,604
January 19951,632
February 19951,564
March 19951,445
April 19951,493
May 19951,613
June 19951,742
July 19951,721
August 19951,461
September 19951,327
October 19951,172
November 19951,377
December 19951,693
January 19961,521
February 19961,560
March 19961,384
April 19961,059
May 19961,267
June 19961,739
July 19961,660
August 19961,332
September 19961,366
October 19961,167
November 19961,440
December 19961,707
January 19971,713
February 19971,330
March 1997913
April 1997710
May 1997814
June 19971,627
July 19971,717
August 19971,475
September 19971,256
October 1997800
November 19971,164
December 19971,569
January 19981,675
February 19981,442
March 19981,315
April 19981,606
May 19981,732
June 19981,742
July 19981,597
August 19981,262
September 19981,092
October 1998889
November 19981,203
December 19981,702
January 19991,576
April 1999701
May 1999848
June 19991,581
July 19991,597
August 19991,310
October 19991,106
November 19991,290
December 19991,569
January 20001,643
February 20001,430
March 20001,393
April 20001,404
May 20001,506
June 20001,703
July 20001,450
August 20001,255
September 20001,266
October 20001,240
November 20001,488
December 20001,580
January 20011,642
February 20011,574
March 20011,680
April 20011,706
May 20011,735
June 20011,733
July 20011,674
August 20011,471
September 20011,350
October 20011,372
November 20011,538
December 20011,649
January 20021,525
February 20021,207
March 20021,215
April 20021,372
May 20021,639
June 20021,733
July 20021,675
August 20021,549
September 20021,345
October 20021,227
November 20021,364
December 20021,504
January 20031,665
February 20031,655
March 20031,586
April 20031,632
May 20031,691
June 20031,736
July 20031,697
August 20031,509
September 20031,297
October 20031,202
November 20031,338
December 20031,510
January 20041,465
February 20041,317
March 20041,319
April 20041,508
May 20041,714
June 20041,727
July 20041,645
August 20041,499
September 20041,382
October 20041,391
November 20041,566
December 20041,687
January 20051,643
February 20051,611
March 20051,685
April 20051,677
May 20051,739
June 20051,726
July 20051,554
August 20051,381
September 20051,359

Rate and persistence

-1.86 Mm³
Mean drawdown per month over 12 months
6 of 24
Months in the last two years 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

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 25 August 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.

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