Keechelus Lake — storage

Storage now, against this reservoir's own record

46.98 Mm³

Stored, August 2026

20th

Percentile among 121 Augs on record

-37.5%

Against the Aug 1991–2020 average

+132.5%

Change over the 12 months to 2026-08

Storage in August 2026 was lower than most Augs on record, ranked against 121 other Augs held for this reservoir.

Storage, 1906–2026

Monthly mean storage

1,448 monthly values, 1906 to 2026

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 1,448 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 1,448 would be longer than this page and unusable with a screen reader.
Period	Keechelus Lake (Mm³)
January 1906	2.55
July 1906	2.18
January 1907	7.21
July 1907	20.2
January 1908	9.33
July 1908	20.9
January 1909	20.5
July 1909	20.8
January 1910	20.5
July 1910	20.2
February 1911	20.2
August 1911	7.97
February 1912	20.7
August 1912	15.3
February 1913	20.6
August 1913	12.2
February 1914	14.7
August 1914	21.8
February 1915	33.3
August 1915	23.6
February 1916	12.6
August 1916	24.8
February 1917	27.6
August 1917	74.8
February 1918	48.0
August 1918	61.5
February 1919	34.2
August 1919	113
March 1920	112
September 1920	16.8
March 1921	119
September 1921	46.4
March 1922	140
September 1922	11.0
March 1923	98.4
September 1923	28.9
March 1924	126
September 1924	15.6
March 1925	127
September 1925	39.9
March 1926	125
September 1926	5.83
March 1927	83.1
September 1927	75.3
March 1928	107
September 1928	15.5
April 1929	72.8
October 1929	7.84
April 1930	97.9
October 1930	8.56
April 1931	107
October 1931	7.40
April 1932	158
October 1932	9.63
April 1933	169
October 1933	92.9
April 1934	186
October 1934	47.1
April 1935	128
October 1935	49.6
April 1936	119
October 1936	48.5
April 1937	113
October 1937	75.8
April 1938	168
November 1938	96.8
May 1939	186
November 1939	61.1
May 1940	189
November 1940	29.9
May 1941	117
November 1941	33.4
May 1942	137
November 1942	51.7
May 1943	177
November 1943	40.4
May 1944	156
November 1944	40.2
May 1945	178
November 1945	47.7
May 1946	168
November 1946	117
May 1947	191
December 1947	106
June 1948	190
December 1948	77.2
June 1949	145
December 1949	117
June 1950	153
December 1950	103
June 1951	190
December 1951	91.6
June 1952	184
December 1952	64.1
June 1953	190
December 1953	126
June 1954	182
December 1954	88.2
June 1955	185
December 1955	111
June 1956	186
December 1956	133
July 1957	137
January 1958	61.4
July 1958	141
January 1959	168
July 1959	190
January 1960	110
July 1960	180
January 1961	102
July 1961	183
January 1962	127
July 1962	189
January 1963	124
July 1963	159
January 1964	64.2
July 1964	197
January 1965	117
July 1965	191
January 1966	88.4
August 1966	143
February 1967	148
August 1967	151
February 1968	166
August 1968	101
February 1969	124
August 1969	97.2
February 1970	66.5
August 1970	135
February 1971	139
August 1971	189
February 1972	175
August 1972	136
February 1973	123
August 1973	60.6
February 1974	117
August 1974	180
February 1975	133
September 1975	96.9
March 1976	158
September 1976	16.2
March 1977	106
September 1977	17.3
March 1978	191
September 1978	76.4
March 1979	113
September 1979	10.1
March 1980	109
September 1980	43.3
March 1981	186
September 1981	56.5
March 1982	165
September 1982	89.4
March 1983	137
September 1983	87.6
March 1984	169
September 1984	110
April 1985	139
October 1985	19.6
April 1986	154
October 1986	19.2
April 1987	136
October 1987	11.5
April 1988	107
October 1988	21.8
April 1989	171
October 1989	13.7
April 1990	182
October 1990	78.5
April 1991	178
October 1991	47.1
April 1992	163
October 1992	14.4
April 1993	99.8
October 1993	10.0
May 1994	143
November 1994	33.0
May 1995	172
November 1995	91.0
May 1996	194
November 1996	75.4
May 1997	162
November 1997	136
May 1998	190
November 1998	37.8
May 1999	108
November 1999	87.9
May 2000	147
November 2000	41.0
May 2001	89.9
November 2001	43.7
May 2002	157
November 2002	21.3
May 2003	110
December 2003	65.3
June 2004	154
December 2004	80.9
June 2005	107
December 2005	39.5
June 2006	189
December 2006	84.1
June 2007	190
December 2007	70.3
June 2008	184
December 2008	113
June 2009	191
December 2009	83.1
June 2010	171
December 2010	95.4
June 2011	192
December 2011	101
June 2012	194
January 2013	117
July 2013	140
January 2014	117
July 2014	143
January 2015	156
July 2015	79.1
January 2016	120
July 2016	128
January 2017	86.7
July 2017	154
January 2018	125
July 2018	133
January 2019	97.9
July 2019	71.2
January 2020	79.9
July 2020	122
January 2021	105
July 2021	151
February 2022	151
August 2022	94.6
February 2023	74.9
August 2023	31.9
February 2024	69.4
August 2024	26.5
February 2025	40.8
August 2025	20.2
February 2026	155
August 2026	47.0

The reservoir's year

Seasonal storage profile

Each calendar month's reference average, against the most recent year

1991–2020 average
Most recent 12 months

Twelve separate averages, one per calendar month. A January average describes Januaries only. Months are plotted 1–12.

View the data behind this chart

Underlying data
Period	1991–2020 average (Mm³)	Most recent 12 months (Mm³)
Jan	98.9	139
Feb	115	155
Mar	126	168
Apr	142	188
May	159	181
Jun	165	146
Jul	135	96.8
Aug	75.1	47.0
Sep	43.5	13.7
Oct	42.9	11.9
Nov	62.3	32.6
Dec	82.4	97.3

Why this page shows a volume and not a percentage

Percentage full is a division, and the denominator is missing

“Percentage full” is the figure a drought is discussed in, and it is stored volume divided by capacity. Capacity is published on several different bases — gross, usable, live, and the figure at a particular spillway or licence condition — and dividing a stored volume by the wrong one produces a percentage confidently wrong by the ratio between them, at exactly the moment the number matters most.

Hydrionis holds storage measurements for this reservoir and does not hold a compatible authoritative capacity figure for it, so percentage full is not calculated. The volume above is what was actually measured. Where you need a percentage, take the publisher’s own capacity on its own stated basis and divide it yourself — the source is linked below, and knowing which basis you used is the whole point.

Water level

Monthly mean water surface elevation

1,376 monthly values

An elevation above a datum, not a depth of water and not a distance below the crest. Levels at different reservoirs are measured against different datums and must not be read against one another; this line is comparable only with its own history. Elevation and volume are not proportional either — a metre near the bottom of a reservoir holds far less water than a metre near the top, because the surface area grows with height.

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 1,376 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 1,376 would be longer than this page and unusable with a screen reader.
Period	Keechelus Lake (m)
1912	766
1912.5	765
1913	765
1913.4166666666667	766
1913.9166666666667	765
1914.4166666666667	765
1914.9166666666667	746
1915.3333333333333	742
1915.8333333333333	743
1916.3333333333333	744
1916.8333333333333	747
1917.25	746
1917.75	752
1918.25	753
1918.75	742
1919.1666666666667	746
1919.6666666666667	751
1920.1666666666667	758
1920.6666666666667	742
1921.0833333333333	758
1921.5833333333333	756
1922.0833333333333	761
1922.5833333333333	751
1923	753
1923.5	767
1924	752
1924.5	765
1924.9166666666667	750
1925.4166666666667	767
1925.9166666666667	750
1926.4166666666667	762
1926.8333333333333	746
1927.3333333333333	760
1927.8333333333333	754
1928.3333333333333	765
1928.75	744
1929.25	753
1929.75	741
1930.25	756
1930.6666666666667	744
1931.1666666666667	753
1931.6666666666667	741
1932.1666666666667	759
1932.5833333333333	758
1933.0833333333333	764
1933.5833333333333	763
1934.0833333333333	759
1934.5	762
1935	759
1935.5	765
1936	752
1936.4166666666667	767
1936.9166666666667	750
1937.4166666666667	767
1937.9166666666667	762
1938.3333333333333	767
1938.8333333333333	756
1939.3333333333333	766
1939.8333333333333	751
1940.25	765
1940.75	744
1941.25	758
1941.75	742
1942.1666666666667	755
1942.6666666666667	749
1943.1666666666667	759
1943.6666666666667	753
1944.0833333333333	755
1944.5833333333333	757
1945.0833333333333	759
1945.5833333333333	755
1946	755
1946.5	766
1947	760
1947.5	763
1947.9166666666667	757
1948.4166666666667	767
1948.9166666666667	753
1949.4166666666667	762
1949.8333333333333	761
1950.3333333333333	755
1950.8333333333333	754
1951.3333333333333	762
1951.8333333333333	754
1952.25	759
1952.75	751
1953.25	761
1953.75	754
1954.1666666666667	757
1954.6666666666667	758
1955.1666666666667	760
1955.6666666666667	756
1956.0833333333333	754
1956.5833333333333	759
1957.0833333333333	762
1957.5833333333333	752
1958	751
1958.5	761
1959	764
1959.5	767
1959.9166666666667	762
1960.4166666666667	767
1960.9166666666667	754
1961.4166666666667	767
1961.8333333333333	756
1962.3333333333333	767
1962.8333333333333	754
1963.3333333333333	767
1963.75	741
1964.25	756
1964.75	759
1965.25	759
1965.6666666666667	755
1966.1666666666667	757
1966.6666666666667	754
1967.1666666666667	763
1967.5833333333333	763
1968.0833333333333	764
1968.5833333333333	757
1969.0833333333333	760
1969.5	764
1970	749
1970.5	766
1971	756
1971.4166666666667	766
1971.9166666666667	761
1972.4166666666667	766
1972.9166666666667	753
1973.3333333333333	763
1973.8333333333333	744
1974.3333333333333	762
1974.8333333333333	756
1975.25	759
1975.75	755
1976.25	761
1976.75	742
1977.1666666666667	757
1977.6666666666667	743
1978.1666666666667	767
1978.6666666666667	753
1979.0833333333333	755
1979.5833333333333	742
1980.0833333333333	755
1980.5833333333333	753
1981	761
1981.5	764
1982	754
1982.5	766
1982.9166666666667	753
1983.4166666666667	767
1983.9166666666667	760
1984.4166666666667	767
1984.8333333333333	755
1985.3333333333333	764
1985.8333333333333	752
1986.3333333333333	763
1986.75	743
1987.25	761
1987.75	741
1988.25	757
1988.75	743
1989.1666666666667	761
1989.6666666666667	747
1990.1666666666667	763
1990.6666666666667	752
1991.0833333333333	763
1991.5833333333333	757
1992.0833333333333	760
1992.5833333333333	752
1993	748
1993.5	767
1994	747
1994.5	763
1994.9166666666667	750
1995.4166666666667	763
1995.9166666666667	762
1996.4166666666667	767
1996.8333333333333	753
1997.3333333333333	764
1997.8333333333333	761
1998.3333333333333	767
1998.75	744
1999.25	756
1999.75	752
2000.25	758
2000.6666666666667	745
2001.1666666666667	745
2001.6666666666667	742
2002.1666666666667	758
2002.5833333333333	750
2003.0833333333333	750
2003.5833333333333	743
2004.0833333333333	754
2004.5	757
2005	757
2005.5	753
2006	751
2006.4166666666667	767
2006.9166666666667	754
2007.4166666666667	767
2007.9166666666667	752
2008.3333333333333	758
2008.8333333333333	755
2009.3333333333333	766
2009.8333333333333	752
2010.25	760
2010.75	750
2011.25	765
2011.75	755
2012.1666666666667	762
2012.6666666666667	752
2013.1666666666667	761
2013.6666666666667	749
2014.0833333333333	760
2014.5833333333333	752
2015.0833333333333	767
2015.5833333333333	747
2016	759
2016.5	760
2017	755
2017.5	763
2017.9166666666667	758
2018.4166666666667	766
2018.9166666666667	753
2019.4166666666667	758
2019.8333333333333	746
2020.3333333333333	765
2020.8333333333333	752
2021.3333333333333	763
2021.75	749
2022.25	766
2022.75	750
2023.25	754
2023.6666666666667	743
2024.1666666666667	754
2024.6666666666667	742
2025.1666666666667	750
2025.5833333333333	743
2026.0833333333333	763
2026.5833333333333	748

Rate and persistence

+2.23 Mm³

Mean change per month over 12 months

15 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

Keechelus Lake

Gauge location

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 Bureau of Reclamation — Reservoir operations and Colorado River data · US Government work — public domain
How the values came to exist	Measured
Period held	1906–2026
Completeness	99.7% 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.
Continuity	100% of the months between 1906 and 2026 are held. Monthly means of the publisher's own daily record.
Last read from the publisher	2026-09-01
Redistribution	Permitted by the upstream licences
Commercial reuse	Permitted by the upstream licences. No Hydrionis access tier can widen this.
Methodology	How this was produced

Use this data

Machine-readable JSON /api/v1/observations/by-subject/reservoir-usbr-7187.json
How to cite this, and who you must credit
How these figures were produced
Request this at a different scale, format or geography

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), Keechelus Lake reservoir records, accessed 2026-09-02, hydrionis.com/reservoirs/reservoir-usbr-7187/

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 Keechelus Lake 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

1,448 monthly observations 1906–2026 Mm³

Spatially aggregatedHigh confidenceAugust 2026

Source: USBR — Reservoir operations and Colorado River data, RISE catalogue item 131246. Licence: Open.

Method: Monthly mean of the daily values published by the Bureau of Reclamation in acre-feet, converted to Mm³. Months with fewer than 20 days of record are not published rather than averaged from a partial month.

Stored as a volume and not as a share of capacity: the operator publishes what is in the reservoir but not what it holds when full, so a percentage cannot be computed without inventing the denominator.

Retrieved 1 September 2026.

Monthly mean of the daily values published by the Bureau of Reclamation in acre-feet, converted to Mm³. Months with fewer than 20 days of record are not published rather than averaged from a partial month.