Keechelus Lake — storage

Storage now, against this reservoir's own record

15.37 Mm³

Stored, September 2026

16th

Percentile among 121 Seps on record

-64.7%

Against the Sep 1991–2020 average

+12.5%

Change over the 12 months to 2026-09

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

Storage, 1906–2026

Monthly mean storage

1,449 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 1,449 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 1,449 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
August 1910	18.6
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
March 1919	37.3
September 1919	62.9
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
October 1927	52.7
April 1928	129
October 1928	22.6
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
May 1936	179
November 1936	47.3
May 1937	150
November 1937	98.0
May 1938	188
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
December 1944	58.9
June 1945	183
December 1945	63.8
June 1946	191
December 1946	124
June 1947	189
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
July 1953	185
January 1954	125
July 1954	191
January 1955	100
July 1955	189
January 1956	88.9
July 1956	186
January 1957	142
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
February 1962	123
August 1962	136
February 1963	142
August 1963	83.5
February 1964	73.7
August 1964	183
February 1965	133
August 1965	157
February 1966	97.7
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
March 1971	154
September 1971	139
March 1972	184
September 1972	74.8
March 1973	133
September 1973	12.3
March 1974	130
September 1974	141
March 1975	119
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
October 1979	9.78
April 1980	134
October 1980	24.9
April 1981	194
October 1981	45.2
April 1982	183
October 1982	55.8
April 1983	160
October 1983	84.1
April 1984	182
October 1984	78.8
April 1985	139
October 1985	19.6
April 1986	154
October 1986	19.2
April 1987	136
October 1987	11.5
May 1988	145
November 1988	53.2
May 1989	186
November 1989	35.0
May 1990	192
November 1990	141
May 1991	176
November 1991	55.7
May 1992	147
November 1992	27.1
May 1993	151
November 1993	13.4
May 1994	143
November 1994	33.0
May 1995	172
November 1995	91.0
May 1996	194
December 1996	97.2
June 1997	188
December 1997	148
June 1998	185
December 1998	62.0
June 1999	154
December 1999	110
June 2000	170
December 2000	35.1
June 2001	111
December 2001	65.8
June 2002	170
December 2002	22.1
June 2003	92.9
December 2003	65.3
June 2004	154
December 2004	80.9
July 2005	75.0
January 2006	63.9
July 2006	141
January 2007	98.9
July 2007	143
January 2008	75.2
July 2008	174
January 2009	146
July 2009	147
January 2010	94.3
July 2010	141
January 2011	128
July 2011	179
January 2012	120
July 2012	179
January 2013	117
July 2013	140
February 2014	127
August 2014	73.0
February 2015	188
August 2015	41.4
February 2016	141
August 2016	64.1
February 2017	86.8
August 2017	85.1
February 2018	154
August 2018	69.4
February 2019	109
August 2019	34.8
February 2020	130
August 2020	64.9
February 2021	116
August 2021	81.7
February 2022	151
September 2022	63.9
March 2023	78.1
September 2023	19.1
March 2024	82.6
September 2024	14.4
March 2025	57.9
September 2025	13.7
March 2026	168
September 2026	15.4

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	46.9
Sep	43.5	15.4
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

1,377 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 1,377 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 1,377 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
1928.8333333333333	746
1929.25	753
1929.75	741
1930.25	756
1930.75	741
1931.1666666666667	753
1931.6666666666667	741
1932.1666666666667	759
1932.6666666666667	743
1933.0833333333333	764
1933.5833333333333	763
1934.0833333333333	759
1934.5833333333333	755
1935	759
1935.5	765
1936	752
1936.5	763
1936.9166666666667	750
1937.4166666666667	767
1937.9166666666667	762
1938.4166666666667	767
1938.8333333333333	756
1939.3333333333333	766
1939.8333333333333	751
1940.3333333333333	767
1940.75	744
1941.25	758
1941.75	742
1942.25	758
1942.6666666666667	749
1943.1666666666667	759
1943.6666666666667	753
1944.1666666666667	756
1944.5833333333333	757
1945.0833333333333	759
1945.5833333333333	755
1946.0833333333333	756
1946.5833333333333	763
1947	760
1947.5	763
1948	758
1948.5	766
1948.9166666666667	753
1949.4166666666667	762
1949.9166666666667	759
1950.4166666666667	763
1950.8333333333333	754
1951.3333333333333	762
1951.8333333333333	754
1952.3333333333333	763
1952.75	751
1953.25	761
1953.75	754
1954.25	757
1954.6666666666667	758
1955.1666666666667	760
1955.6666666666667	756
1956.1666666666667	753
1956.5833333333333	759
1957.0833333333333	762
1957.5833333333333	752
1958.0833333333333	753
1958.5	761
1959	764
1959.5	767
1960	758
1960.4166666666667	767
1960.9166666666667	754
1961.4166666666667	767
1961.9166666666667	758
1962.4166666666667	767
1962.8333333333333	754
1963.3333333333333	767
1963.8333333333333	744
1964.3333333333333	757
1964.75	759
1965.25	759
1965.75	748
1966.25	761
1966.6666666666667	754
1967.1666666666667	763
1967.6666666666667	755
1968.1666666666667	766
1968.5833333333333	757
1969.0833333333333	760
1969.5833333333333	756
1970.0833333333333	751
1970.5	766
1971	756
1971.5	767
1972	763
1972.4166666666667	766
1972.9166666666667	753
1973.4166666666667	761
1973.9166666666667	748
1974.3333333333333	762
1974.8333333333333	756
1975.3333333333333	762
1975.8333333333333	759
1976.25	761
1976.75	742
1977.25	760
1977.75	744
1978.25	766
1978.6666666666667	753
1979.1666666666667	758
1979.6666666666667	741
1980.1666666666667	758
1980.5833333333333	753
1981.0833333333333	763
1981.5833333333333	756
1982.0833333333333	759
1982.5	766
1983	756
1983.5	764
1984	762
1984.4166666666667	767
1984.9166666666667	757
1985.4166666666667	767
1985.9166666666667	753
1986.3333333333333	763
1986.8333333333333	747
1987.3333333333333	765
1987.8333333333333	742
1988.25	757
1988.75	743
1989.25	765
1989.75	742
1990.1666666666667	763
1990.6666666666667	752
1991.1666666666667	765
1991.6666666666667	749
1992.0833333333333	760
1992.5833333333333	752
1993.0833333333333	750
1993.5833333333333	763
1994.0833333333333	749
1994.5	763
1995	754
1995.5	755
1996	763
1996.4166666666667	767
1996.9166666666667	756
1997.4166666666667	767
1997.9166666666667	762
1998.3333333333333	767
1998.8333333333333	746
1999.3333333333333	758
1999.8333333333333	755
2000.25	758
2000.75	747
2001.25	748
2001.75	742
2002.1666666666667	758
2002.6666666666667	745
2003.1666666666667	753
2003.6666666666667	742
2004.0833333333333	754
2004.5833333333333	748
2005.0833333333333	760
2005.5833333333333	746
2006	751
2006.5	761
2007	756
2007.5	762
2007.9166666666667	752
2008.4166666666667	766
2008.9166666666667	758
2009.4166666666667	767
2009.8333333333333	752
2010.3333333333333	762
2010.8333333333333	753
2011.3333333333333	765
2011.8333333333333	756
2012.25	763
2012.75	752
2013.25	765
2013.75	751
2014.1666666666667	763
2014.6666666666667	749
2015.1666666666667	767
2015.6666666666667	743
2016.0833333333333	762
2016.5833333333333	751
2017.0833333333333	755
2017.5833333333333	754
2018	760
2018.5	761
2019	756
2019.5	752
2019.9166666666667	748
2020.4166666666667	764
2020.9166666666667	754
2021.4166666666667	766
2021.8333333333333	754
2022.3333333333333	766
2022.8333333333333	751
2023.3333333333333	759
2023.75	742
2024.25	757
2024.75	741
2025.25	756
2025.6666666666667	742
2026.1666666666667	764
2026.6666666666667	742

Rate and persistence

+0.14 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	99.8% 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	2026-10-01
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 2026-10-05, 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

1,449 monthly observations 1906–2026 Mm³

Spatially aggregatedHigh confidenceSeptember 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 October 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.