Lake Avalon — storage

Storage now, against this reservoir's own record

3.39 Mm³

Stored, March 2017

50th

Percentile among 51 Mars on record

+11.8%

Against the Mar 1991–2020 average

-7.9%

Change over the 12 months to 2017-03

Storage in March 2017 was around the middle of the Mar record, ranked against 51 other Mars held for this reservoir.

Storage, 1965–2017

Monthly mean storage

602 monthly values, 1965 to 2017

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 602 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 602 would be longer than this page and unusable with a screen reader.
Period	Lake Avalon Nr Carlsbad N Mex (Mm³)
October 1965	0.184
January 1966	1.96
March 1966	2.30
June 1966	1.29
August 1966	2.92
November 1966	1.87
January 1967	5.10
April 1967	1.43
June 1967	1.66
September 1967	1.78
December 1967	3.22
March 1968	3.66
May 1968	1.66
August 1968	1.66
October 1969	3.76
January 1970	6.13
March 1970	5.78
June 1970	2.25
August 1970	1.04
November 1970	2.52
January 1971	4.37
April 1971	1.44
June 1971	1.22
September 1971	1.49
November 1971	1.51
February 1972	3.15
April 1972	0.999
July 1972	0.842
September 1972	5.49
December 1972	4.89
February 1973	6.04
May 1973	5.88
July 1973	1.74
October 1973	1.05
December 1973	2.37
March 1974	3.18
June 1974	1.08
August 1974	1.07
November 1974	6.33
January 1975	6.25
April 1975	2.35
June 1975	1.29
September 1975	1.27
November 1975	2.22
February 1976	3.50
April 1976	1.88
July 1976	0.901
September 1976	3.48
December 1976	4.01
February 1977	4.71
May 1977	1.92
July 1977	2.01
October 1977	1.50
December 1977	2.45
March 1978	3.03
May 1978	2.44
August 1978	2.16
October 1978	5.76
January 1979	6.02
March 1979	6.07
June 1979	5.35
August 1979	1.75
February 1980	4.59
April 1980	1.58
July 1980	1.48
September 1980	2.73
December 1980	4.38
February 1981	5.20
May 1981	1.65
August 1981	1.70
October 1981	1.25
January 1982	2.41
March 1982	2.52
June 1982	1.35
August 1982	1.18
November 1982	0.858
January 1983	3.10
April 1983	1.01
June 1983	1.05
September 1983	1.20
November 1983	2.03
February 1984	4.11
April 1984	1.86
July 1984	1.28
September 1984	1.43
December 1984	4.01
February 1985	5.48
May 1985	1.68
July 1985	1.38
October 1985	0.930
December 1985	3.74
March 1986	2.07
May 1986	2.01
August 1986	1.84
October 1986	3.16
January 1987	5.87
March 1987	5.75
June 1987	5.94
August 1987	2.08
November 1987	1.92
January 1988	4.67
April 1988	1.27
June 1988	1.38
September 1988	2.16
December 1988	0.128
February 1989	0.687
May 1989	1.40
July 1989	1.25
October 1989	1.21
December 1989	1.70
March 1990	2.77
May 1990	1.52
August 1990	1.13
October 1990	1.10
January 1991	2.34
March 1991	2.76
June 1991	1.18
August 1991	1.17
November 1991	2.05
January 1992	2.12
April 1992	1.24
June 1992	5.43
September 1992	1.32
November 1992	1.14
February 1993	2.51
April 1993	1.28
July 1993	1.52
September 1993	1.37
December 1993	1.22
February 1994	2.10
May 1994	1.42
July 1994	1.53
October 1994	1.98
December 1994	0
March 1995	2.13
May 1995	1.40
August 1995	1.24
November 1995	0.019
January 1996	0
April 1996	1.34
June 1996	1.09
September 1996	3.92
November 1996	0.979
February 1997	3.26
April 1997	1.26
July 1997	1.57
September 1997	1.16
December 1997	2.14
February 1998	3.86
May 1998	1.67
July 1998	1.51
October 1998	1.86
December 1998	2.63
March 1999	3.77
May 1999	1.22
August 1999	1.38
October 1999	1.72
January 2000	0.107
March 2000	1.62
June 2000	1.49
August 2000	1.52
November 2000	2.05
January 2001	3.48
April 2001	1.46
June 2001	1.35
September 2001	1.57
November 2001	1.79
February 2002	3.19
April 2002	2.23
July 2002	2.89
September 2002	2.25
December 2002	1.52
March 2003	0.715
May 2003	1.58
August 2003	1.94
October 2003	1.68
January 2004	2.50
March 2004	3.71
June 2004	1.78
August 2004	2.90
November 2004	2.32
January 2005	2.20
April 2005	1.61
June 2005	1.60
September 2005	1.71
November 2005	2.09
February 2006	3.11
April 2006	1.52
July 2006	1.48
September 2006	2.13
December 2006	1.35
February 2007	3.01
May 2007	1.68
July 2007	1.62
October 2007	1.48
December 2007	1.97
March 2008	3.22
May 2008	1.46
August 2008	1.58
October 2008	1.69
January 2009	3.02
March 2009	3.31
June 2009	1.58
August 2009	1.78
November 2009	1.49
February 2010	3.68
April 2010	2.01
July 2010	2.52
September 2010	1.96
December 2010	1.85
February 2011	3.17
May 2011	1.76
July 2011	1.70
October 2011	1.70
December 2011	2.42
March 2012	3.51
May 2012	1.77
August 2012	1.85
October 2012	2.05
January 2013	3.33
March 2013	3.86
June 2013	1.78
August 2013	1.98
November 2013	1.39
January 2014	3.10
April 2014	2.59
June 2014	1.90
September 2014	3.68
November 2014	1.89
February 2015	4.56
April 2015	1.66
July 2015	3.60
September 2015	6.28
December 2015	2.73
February 2016	5.75
May 2016	2.40
July 2016	2.10
October 2016	1.58
December 2016	2.43
March 2017	3.39

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	2.51	3.22
Feb	3.10	3.75
Mar	3.03	3.39
Apr	1.76	2.46
May	1.69	2.40
Jun	1.71	2.30
Jul	1.88	2.10
Aug	1.89	2.36
Sep	2.24	3.76
Oct	1.95	1.58
Nov	1.57	1.50
Dec	1.86	2.43

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.

Rate and persistence

-0.02 Mm³

Mean drawdown per month over 12 months

0 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

Lake Avalon Nr Carlsbad N Mex

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 Geological Survey — National Water Information System · US Government work — public domain
How the values came to exist	Measured
Period held	1965–2017
Completeness	94.7% 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	95% of the months between 1965 and 2017 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-usgs-08403800.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), Lake Avalon Nr Carlsbad N Mex reservoir records, accessed 2026-10-05, hydrionis.com/reservoirs/reservoir-usgs-08403800/

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 Lake Avalon Nr Carlsbad N Mex 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

602 monthly observations 1965–2017 Mm³

Spatially aggregatedHigh confidenceMarch 2017

Source: USGS — National Water Information System, 08403800. 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.