Echo Reservoir, UT — storage

Storage now, against this reservoir's own record

14.84 Mm³

Stored, September 1990

24th

Percentile among 60 Seps on record

-38.5%

Change over the 12 months to 1990-09

Storage in September 1990 was lower than most Seps on record, ranked against 60 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, 1930–1990

Monthly mean storage

719 monthly values, 1930 to 1990

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 719 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 719 would be longer than this page and unusable with a screen reader.
Period	Echo Reservoir At Echo, UT (Mm³)
October 1930	4.58
January 1931	7.72
April 1931	11.6
July 1931	5.93
October 1931	0
January 1932	0.869
April 1932	28.9
July 1932	70.0
October 1932	20.7
January 1933	22.6
April 1933	39.7
July 1933	74.2
October 1933	14.2
January 1934	22.0
April 1934	44.6
July 1934	11.2
October 1934	0
January 1935	11.1
April 1935	40.5
July 1935	71.6
October 1935	3.23
January 1936	1.18
April 1936	30.5
July 1936	79.7
October 1936	39.4
January 1937	39.1
April 1937	66.3
July 1937	80.3
October 1937	36.2
January 1938	39.0
April 1938	73.6
July 1938	79.9
October 1938	21.2
January 1939	22.6
April 1939	60.7
July 1939	54.1
October 1939	2.00
January 1940	3.61
April 1940	32.1
July 1940	36.7
October 1940	3.07
January 1941	3.70
April 1941	29.1
July 1941	70.3
October 1941	20.3
January 1942	21.5
April 1942	54.1
July 1942	77.2
October 1942	20.0
January 1943	21.1
April 1943	56.4
July 1943	80.0
October 1943	25.1
January 1944	24.5
April 1944	49.4
July 1944	74.6
October 1944	0.636
January 1945	6.60
April 1945	36.3
July 1945	76.2
October 1945	40.9
January 1946	51.0
April 1946	80.4
July 1946	73.1
October 1946	22.8
January 1947	43.9
April 1947	76.5
July 1947	72.6
October 1947	26.6
January 1948	30.0
April 1948	60.2
July 1948	72.0
October 1948	9.95
January 1949	15.6
April 1949	28.8
July 1949	78.1
October 1949	25.9
January 1950	30.2
April 1950	68.7
July 1950	88.2
October 1950	48.4
January 1951	54.4
April 1951	64.5
July 1951	81.5
October 1951	47.4
January 1952	47.4
April 1952	25.3
July 1952	85.5
October 1952	48.2
January 1953	48.5
April 1953	65.7
July 1953	76.7
October 1953	16.7
January 1954	35.1
April 1954	52.6
July 1954	44.2
November 1954	1.33
February 1955	20.4
May 1955	67.0
August 1955	30.6
November 1955	10.1
February 1956	40.5
May 1956	83.8
August 1956	33.9
November 1956	11.1
February 1957	24.2
May 1957	67.2
August 1957	50.4
November 1957	36.4
February 1958	45.7
May 1958	72.5
August 1958	21.2
November 1958	11.6
February 1959	30.9
May 1959	57.2
August 1959	24.2
November 1959	16.3
February 1960	31.2
May 1960	66.2
August 1960	22.1
December 1960	19.9
March 1961	36.5
June 1961	29.0
September 1961	0.853
December 1961	13.0
March 1962	33.5
June 1962	73.0
September 1962	20.3
December 1962	27.7
March 1963	51.1
June 1963	77.2
September 1963	16.5
December 1963	35.2
March 1964	50.6
June 1964	91.9
September 1964	29.3
December 1964	47.1
March 1965	65.7
June 1965	90.2
September 1965	65.2
December 1965	77.4
March 1966	77.4
June 1966	84.3
September 1966	21.1
December 1966	44.8
March 1967	63.2
June 1967	90.9
September 1967	36.2
December 1967	24.9
March 1968	49.6
June 1968	89.5
September 1968	37.7
December 1968	68.4
March 1969	42.4
June 1969	89.9
September 1969	36.9
December 1969	48.0
March 1970	76.4
June 1970	91.1
September 1970	41.5
December 1970	64.3
March 1971	76.0
June 1971	90.7
September 1971	46.8
December 1971	59.9
March 1972	70.3
June 1972	90.7
September 1972	37.7
December 1972	61.3
March 1973	61.4
June 1973	90.6
September 1973	51.6
December 1973	52.7
March 1974	64.8
June 1974	90.0
September 1974	36.4
December 1974	61.9
March 1975	81.1
June 1975	77.7
September 1975	59.2
December 1975	52.8
March 1976	59.2
June 1976	81.2
September 1976	20.3
December 1976	44.1
March 1977	60.6
June 1977	65.7
September 1977	24.4
December 1977	46.3
March 1978	58.7
June 1978	90.5
September 1978	42.8
December 1978	64.7
March 1979	79.4
June 1979	87.1
September 1979	21.1
December 1979	31.2
March 1980	67.0
June 1980	90.0
September 1980	44.2
December 1980	62.0
March 1981	73.7
June 1981	89.1
September 1981	22.7
December 1981	51.0
March 1982	66.2
June 1982	88.7
September 1982	53.1
December 1982	58.3
March 1983	63.3
June 1983	91.7
September 1983	65.7
December 1983	55.3
March 1984	37.9
June 1984	89.1
September 1984	59.2
December 1984	73.5
March 1985	55.1
June 1985	90.2
September 1985	32.9
December 1985	70.6
March 1986	39.1
June 1986	82.6
September 1986	60.3
December 1986	76.9
March 1987	81.0
June 1987	82.8
September 1987	27.5
December 1987	47.4
March 1988	73.9
June 1988	77.7
September 1988	9.83
December 1988	48.6
March 1989	67.5
June 1989	81.0
September 1989	24.1
December 1989	32.1
March 1990	65.5
June 1990	76.7
September 1990	14.8

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

-0.77 Mm³

Mean drawdown per month over 12 months

2 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

Echo Reservoir At Echo, UT

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	1930–1990
Completeness	98.2% 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	98% of the months between 1930 and 1990 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-10131500.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), Echo Reservoir At Echo, UT reservoir records, accessed 2026-10-05, hydrionis.com/reservoirs/reservoir-usgs-10131500/

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 Echo Reservoir At Echo, UT 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

719 monthly observations 1930–1990 Mm³

Spatially aggregatedHigh confidenceSeptember 1990

Source: USGS — National Water Information System, 10131500. 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.