Wolford Mtn Reservoir, CO — storage

Storage now, against this reservoir's own record

26.10 Mm³

Stored, September 2026

0th

Percentile among 22 Seps on record

Storage in September 2026 was lower than almost every other Sep on record, ranked against 22 other Seps held for this reservoir. It is the lowest in the held record for this month.

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, 1998–2026

Monthly mean storage

261 monthly values, 1998 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 261 periods, evenly spaced across the record. Every value is in the download and the API; a table of all 261 would be longer than this page and unusable with a screen reader.
Period	Wolford Mtn Reservoir Nr Kremmling, CO (Mm³)
October 1998	62.0
December 1998	60.2
January 1999	59.6
February 1999	59.5
March 1999	59.7
April 1999	60.4
June 1999	82.2
July 1999	81.4
August 1999	80.7
September 1999	75.7
October 2004	38.1
November 2004	35.9
December 2004	35.4
January 2005	35.2
February 2005	34.9
March 2005	34.6
April 2005	36.4
May 2005	49.0
July 2005	74.2
August 2005	72.4
September 2005	69.8
October 2005	68.6
November 2005	67.9
December 2005	67.4
January 2006	67.0
February 2006	66.8
March 2006	66.8
April 2006	71.2
May 2006	83.1
July 2006	81.0
August 2006	75.0
September 2006	66.4
October 2006	63.6
November 2006	62.8
December 2006	61.8
January 2007	61.0
February 2007	60.1
March 2007	61.0
April 2007	67.0
May 2007	79.7
July 2007	80.5
August 2007	77.5
September 2007	69.5
October 2008	65.7
November 2008	64.9
December 2008	64.3
January 2009	63.8
February 2009	63.5
March 2009	63.4
April 2009	65.4
May 2009	80.7
June 2009	82.1
August 2009	77.8
September 2009	69.3
October 2009	66.7
November 2009	65.9
December 2009	65.1
January 2010	64.2
February 2010	63.7
March 2010	63.7
April 2010	65.6
May 2010	76.0
June 2010	82.3
August 2010	78.4
September 2010	71.9
October 2010	67.9
November 2010	67.4
December 2010	67.0
January 2011	66.8
February 2011	66.6
March 2011	67.0
April 2011	71.4
May 2011	76.1
June 2011	83.5
August 2011	80.9
September 2011	74.5
October 2011	71.5
November 2011	72.0
December 2011	72.1
January 2012	71.8
February 2012	71.7
March 2012	73.4
April 2012	80.0
May 2012	81.8
June 2012	80.3
July 2012	76.0
September 2012	48.3
October 2012	34.7
November 2012	31.5
December 2012	30.8
January 2013	30.3
February 2013	29.9
March 2013	29.7
April 2013	31.0
May 2013	46.4
June 2013	63.8
July 2013	63.7
September 2013	55.6
October 2013	54.7
November 2013	54.4
December 2013	54.2
January 2014	54.1
February 2014	53.9
March 2014	53.5
April 2014	53.8
May 2014	71.7
June 2014	81.3
July 2014	69.4
August 2014	61.1
October 2014	57.7
November 2014	57.3
December 2014	57.2
January 2015	56.8
February 2015	56.4
March 2015	56.2
April 2015	58.8
May 2015	64.0
June 2015	60.9
July 2015	63.0
August 2015	60.1
October 2015	55.9
November 2015	55.0
December 2015	54.2
January 2016	53.2
February 2016	52.2
March 2016	51.8
April 2016	53.7
May 2016	70.4
June 2016	80.5
July 2016	80.0
August 2016	73.0
October 2016	65.0
November 2016	64.1
December 2016	63.3
January 2017	62.9
February 2017	62.5
March 2017	62.7
April 2017	68.5
May 2017	80.1
June 2017	81.5
July 2017	81.3
August 2017	78.9
September 2017	71.7
November 2017	68.9
December 2017	68.2
January 2018	67.6
February 2018	67.1
March 2018	66.8
April 2018	66.9
May 2018	78.6
June 2018	81.7
July 2018	76.5
August 2018	58.3
September 2018	47.4
November 2018	44.1
December 2018	43.2
January 2019	42.4
February 2019	41.8
March 2019	41.3
April 2019	42.1
May 2019	58.3
June 2019	80.6
July 2019	81.9
August 2019	78.8
September 2019	69.6
October 2019	65.2
December 2019	63.4
January 2020	63.0
February 2020	62.6
March 2020	62.6
April 2020	63.5
May 2020	79.5
June 2020	81.3
July 2020	80.7
August 2020	75.5
September 2020	72.4
October 2020	70.0
December 2020	67.6
January 2021	66.5
February 2021	65.8
March 2021	65.3
April 2021	65.0
May 2021	72.6
June 2021	80.0
July 2021	78.5
August 2021	75.2
September 2021	58.7
October 2021	43.0
December 2021	38.8
January 2022	38.2
February 2022	37.6
March 2022	37.0
April 2022	37.4
May 2022	50.4
June 2022	65.7
July 2022	68.5
August 2022	66.8
September 2022	60.2
October 2022	52.0
November 2022	50.9
January 2023	49.4
February 2023	48.8
March 2023	48.2
April 2023	48.0
May 2023	64.0
June 2023	80.7
July 2023	81.4
August 2023	77.5
September 2023	71.3
October 2023	69.0
November 2023	67.5
January 2024	66.1
February 2024	65.6
March 2024	65.2
April 2024	66.5
May 2024	77.6
June 2024	80.9
July 2024	80.9
August 2024	74.6
September 2024	69.8
October 2024	67.9
November 2024	67.1
January 2025	66.1
February 2025	65.7
March 2025	65.6
April 2025	66.6
May 2025	77.4
June 2025	81.8
July 2025	78.8
August 2025	72.8
September 2025	60.1
October 2025	56.4
November 2025	54.9
December 2025	53.9
February 2026	52.1
March 2026	51.9
June 2026	54.3
July 2026	47.1
August 2026	32.4
September 2026	26.1

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

4 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

Wolford Mtn Reservoir Nr Kremmling, CO

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	1998–2026
Completeness	75.0% 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	75% of the months between 1998 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-usgs-09041395.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), Wolford Mtn Reservoir Nr Kremmling, CO reservoir records, accessed 2026-10-05, hydrionis.com/reservoirs/reservoir-usgs-09041395/

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 Wolford Mtn Reservoir Nr Kremmling, CO 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

261 monthly observations 1998–2026 Mm³

Spatially aggregatedHigh confidenceSeptember 2026

Source: USGS — National Water Information System, 09041395. 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.