Cottage Grove Lake, OR — storage

Storage now, against this reservoir's own record

21.13 Mm³

Stored, September 1974

48th

Percentile among 32 Seps on record

-27.9%

Change over the 12 months to 1974-09

Storage in September 1974 was around the middle of the Sep record, ranked against 32 other Seps held for this reservoir.

Storage, 1942–1974

Monthly mean storage

384 monthly values, 1942 to 1974

Monthly means of the publisher's daily record. Volume, not percentage of capacity: without a capacity whose definition is stated, fullness cannot be computed.

View the data behind this chart

Underlying data
Period	Cottage Grove Lake Nr Cottage Grove, OR (Mm³)
October 1942	0.0002
November 1942	2.91
December 1942	11.2
January 1943	9.14
February 1943	9.37
March 1943	19.2
April 1943	34.4
May 1943	41.1
June 1943	41.2
July 1943	40.8
August 1943	39.4
September 1943	34.6
October 1943	15.5
November 1943	4.09
December 1943	1.09
January 1944	1.01
February 1944	5.11
March 1944	17.7
April 1944	32.0
May 1944	40.9
June 1944	41.0
July 1944	40.8
August 1944	40.1
September 1944	30.9
October 1944	11.6
November 1944	3.84
December 1944	3.70
January 1945	3.90
February 1945	10.1
March 1945	22.7
April 1945	34.4
May 1945	41.0
June 1945	41.1
July 1945	40.6
August 1945	39.2
September 1945	23.6
October 1945	8.17
November 1945	4.65
December 1945	5.52
January 1946	4.35
February 1946	9.33
March 1946	21.8
April 1946	33.7
May 1946	39.5
June 1946	40.9
July 1946	40.4
August 1946	39.0
September 1946	33.5
October 1946	8.94
November 1946	4.00
December 1946	4.16
January 1947	3.92
February 1947	9.58
March 1947	25.0
April 1947	36.9
May 1947	40.9
June 1947	40.4
July 1947	39.5
August 1947	39.3
September 1947	38.3
October 1947	25.5
November 1947	4.36
December 1947	4.21
January 1948	5.76
February 1948	10.4
March 1948	21.9
April 1948	34.5
May 1948	41.6
June 1948	40.6
July 1948	40.4
August 1948	38.7
September 1948	14.2
October 1948	5.56
November 1948	3.96
December 1948	5.79
January 1949	4.24
February 1949	5.82
March 1949	21.7
April 1949	32.7
May 1949	41.2
June 1949	40.7
July 1949	38.9
August 1949	36.1
September 1949	31.0
October 1949	8.06
November 1949	3.60
December 1949	4.06
January 1950	5.87
February 1950	7.47
March 1950	22.3
April 1950	34.6
May 1950	40.9
June 1950	40.7
July 1950	39.8
August 1950	37.1
September 1950	28.0
October 1950	11.6
November 1950	4.91
December 1950	3.99
January 1951	5.35
February 1951	9.54
March 1951	21.8
April 1951	31.4
May 1951	36.5
June 1951	37.1
July 1951	34.7
August 1951	29.2
September 1951	20.8
October 1951	8.49
November 1951	3.91
December 1951	4.05
January 1952	3.93
February 1952	9.15
March 1952	21.7
April 1952	34.1
May 1952	39.4
June 1952	39.5
July 1952	39.2
August 1952	33.8
September 1952	23.4
October 1952	10.4
November 1952	3.66
December 1952	3.82
January 1953	8.10
February 1953	9.35
March 1953	21.8
April 1953	34.1
May 1953	39.4
June 1953	39.5
July 1953	39.3
August 1953	34.5
September 1953	23.4
October 1953	8.64
November 1953	6.97
December 1953	4.96
January 1954	5.74
February 1954	8.43
March 1954	17.9
April 1954	28.2
May 1954	32.2
June 1954	32.5
July 1954	32.0
August 1954	29.8
September 1954	22.4
October 1954	7.36
November 1954	3.58
December 1954	3.68
January 1955	3.69
February 1955	7.90
March 1955	19.5
April 1955	28.6
May 1955	37.9
June 1955	39.3
July 1955	38.6
August 1955	32.5
September 1955	8.96
October 1955	6.26
November 1955	6.25
December 1955	17.3
January 1956	6.09
February 1956	10.4
March 1956	18.4
April 1956	28.6
May 1956	37.8
June 1956	39.6
July 1956	39.1
August 1956	36.2
September 1956	21.3
October 1956	8.02
November 1956	3.99
December 1956	4.52
January 1957	3.64
February 1957	12.5
March 1957	24.4
April 1957	29.3
May 1957	35.3
June 1957	39.6
July 1957	38.4
August 1957	20.8
September 1957	6.93
October 1957	6.47
November 1957	4.50
December 1957	11.5
January 1958	4.62
February 1958	11.4
March 1958	18.2
April 1958	28.5
May 1958	35.1
June 1958	39.7
July 1958	39.4
August 1958	34.1
September 1958	17.9
October 1958	7.18
November 1958	4.60
December 1958	3.96
January 1959	6.19
February 1959	9.95
March 1959	18.7
April 1959	31.5
May 1959	37.7
June 1959	40.0
July 1959	38.7
August 1959	25.0
September 1959	8.92
October 1959	6.88
November 1959	3.55
December 1959	3.65
January 1960	4.25
February 1960	12.6
March 1960	21.4
April 1960	29.4
May 1960	37.6
June 1960	39.9
July 1960	38.3
August 1960	33.7
September 1960	23.7
October 1960	8.76
November 1960	6.98
December 1960	3.74
January 1961	3.72
February 1961	18.2
March 1961	18.8
April 1961	27.6
May 1961	37.3
June 1961	39.6
July 1961	38.0
August 1961	30.8
September 1961	17.1
October 1961	10.8
November 1961	7.59
December 1961	3.56
January 1962	3.57
February 1962	8.61
March 1962	19.5
April 1962	28.3
May 1962	37.9
June 1962	39.5
July 1962	38.1
August 1962	35.6
September 1962	26.1
October 1962	12.2
November 1962	5.47
December 1962	8.09
January 1963	3.63
February 1963	10.4
March 1963	21.1
April 1963	29.8
May 1963	39.0
June 1963	39.7
July 1963	39.7
August 1963	38.0
September 1963	23.1
October 1963	10.3
November 1963	4.32
December 1963	3.71
January 1964	11.1
February 1964	8.54
March 1964	18.6
April 1964	28.5
May 1964	35.0
June 1964	38.0
July 1964	38.2
August 1964	33.4
September 1964	15.4
October 1964	7.52
November 1964	4.75
December 1964	15.6
January 1965	6.13
February 1965	8.45
March 1965	16.3
April 1965	25.1
May 1965	34.9
June 1965	35.4
July 1965	33.6
August 1965	26.9
September 1965	8.77
October 1965	4.92
November 1965	3.60
December 1965	4.06
January 1966	7.93
February 1966	8.72
March 1966	18.7
April 1966	27.7
May 1966	29.4
June 1966	27.0
July 1966	23.1
August 1966	13.4
September 1966	2.10
October 1966	0.010
November 1966	0.700
December 1966	3.92
January 1967	5.10
February 1967	9.23
March 1967	18.9
April 1967	28.9
May 1967	37.5
June 1967	39.2
July 1967	36.0
August 1967	23.0
September 1967	10.7
October 1967	7.28
November 1967	3.74
December 1967	3.89
January 1968	4.05
February 1968	11.9
March 1968	20.2
April 1968	26.7
May 1968	28.3
June 1968	30.8
July 1968	27.7
August 1968	19.8
September 1968	13.0
October 1968	8.89
November 1968	5.15
December 1968	4.82
January 1969	4.71
February 1969	9.02
March 1969	18.4
April 1969	27.0
May 1969	35.2
June 1969	39.1
July 1969	39.8
August 1969	36.9
September 1969	26.2
October 1969	9.04
November 1969	0.218
December 1969	4.13
January 1970	14.6
February 1970	12.3
March 1970	20.1
April 1970	26.2
May 1970	37.7
June 1970	38.5
July 1970	34.9
August 1970	28.4
September 1970	16.1
October 1970	6.29
November 1970	1.23
December 1970	2.23
January 1971	13.7
February 1971	10.3
March 1971	17.8
April 1971	28.5
May 1971	36.8
June 1971	39.2
July 1971	38.3
August 1971	27.6
September 1971	8.91
October 1971	0.132
November 1971	1.74
December 1971	5.06
January 1972	13.2
February 1972	9.67
March 1972	26.0
April 1972	30.0
May 1972	37.5
June 1972	38.9
July 1972	37.2
August 1972	32.8
September 1972	20.1
October 1972	6.10
November 1972	1.52
December 1972	2.19
January 1973	5.06
February 1973	10.6
March 1973	22.1
April 1973	34.2
May 1973	38.4
June 1973	38.5
July 1973	36.4
August 1973	32.9
September 1973	29.3
October 1973	10.8
November 1973	5.77
December 1973	3.87
January 1974	7.62
February 1974	9.40
March 1974	18.3
April 1974	28.7
May 1974	36.5
June 1974	39.7
July 1974	39.1
August 1974	36.6
September 1974	21.1

Rate and persistence

-0.68 Mm³

Mean drawdown per month over 12 months

5 of 24

Months in the last two years 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

Cottage Grove Lake Nr Cottage Grove, OR

Gauge location

Where this comes from

384 monthly observations 1942–1974 Mm³

Spatially aggregatedHigh confidenceSeptember 1974

Source: USGS — National Water Information System, 14153000. 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 25 August 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.