Fern Ridge Lake, OR — storage

Storage now, against this reservoir's own record

102.77 Mm³

Stored, September 1974

66th

Percentile among 33 Seps on record

+16.0%

Change over the 12 months to 1974-09

Storage in September 1974 was around the middle of the Sep record, ranked against 33 other Seps held for this reservoir.

Storage, 1941–1974

Monthly mean storage

393 monthly values, 1941 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	Fern Ridge Lake Near Elmira, OR (Mm³)
December 1941	43.5
January 1942	33.6
February 1942	29.7
March 1942	47.8
April 1942	62.7
May 1942	74.7
June 1942	84.1
July 1942	85.0
August 1942	75.9
September 1942	37.0
November 1942	27.5
December 1942	97.3
January 1943	92.3
February 1943	89.8
March 1943	70.6
April 1943	124
May 1943	125
June 1943	124
July 1943	119
August 1943	109
September 1943	107
October 1943	105
November 1943	38.7
December 1943	4.98
January 1944	4.53
February 1944	12.3
March 1944	34.0
April 1944	54.7
May 1944	66.3
June 1944	71.7
July 1944	70.9
August 1944	68.0
September 1944	65.4
October 1944	61.1
November 1944	11.3
December 1944	8.58
January 1945	8.99
February 1945	32.5
March 1945	71.3
April 1945	107
May 1945	123
June 1945	124
July 1945	120
August 1945	115
September 1945	110
October 1945	52.8
November 1945	12.1
December 1945	17.3
January 1946	34.7
February 1946	28.2
March 1946	67.7
April 1946	101
May 1946	111
June 1946	113
July 1946	110
August 1946	104
September 1946	93.0
October 1946	22.7
November 1946	11.2
December 1946	11.6
January 1947	10.1
February 1947	35.3
March 1947	79.7
April 1947	109
May 1947	119
June 1947	123
July 1947	122
August 1947	120
September 1947	116
October 1947	65.9
November 1947	16.3
December 1947	9.53
January 1948	49.7
February 1948	36.5
March 1948	69.2
April 1948	108
May 1948	124
June 1948	124
July 1948	123
August 1948	118
September 1948	114
October 1948	53.8
November 1948	9.12
December 1948	16.1
January 1949	9.10
February 1949	52.3
March 1949	69.9
April 1949	93.2
May 1949	116
June 1949	119
July 1949	114
August 1949	109
September 1949	89.6
October 1949	15.6
November 1949	8.75
December 1949	9.10
January 1950	35.3
February 1950	32.8
March 1950	68.2
April 1950	105
May 1950	120
June 1950	122
July 1950	118
August 1950	110
September 1950	94.9
October 1950	46.9
November 1950	40.2
December 1950	10.3
January 1951	37.6
February 1951	32.5
March 1951	68.2
April 1951	93.2
May 1951	104
June 1951	106
July 1951	100
August 1951	78.4
September 1951	24.9
October 1951	9.08
November 1951	9.17
December 1951	20.7
January 1952	9.22
February 1952	29.4
March 1952	67.9
April 1952	96.9
May 1952	106
June 1952	106
July 1952	108
August 1952	96.0
September 1952	62.8
October 1952	20.2
November 1952	10.1
December 1952	9.08
January 1953	36.8
February 1953	36.6
March 1953	67.2
April 1953	101
May 1953	123
June 1953	124
July 1953	123
August 1953	113
September 1953	89.9
October 1953	37.9
November 1953	16.7
December 1953	19.8
January 1954	26.6
February 1954	49.6
March 1954	65.5
April 1954	107
May 1954	121
June 1954	123
July 1954	121
August 1954	105
September 1954	77.7
October 1954	35.7
November 1954	14.1
December 1954	8.32
January 1955	9.31
February 1955	25.9
March 1955	67.7
April 1955	111
May 1955	125
June 1955	124
July 1955	121
August 1955	106
September 1955	62.0
October 1955	14.3
November 1955	14.3
December 1955	58.8
January 1956	67.3
February 1956	35.4
March 1956	64.0
April 1956	101
May 1956	113
June 1956	115
July 1956	110
August 1956	102
September 1956	72.4
October 1956	27.7
November 1956	10.2
December 1956	9.82
January 1957	7.81
February 1957	38.9
March 1957	85.2
April 1957	113
May 1957	126
June 1957	126
July 1957	121
August 1957	111
September 1957	80.6
October 1957	40.5
November 1957	13.0
December 1957	30.7
January 1958	16.3
February 1958	47.8
March 1958	76.3
April 1958	112
May 1958	126
June 1958	127
July 1958	122
August 1958	112
September 1958	89.6
October 1958	54.0
November 1958	16.3
December 1958	9.77
January 1959	34.5
February 1959	37.1
March 1959	60.8
April 1959	106
May 1959	117
June 1959	118
July 1959	113
August 1959	104
September 1959	63.6
October 1959	30.0
November 1959	12.0
December 1959	8.75
January 1960	11.0
February 1960	45.2
March 1960	82.5
April 1960	114
May 1960	125
June 1960	127
July 1960	123
August 1960	116
September 1960	111
October 1960	62.8
November 1960	22.8
December 1960	9.71
January 1961	10.2
February 1961	67.0
March 1961	79.1
April 1961	109
May 1961	124
June 1961	125
July 1961	120
August 1961	113
September 1961	108
October 1961	61.8
November 1961	16.4
December 1961	16.6
January 1962	8.98
February 1962	28.0
March 1962	80.2
April 1962	110
May 1962	124
June 1962	124
July 1962	119
August 1962	113
September 1962	108
October 1962	62.6
November 1962	17.8
December 1962	11.6
January 1963	9.18
February 1963	33.9
March 1963	65.4
April 1963	114
May 1963	127
June 1963	126
July 1963	124
August 1963	120
September 1963	114
October 1963	59.7
November 1963	16.8
December 1963	8.96
January 1964	38.9
February 1964	22.3
March 1964	65.8
April 1964	99.0
May 1964	106
June 1964	107
July 1964	103
August 1964	97.7
September 1964	64.8
October 1964	7.83
November 1964	9.29
December 1964	50.7
January 1965	50.0
February 1965	31.5
March 1965	51.5
April 1965	66.5
May 1965	80.8
June 1965	81.7
July 1965	77.9
August 1965	73.0
September 1965	67.2
October 1965	35.2
November 1965	11.6
December 1965	13.0
January 1966	52.3
February 1966	31.0
March 1966	78.1
April 1966	112
May 1966	117
June 1966	113
July 1966	107
August 1966	99.1
September 1966	92.4
October 1966	40.6
November 1966	13.7
December 1966	10.4
January 1967	15.8
February 1967	36.6
March 1967	72.5
April 1967	111
May 1967	128
June 1967	127
July 1967	120
August 1967	111
September 1967	102
October 1967	70.8
November 1967	15.7
December 1967	10.1
January 1968	11.1
February 1968	42.8
March 1968	92.3
April 1968	117
May 1968	123
June 1968	125
July 1968	118
August 1968	110
September 1968	109
October 1968	72.5
November 1968	19.7
December 1968	21.8
January 1969	22.2
February 1969	33.4
March 1969	75.9
April 1969	101
May 1969	110
June 1969	113
July 1969	111
August 1969	101
September 1969	93.1
October 1969	65.1
November 1969	15.6
December 1969	12.9
January 1970	39.2
February 1970	59.3
March 1970	76.8
April 1970	99.6
May 1970	113
June 1970	113
July 1970	106
August 1970	96.0
September 1970	87.7
October 1970	61.0
November 1970	11.0
December 1970	9.53
January 1971	48.3
February 1971	52.3
March 1971	90.6
April 1971	125
May 1971	126
June 1971	126
July 1971	123
August 1971	113
September 1971	108
October 1971	72.7
November 1971	16.8
December 1971	11.0
January 1972	39.8
February 1972	40.5
March 1972	100.0
April 1972	124
May 1972	126
June 1972	127
July 1972	120
August 1972	111
September 1972	103
October 1972	77.0
November 1972	16.6
December 1972	9.93
January 1973	15.4
February 1973	36.2
March 1973	72.1
April 1973	106
May 1973	115
June 1973	113
July 1973	106
August 1973	95.8
September 1973	88.6
October 1973	63.9
November 1973	26.2
December 1973	19.3
January 1974	52.8
February 1974	37.9
March 1974	79.1
April 1974	118
May 1974	126
June 1974	125
July 1974	120
August 1974	111
September 1974	103

Rate and persistence

+1.18 Mm³

Mean change per month over 12 months

2 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

Fern Ridge Lake Near Elmira, OR

Gauge location

Where this comes from

393 monthly observations 1941–1974 Mm³

Spatially aggregatedHigh confidenceSeptember 1974

Source: USGS — National Water Information System, 14168000. 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.