Green Mountain Reservoir

(Redirected from Green Mountain Dam)

Green Mountain Reservoir lies at the northern end of Summit County, Colorado along the Blue River. The Green Mountain Dam was built between 1938 and 1942 by the United States Bureau of Reclamation. The reservoir and its dam store water to benefit Colorado's Western Slope. Created by President Roosevelt as part of the Colorado-Big Thompson Project in 1937, Green Mountain was the first facility to be constructed. This is because it represents a great compromise that made the C-BT project possible: it compensates the Western Slope for water diverted to cities in Northern Colorado from Lake Granby further upstream on the Colorado River. Water from Green Mountain Dam is released either over the spillway, through the dam, or through the hydroelectric powerplant at the dam's base. The Green Mountain Power Plant has the capacity to generate up to 21,000 kilowatts, using two generators. Combined with the other five Federal power plants on the C-BT, enough electricity is produced annually to power almost 60,000 American homes.[1]

Green Mountain Reservoir
Aerial view of the reservoir in 2017
LocationSummit County, Colorado
Coordinates39°52′39″N 106°19′50″W / 39.8776°N 106.3305°W / 39.8776; -106.3305
Construction began1938
Opening date1942
Dam and spillways
ImpoundsBlue River
Height309 ft (94 m)
Reservoir
CreatesGreen Mountain Reservoir
Total capacity153,000 acre⋅ft (189,000,000 m3)
Normal elevation7,950 ft (2,420 m)
Power Station
Installed capacity25MW

The reservoir has a capacity of 153,000 acre-feet (189,000,000 m3) of water. At maximum capacity, the elevation of the lake is 7,950 feet (2,420 m), and the dam is 309 feet (94 m) high. [2] The lake is popular with anglers, who catch rainbow trout, lake trout, brown trout, and kokanee. State Highway 9 follows the east side of the lake.[3] The town of Heeney lies on the western side, and the Green Mountain Reservoir Trail goes past the western side of the reservoir.

Climate edit

Climate data for Green Mountain Dam, Colorado, 1991–2020 normals, 1939-2020 extremes: 7740ft (2359m)
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Record high °F (°C) 60
(16)
58
(14)
67
(19)
77
(25)
86
(30)
95
(35)
97
(36)
93
(34)
95
(35)
84
(29)
67
(19)
62
(17)
97
(36)
Mean maximum °F (°C) 44.2
(6.8)
48.0
(8.9)
56.3
(13.5)
66.4
(19.1)
75.4
(24.1)
83.4
(28.6)
87.2
(30.7)
84.9
(29.4)
78.4
(25.8)
69.1
(20.6)
55.1
(12.8)
45.8
(7.7)
87.3
(30.7)
Mean daily maximum °F (°C) 27.8
(−2.3)
32.7
(0.4)
42.2
(5.7)
50.7
(10.4)
60.8
(16.0)
74.0
(23.3)
78.9
(26.1)
76.1
(24.5)
68.6
(20.3)
55.2
(12.9)
39.9
(4.4)
28.6
(−1.9)
53.0
(11.6)
Daily mean °F (°C) 15.7
(−9.1)
19.6
(−6.9)
28.5
(−1.9)
37.3
(2.9)
46.4
(8.0)
56.5
(13.6)
61.6
(16.4)
59.4
(15.2)
52.1
(11.2)
40.7
(4.8)
27.9
(−2.3)
17.5
(−8.1)
38.6
(3.7)
Mean daily minimum °F (°C) 3.7
(−15.7)
6.6
(−14.1)
14.9
(−9.5)
24.0
(−4.4)
31.9
(−0.1)
39.0
(3.9)
44.4
(6.9)
42.7
(5.9)
35.6
(2.0)
26.2
(−3.2)
15.9
(−8.9)
6.3
(−14.3)
24.3
(−4.3)
Mean minimum °F (°C) −16.9
(−27.2)
−17.9
(−27.7)
−4.4
(−20.2)
9.9
(−12.3)
21.6
(−5.8)
30.2
(−1.0)
37.3
(2.9)
34.6
(1.4)
23.7
(−4.6)
13.9
(−10.1)
−1.0
(−18.3)
−11.6
(−24.2)
−21.6
(−29.8)
Record low °F (°C) −41
(−41)
−46
(−43)
−26
(−32)
−11
(−24)
7
(−14)
21
(−6)
24
(−4)
24
(−4)
13
(−11)
1
(−17)
−17
(−27)
−26
(−32)
−46
(−43)
Average precipitation inches (mm) 1.13
(29)
1.06
(27)
1.21
(31)
1.95
(50)
1.66
(42)
1.06
(27)
1.57
(40)
1.63
(41)
1.46
(37)
1.40
(36)
1.05
(27)
1.28
(33)
16.46
(420)
Average snowfall inches (cm) 8.4
(21)
11.9
(30)
9.8
(25)
5.9
(15)
1.6
(4.1)
0.0
(0.0)
0.0
(0.0)
0.0
(0.0)
0.1
(0.25)
2.8
(7.1)
7.6
(19)
8.8
(22)
56.9
(143.45)
Source 1: NOAA (1981-2010 snowfall)[4][5]
Source 2: XMACIS2 (records & 1981-2010 monthly max/mins)[6]

See also edit

References edit

  1. ^ "Colorado-Big Thompson Project". Archived from the original on 2011-11-12. Retrieved 2011-05-09.
  2. ^ U.S. Department of the Interior: Water and Power Resources Service, Project Data, pps 251-292. United States Government Printing Office, 1981.
  3. ^ "Green Mountain Reservoir". FishExplorer.com. Retrieved 2019-09-02.
  4. ^ "Green Mountain Dam, Colorado 1991-2020 Monthly Normals". Retrieved December 9, 2023.
  5. ^ "Green Mountain Dam, Colorado 1981-2010 Monthly Normals". Retrieved December 9, 2023.
  6. ^ "xmACIS". National Oceanic and Atmospheric Administration. Retrieved December 9, 2023.