Wyoming State Water Plan, Wyoming Water Development Office
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Northeast Wyoming River Basins Water Plan
Technical Memoranda

SUBJECT: Appendix J
Storage Operation and Description
SPENCER

PREPARED BY: HKM Engineering Inc.

DATE: March 2002




KEY STORAGE FACILITIES
Reservoir: SPENCER (or LAK, ENL OF 1890R & 4917R)
Date: 12 Feb. 2001
Location: SWNE 6,T44N,R60W
Owner: TRUE RANCHES, INC.
Year of Construction: 1910
Enlargement History: 1940, 1953
Total Storage: 2,847 acre-feet
Active Storage: 2,162 acre-feet
Dead Storage: Data not available
Area/Capacity Data: (Source: Feb. 1941 "Map to Accompany Application for Enlargement of Spencer Reservoir," The Ohio Company, applicant, on file in SEO Safety of Dams office.)

Contour Area
(acres)
Capacity
(af)
1015 104


467
1010 83


390
1005 73


320
1000 55


207
995 28


108
990 15


62
965 10


33
980 3
TOTAL 104 1587
Dam Construction Type: Earth Fill
Outlet: Two 18" x ΒΌ" welded steel pipes, asphalt coated, "placed on six- inch centers," (permit). This could mean the pipes were placed with their walls six inches apart.
Spillway: 100 x 5-foot, rock-lined channel cut in the crest of the dam
End-of-Month Storage Records:No
Water Rights: (Source: Tabulation of Adjudicated Surface Water Rights of the State of Wyoming, Water Division Number Two, Oct. 1999)
Reservoir Permit Number Permitted Use Priority Date Volume (af) Headgate Location (S-T-R)
Spencer Res 1890R I 07-05-1910 98.28 31-45-060
Enl. Spencer 4917R I 06-18-1938 1489 6-44-060
Enl. Spencer 5410R I 02-12-1941 575 6-44-060
Designated Use: Irrigation
Associated Irrigation Diversions: Information not available.
Associated Irrigation Diversions: (Source: Tabulation of Adjudicated Surface Water Rights of the State of Wyoming, Water Division Number Two, Oct. 1999)
Diversion Permit Priority Date Permitted use Flow (cfs)
L A K Power Plant 17853 03-27-1931 Power 12
References: Map to Accompany Application for Enlargement of Spencer Reservoir, the Ohio Company, Newcastle, Wyoming, 3 Feb. 1941.

Tabulation of Adjudicated Surface Water Rights of the State of Wyoming, Water Division Two, Oct. 1999.

Spencer Dam cross sections ("Map to Accompany Application for Enlargement of Spencer Reservoir", the Ohio Company, Newcastle, Wyoming, 3 Feb. 1941):

Net evaporative loss for Spencer Reservoir:

Lewis Annual Evaporation 40
Total Storage 2,847


Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Average percent of storage 54.3 58.0 66.5 69.8 76.5 78.1 76.6 74.4 72.2 53.8 53.5 53.7
Generated storage (acre-feet) 1546 1653 1894 1988 2177 2222 2182 2117 2056 1531 1523 1528
Corresponding area (acres) 103.2 105.2 109.8 111.5 115.1 115.9 115.1 113.9 112.8 102.9 102.8 102.9

Calculations:
Monthly Lewis Evap. (inches) 1.08 1 1.56 3.2 4.6 5.24 6.84 6.24 4.6 3.04 1.56 1.04
Monthly Precipitation (inches) 0.25 0.75 0.75 1.75 2.75 2.75 1.75 1.75 1.25 0.75 0.75 0.75
Net Evaporation (inches) 0.83 0.25 0.81 1.45 1.85 2.49 5.09 4.49 3.35 2.29 0.81 0.29 TOTAL
Total Net Evaporation (acre-feet) 7 2 7 13 18 24 49 43 31 20 7 2 224