The Pierre Shale of Upper Cretaceous Age underlies the dam and reservoir area at a depth of 175 feet below the valley floor. The Ogallala Formation of Pliocene Age unconformably overlies the Pierre Shale. The Ogallala Formation is composed of fine to course sand, some gravel, calcareous silt, silty sands, silts and clays. Various degrees of calcareous cementation occur, resulting in lenses of varying loose unconsolidated to very firm compact materials at irregular intervals. The Ogallala beds lie almost horizontal and structural irregularities, such as faulting, have been observed in the area. The overburden consists of alluvial materials on the valley floor and of reworked loess and slope wash materials on the valley sides. The alluvial materials are a mixture of fine sand and small pea gravel with a high percentage of chalk particles. The reworked loess ranges from sandy to clayey loam of low to moderate density. The slope wash is a mixture of loess and Ogallala talus resulting from colluvial action.
General
Project
PSMBP-Frenchman-Cambridge
Location
1.5 mi from Enders
Longitude
-101.5175
Latitude
40.4208
Watercourse
Frenchman River
Reservoir
Enders
Original Construction
1947-1951
National ID Number
NE01070
Dimensions
Crest Elevation
3137.5 ft
Structural Height
134.0 ft
Hydraulic Height (Normal Operating Depth at Dam)
93.0 ft
Crest Length
2603.0 ft
Top of Active Conservation Pool (Elevation)
3112.3 ft
Spillway Crest Elevation
3097.0 ft
Streambed at Dam Axis
3042.0 ft
Top of Inactive Conservation Pool (Elevation)
3082.4 ft
Top of Dead Storage Pool (Elevation)
3080.0 ft
Hydraulics & Hydrology
Spillway Capacity at Elevation
200000 cfs at 3129.0 ft
Outlet Works Capacity at Elevation
1431 cfs at 3129.0 ft
Hydrometeorological Report (HMR)
HMR 51 & 52
Normal Water Surface Elevation
3112.3 ft
Auxiliary Spillway
No
Drainage Area
1097 sq mi
Contact
Operator
Title: Area Office Manager Organization: Nebraska-Kansas Area Office Address: 1706 West Third City: McCook, NE 69001 Fax: 308-345-6470 Phone: 308-345-4400
Owner
Title: Area Office Manager Organization: Nebraska-Kansas Area Office Address: 1706 West Third City: McCook, NE 69001 Fax: 308-345-6470 Phone: 308-345-4400
More Information about the U.S. Bureau of Reclamation
