General Information Dam TRENTON DAM Missouri River Basin Project-- Nebraska Purpose: Flood control, diversion for irrigation, storage, sedimentation control, fish and wildlife preservation, and recreation Location: On Republican River, about 2-1/2 miles west of Trenton, Nebr. Constructed: 1949-1953 Water supply: Republican River Drainage area: 4,003 square Maximum flood: 200,000 second- Average yearly flow: 211 secondfeet (1947-1952) Reservoir: Official name: Swanson Lake Area: 7,975 acres at elevation 2773.0 Flood control storage: 133, 800 acre-feet, between elevations 2752.0 and 2773.0 Active irrigation storage: 116,100 acre-feet, between elevations 2710.0 and 2752.0 Dead storage: 4, 100 acre-feet, between elevations 2693.0 and 2710.0 Type: Zoned rolled-earth fill Height: 144 feet above lowest ex- Crest length: 8,600 feet Downstream, 10 to 1 to elevation 2710, 4 to 1 to elevation 2735, 2-1/2 to 1 to elevation 2760, and 2 to 1 to elevation 2793 Dam (Continued) Main cutoff trench: 50-foot base width with 1-1/2 to 1 side slopes, length about 6, 760 feet Auxiliary cutoff trench: 50-foot base width with 1-1/2 to 1 side slopes, length about 570 feet Spillway Type: Concrete overflow chute type with stilling basin Crest length of overflow section: 126 feet Crest: Elevation 2743.00 Maximum discharge: 126, 500 secondfeet at water surface elevation 2785.6 (as determined by model studies) Gates: Three, 42 by 30 feet Stilling basin: Reinforced concrete with dentated sills River Outlets Outlets: Two Invert: Elevation 2710.00 Gates: Four, 6 by 7.5 feet (two are installed in each outlet) Discharge capacity: 1,000 second-feet with reservoir water surface elevation at 2720.0 Canal Outlet Works Intake structure: Vertical shaft: 50 feet high Sill elevation: 2710.00 Outlet conduit: 5 feet 6 inches in diam- Outlet pipe: 56-inch-diameter pipe in Technical records of design and construction are a series of publications which record the planning, design, construction, and initial operation of Bureau of Reclamation projects and features. This technical record of design and construction of Trenton Dam is divided into six chapters. Chapter I contains general description, history and authorization, geology, and cost information. Chapter II is devoted to investigations of construction materials, and studies of railroad, highway, and county road relocations. Discussions on the design of the dam, spillway and river outlets, canal outlet works, and railroad structures are included in chapter III. Chapter IV contains discussions on contract administration and survey work. All phases of construction are discussed in chapter V. Chapter VI is devoted to test installations. This technical record was prepared in the Commissioner's Office, Denver, under the direction of the Assistant Commissioner and Chief Engineer. Acknowledgment is gratefully made to the designers and field personnel whose contributions formed the basis for this work. |