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I I I I I I I I I I I I I I I I I I I B. RESERVOIR NO. 5 B.t. Physical Plan 1. Existing Facilities. Reservoir No. 5 Is Impounded by one dam that runs In approximatelY an east to west direction as shown on the plan on Figure V-7. The main dsm Is approximately 2100 feet long with a structural height at the outlet of approximately 34 feet. The dam embankment upstream slopes vary from 3H (horizontal) to 1 V (vertical) to as flat as 5H to IV. The downstream slopes are generally 3H to IV except In the area of the outlet. The crest of the dam varies In width from 16 feet to as much as 50 feet and serves as the access road across the dam. No problems exist with the upstream embankment slopes as they were re-sloped and repaired during the 1980 rehabilitation. The downstream slopes are also adequate except In the area of the outlet works where the embankment Is oversteep and has eroded significantly. Some seepage problems exist along the downstream toe of the dam In the area of the outlet and Is the main reason the reservoir Is under restriction by the State Engineer. The dam has a 250 foot wide spillway located at the right abutment which provides 6.1 foot of freeboard at the normal pool. The spillway has no fixed control wall and Is protected by rlprap only at the control section. The spillway was also upgraded during the 1980 rel1abllltatlon and It Is not expected to need any further modifications. The outlet works consists a concrete Inlet box, a 2'-4" by 3'-0" masonry outlet conduit, and a masonry and concrete gatehouse In the center of the dam containing the gate and operator. The conduit has no outlet control structure or energy dissipation structure. The upstream end of the conduit was modified with the latest rehabilitation In 1980. The Intake control structure Is new and the first 64 feet of the conduit consists of a 2'-4" by 3'-0" concrete box culvert type conduit. The outlet end of the conduit was also modified and 46 feet of concrete box culvert added In 1980. The remaining 91 feet of the conduit In the central portion of the dam Is the orlglJ\al sandstone masonry outlet conduit. The date of Installation of this outlet works Is not known for sure but Is assumed to be from the original dam construction. The outlet gate operates properly but Is In somewhat poor condition. The operator takes a lot of torque to open the gates as It Is not geared properly for the size and weight of gate used. The gate and operator need to be replaced. The gatehouse Is In need of some repslr as the lower portion of the well Is of masonry construction. The upstream slope protection Is In good shape as It was upgraded and repaired during the 1980 rehabilitation. PAGS 17 Cliapler V - 10. 6 Peuiblllty