Lower Monumental Navigation Lock Power and Controls Upgrade

The U.S. Army Corps of Engineers (USACE) Walla Walla District intends to issue a construction solicitation for a project titled Lower Monumental Navigation Lock Power and Controls Upgrade. The work will take place at Lower Monumental Dam in Franklin County, Washington. Lower Monumental Lock and Dam is a hydroelectric, concrete, run-of-the river dam located on the Snake River in southeast Washington; Six miles south of Kahlotus and 43 miles north of Walla Walla. Construction of the Lock and Dam was completed in 1969. The existing navigation lock electrical unit substation, switchgear, transformers, and motor control centers are original to the dam and have been operating for over 55 years. The equipment has far exceeded the typical equipment service life and needs to be replaced. The age of the equipment has made procuring replacement parts difficult. Operation and maintenance of the equipment remains more hazardous to workers due to the age and arc flash category rating of the equipment. Failure of the electrical system could impact the operation of the lock which would ultimately affect navigation on the Snake River. This project will replace the existing navigation lock electrical power system, associated controls, and provide a new modern HMI screen depicting breaker position. To reduce the impact to river traffic, an extended outage will be provided for this project. The work window in the extended outage is expected to be 5-9 weeks. All work must be complete in order to return the Navlock to service. Management of the construction schedule is critical to completion of this project on time. Any delays to reopen is a significant impact to the Navigation Industry. The main features of work include: 1. Provide new upstream and downstream medium voltage switchgear LSP1 and LSP2. 2. Provide new 4,160-V motor control for existing unwatering pumps. 3. Provide upstream and downstream low voltage switchgear LSQ1 and LSQ2. 4. Provide new Motor Control Center (MCC) LSQ1.A, LSQ2.A, LSQ2.B. 5. Provide new controls for existing electrical loads. 6. Provide two (2) new 4,160/480-V 1,500 kVA transformers. 7. Provide lighting load centers to replace existing panels. 8. Provide all new feeders that are currently fed from LSQ1 and LSQ2 equipment. 9. Provide LSP1 and LSP2 4,160-V feeders connecting the station service switchgear. 10. Provide new concrete housekeeping pads for new electrical equipment. 11. Provide new cable tray and conduits where required by circuit reconfigurations and to bring fill ratios to levels that meet national electrical codes. 12. Provide a full redundant emergency feed to switchgear LSQ1 and LSQ2 through the use of a main-tie-main configuration. 13. Provide HMI screens to replace the existing annunciator panel for LSP1, LSP2 and control room. 14. Provide new lighting for both LSP1 and LSP2 substation rooms. 15. Grade existing LSP1 and LSP2 concrete floors to allow for positive flow to existing floor drains. 16. Replace in kind the existing environmental controls and equipment in both LSP1 and LSP2 substation rooms. 17. Install air quality filters for the inlet flow of both switchgear rooms. 18. Provide Heating, Ventilating, and Air-conditioning systems serving the substation rooms with temperature and humidity control. 19. Replace the existing doors for both up and downstream substation rooms. 20. Seal the road deck above both substation rooms. 21. Install new drop ceiling in the breakroom. 22. Demolish the existing switchgear, motor controls centers, and transformers making up the LSP1 and LSP2 lineup. 23. Demolish the existing feeders routed from LSQ1 and LSQ2 switchgear and motor control centers. 24. Demolish the existing medium-voltage feeders supporting the existing lock unwatering pumps number 1 and 2. 25. Demolish lighting in both LSP1 and LSP2 substation rooms. 26. Demolish existing mechanical environmental controls and equipment in LSP1 and LSP2 substation rooms. 27. Demolish the existing breakroom ceiling and light fixtures.

Dam/Tunnel, Renovation.

Division 02 -	Existing Conditions, Subsurface Investigation.
Division 31 -	Earthwork, Site Clearing, Grading, Excavation and Fill, Subgrade Preparation, Excavation, Shoring, Tunneling and Mining, Tunnel Excavation.
Division 35 -	Waterway and Marine Construction, Dam Construction and Equipment.