The Department of the Army, U.S. Army Corps of Engineers, Walla Walla District, has a requirement for Little Goose Dam and Lower Monumental Dam Intake Gate Hydraulic System Upgrades.

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• Remove and dispose of existing cylinders, hydraulic power unit, piping, control stations, and other appurtenances.
• New hydraulic cylinders. Little Goose & Lower Monumental have only a partial set of cylinders. The cylinders that remain have been rehabilitated at least once and are in varying states of condition. Past experience with cylinder replacement at McNary indicates that performing a major rehabilitation of this type of cylinder approaches the cost of new. Additionally, new advances in superior cylinder rod coatings result in new cylinders being the preferred option. The system will be under pressure to keep the gates in the raised position.  19 new cylinders will be procured: 18 for normal operations plus one spare.
• New cylinder support beams. Each cylinder is supported in the slot by an H-shaped structural steel support. The project only has partial sets of beams currently (matching in quantity to the number of cylinders). To ensure compatibility with the new cylinders and to reset the life on the system, all new support beams will be procured. 19 new support beams will be procured, to match the number of new cylinders.
• New hydraulic power unit. The plant has a hydraulic power unit (HPU) consisting of two raise pumps and one pressurization pump.
• New control stations. The control station will be replaced at each main unit. The primary reasons for replacing each control station are age of the equipment, compatibility with new hydraulic fluid, and to be able to integrate the emergency closure control scheme. Six new control stations, one for each main unit, will be procured.
• New hydraulic fluid. The hydraulic fluid will be replaced due to age, condition, and environmental concerns. The existing conventional fluid will be replaced with an environmentally acceptable lubricant (EAL).
• New piping. All piping and hoses will be replaced due to age and condition.
• Gate position indication. The gate position indication system will be rehabilitated to become functional once again. Additionally, modifications will be made to provide gate position indication to the control room.
• Control system changes. Remote controls to initiate an emergency closure will be installed in the control room. Additionally, the functionality of the emergency closure switches on the governor actuator cabinets will be restored.
• Hydraulic fluid tank. The hydraulic fluid tank will likely be retained and rehabilitated.  Fire protection for the tank needs to be improved by either 1) relocating the tank, 2) adding a fire wall or 3) add a fire rated enclosure.