The navigation lock at Lower Granite Dam is 674 feet long, 86 feet wide and 122 feet high with a water volume capacity of approximately 46,000,000 gallons. The lock is gravity filled and drained by operating a series of large submersible tainter gates. Annually, the lock services over 1,500 lockages transporting millions of tons of cargo (fertilizer, petroleum, wood products, grain, etc…) to and from the inland port in Clarkston, WA to the Pacific Ocean.