On our way to the Bridge of the Gods, we notice a National Historic marker and decide to explore the Bonneville Lock and Dam.
Built and operated by the U.S. Army Corps of Engineers, this was the first federal lock and dam on the Columbia-Snake Inland Waterway which stretches for 465 miles from the Pacific Ocean to Lewiston, Idaho.
Construction began in 1933, providing jobs during the Great Depression. FDR dedicated the facility in 1937.
The Lock and Dam are named after Army Captain Benjamin Bonneville who led an exploration to Oregon and charted extensive sections of what is now known as the Oregon Trail. (US Army Corps of Engineers brochure)
From 1941 to 2000 the turbine above helped produce enough hydropower for over 25,000 homes. During the Great Depression it created jobs. During World War II it supplied power to build aircraft and ships.
In order to protect the dam from attack during the war, armed guards stood in a “pill box” such as the one below. (plaques at site)
As the energy needs of the northwest grew, a second powerhouse was built between 1974 and 1981. The original powerhouse is located on the Oregon shore.
The second powerhouse is located on the Washington shore.
The spillway controls the amount of water released from the dam and regulates the water height. And yes, fish can survive the ride. ( Learn more about the fish in my next post.)
Notice how quickly the spill waters calm down.
The lock is necessary for transportation.
It allows ships to move cargo up river, eliminating the need to portage goods through the Cascades Rapids. Lewis and Clark had to portage around this impasse in 1805.
From 1878 to 1896 the Cascade Locks were built to make River navigation safer. Before the locks pioneers were forced to take the steep and dangerous route across Barlow Road or raft down the treacherous River. However, with the completion of the Bonneville Dam, the rising waters it created caused the submersion of these locks. (cascadelocks.net)
The Bonneville Lock of 1938 was the largest-single lift lock in the world but it could only hold 2 barges and a tugboat at one time. As river traffic increased, newer dams were added up river and were equipped with larger lock chambers. The original Bonneville Lock
was replaced in 1993. Lockage time that used to take several hours was now reduced to less than 30 minutes as the new lock chamber could hold up to 5 barge-tows. (US Army Corps of Engineers brochure)