Negative of a photographic postcard showing the construction of the Detroit Dam in Detroit, Oregon. Taken from a nearby hillside, the view looks down on a dam that is halfway built across a river. A construction crew works on the dam. Handwriting on negative reads, "Detroit Dam Construction - Detroit, Ore. Christian S-129."

Negative of a photographic postcard showing the construction of the Detroit Dam in Detroit, Oregon. Handwriting on negative reads, "Detroit Dam Construction - Detroit, Ore. Christian S-77."

Photograph of 4 men wearing hard hats and standing in front of an SP&S train. Two of the hard hats are labeled, "Visitor." They look at the camera and smile. Handwritten note on the back of the print reads, "Left to right: Bill Harding - Mgr. A. GC., Bill Crosbie, Bill Fry, Frank Amerata. Contractor's special to McNary Dam, Thursday, June 3, 1954."

Photograph of a portion of the Bonneville Dam under construction. Construction workers work on the dam.

Photograph of a construction area located between the spillway of the Bonneville Dam and several railroad tracks. The Columbia River flows around the construction site and through the open spillways of the dam. There are 2 stamps on the back of the print. One is for Photo-Art Commercial Studios and the other for West Coast Engraving Co.

Photograph of a portion of the Bonneville Dam under construction. Two construction workers stand on construction materials that are suspended in the air, moving from one location to another.

Aerial photograph and survey of Bradford Island and the construction of the Bonneville Dam on the Columbia River. Written labels on the print indicate the locations of the fish hatchery, ship locks, power house, and more. Writing on the top right of the print reads, "Aerial view from 5,000 ft. elev. Bonneville Power and Navigation Project. Cost 32,200,000. Construction period - Nov. 1933 - Dec. 1937." Other writings on the print indicate this was taken on March 27, 1935 by Brubaker Aerial Surveys. Stamp on the back of the print requests that Brubaker be given credit for the photograph.

Photograph of a model of the Bonneville Dam. The model was built by U.S. Engineers, and labels mark the main dam, spillway, fish elevators, power house, and more. A railroad in the foreground of the model is labeled "Spokane, Portland & Seattle Ry." Additional writing on the print indicates the quantities and costs involved in building the dam. Copyright on bottom of print for Photo-Art Commercial Studios in Portland.

Photograph of a portion of the Bonneville Dam under construction. The mountains of the Columbia River Gorge are visible in the background.

Speakers seated on the stage at the Portland State College auditorium during a hearing on the construction of the Hells Canyon Dam (negative 7 of 7).

A man in a hardhat stands holding a metal cable beside the top of a cofferdam. Bonneville dam is visible in the background. The cofferdam was installed to clear water during a project to replace baffles at the base of the dam (negative 6 of 8).

Two men crouch next to a flowing channel of water in an indoor facility at the U.S. Engineers hydraulic laboratory at Bonneville, Oregon. A sign in the lower right of the photograph reads, "Oregon Shore." (negative 11 of 16).

Three men crouch next to a flowing channel of water in an indoor facility at the U.S. Engineers hydraulic laboratory at Bonneville, Oregon. A fourth man is visible holding a bucket and adding white strips to the water in the background (negative 8 of 16).

A two cranes on a packed-earth platform are in the process of removing a cofferdam around Bonneville Dam. The cofferdam was installed to clear water during a project to replace baffles at the base of the dam (negative 1 of 8).

Baffles on the front of Bonneville Dam exposed by low water behind a cofferdam. The cofferdam was installed to clear water during a project to replace baffles at the base of the dam (negative 4 of 8).

Photograph showing men working underneath a dam structure using a hose and pump. Layers of rock and silt can be seen in front of the men, with a large piece of basalt at the bottom of the frame. Written on the negative is "49-184." (Image note: see likely related images PGE 49-154, PGE 49-161, PGE 49-170, PGE 49-172, PGE 49-174, PGE 49-175, PGE 49-178, PGE 49-185).

Photograph showing a man in a diving helmet, partially submerged next to another man who is standing on a wooden board. The diving helmet is metal and has several openings. Written on the negative is "49-205. "(Image note: see likely related images PGE 49-154, PGE 49-161, PGE 49-170, PGE 49-172, PGE 49-174, PGE 49-175, PGE 49-178, PGE 49-184).

Photograph showing a short wooden dam structure on an unidentified river (possibly the Columbia River). Several men can be seen on top of the structure, on top of which water is being diverted from a pipe. Rock cliffs, wooded hills, and buildings can be seen in this distance. Written on the negative is "49-178." (Image note: see likely related images PGE 49-154, PGE 49-161, PGE 49-170, PGE 49-172, PGE 49-174, PGE 49-175, PGE 49-184, PGE 49-185).

Photograph looking upstream, below proposed upper dam site at Cazadero Dam/Station G. A railroad track and flume can be seen running into the distance around a hillside, and two possible construction vehicles are visible. The river can be seen on the left side of the frame.

Photograph of the Cazadero flume at generating Station G, showing a compressed air concrete mixer on a train car. Two men stand at either side of the mixer while looking at the camera.

Photograph showing the Faraday flume for generating Station G. Below the flume structure, the Clackamas River can be seen, with several small waterfalls flowing off the hillside above.

Photograph showing the Cazadero Dam flume running into the distance. Trees (possible burned) can be seen on both sides of the (excavated?) canal.

Photograph of the Cazadero flume at generating Station G, showing air compressor and pipelines weld, in placing concrete for new bents. Several cars can be seen on a railroad track, and the flume can be seen running along the right side of the frame.

Photograph taken from above Cazadero Dam/Station G, looking downriver towards the spillway and wooden dam structure. Behind, a dirt hillside and trees can be seen.

Photograph taken from a side angle, showing the flume at the Cazadero Dam/Station G. Below the wooden flume is a dirt hillside with rocks, and a long wooden building can be seen in the background on the right side of the frame.

Photograph looking towards flume and railway tracks at Cazadero Dam/ Station G. A man stands on the railway tracks in the distance, and a dirt hillside drops down between the tracks and the flume.

Photograph showing construction of Cazadero Dam. Several workers can be seen in the distance at the top of a stacked wooden dam structure, with a dirt hillside above. The Clackamas River is visible at the bottom of the dam, and trees (possibly burnt) can be seen at the top of the hill.

Photograph showing in-progress re-decking of the spillway at the Cazadero Dam/Station G. Men are visible at the top and bottom of the structure, and water and wood debris can be seen below the spillway.