Photograph looking downhill at the Clackamas River, at a potential future dam site for the River Mill Dam. Several cut trees can be seen on the closest hillside, and a rocky ledge is visible across the river. Written on the negative is “Dec 22, ‘09, PES 2013.”

Photograph of River Mill Dam looking upstream. The powerhouse can be seen to the right of the large dam structure, with a smaller wooden building to the front. In the background, a distant railroad bridge can be seen.

Photograph showing the Clackamas River in the River Mill area, with numerous “islands” and cliffs. A wooden suspension bridge can be seen spanning two cliffs near the center of the frame, with numerous wooden buildings visible in the distance. Written on the negative is “#58M. 8-12-10.”

Photograph looking downstream looking towards the “island,” with a wooden suspension bridge visible. In front of the bridge a blurry man can be seen facing the camera. Beyond the bridge is a small wooden building next to several vertical poles. Written on the negative is “#60M. 10-10.”

Photograph showing the construction of the spillway at the River Mill Dam. At the left side of the frame, a portion of a wooden suspension bridge can be seen. Behind, a railroad bridge spans the space between two cliffs, beyond which wooden buildings are visible. Written on the negative is “#84M. 1-28-11.”

Photograph looking across the Clackamas River, of a potential dam site for the future River Mill Dam. A rocky cliff-face can be seen across the water, as well as tree at the top of the frame. Written on the negative is “Oct 22, ‘09, PES #2004.”

Photograph showing the exterior of the River Mill Dam powerhouse, likely shortly after construction. Loose hillsides can be seen to the left and right of the building, with transmission lines throughout (image note: corner of glass negative is broken and missing).

Photograph taken from a side angle of the River Mill Dam and powerhouse, showing exterior of building and view of dam structure. Water from the Clackamas River can be seen moving over the dam, and trees and transmission lines are visible in the distance.

Photograph of the River Mill Dam, showing recently cut trees and possibly dam structure under construction. Water can be seen at the front of the frame.

Photograph from the interior of Station M at the River Mill Dam showing governor #3 during a test. On the device is written “The Lombard Governor Co.”

Photograph showing the left bank of the Clackamas River at the river Mill Dam, taken from the “island.” Near the center of the frame, two men in long jackets stand next to a surveying station. To the left, another man in a hat and jacket looks at the camera. In the distance, men can be seen working on the dam spillway. Written on the negative is “#70M. 11-28-10.”

Photograph taken from the side showing water cascading over the River Mill Dam. Across the water, the powerhouse for Station M can be seen.

Photograph of the Clackamas River looking upstream, near the River Mill Dam.

Photograph of the interior of the River Mill Dam (Station M) showing heavy head gate machinery. Several rows of large gears are visible, and large windows can be seen on all walls.

Photograph showing the camp at the River Mill Dam site, taken from the top of the railroad bridge. Snow blankets the ground throughout the image, and numerous wooden buildings an be seen. Written on the negative is “82M.”

Photograph showing a partially completed suspension bridge over the Clackamas river near the River Mill Dam site. Cliffs and trees can be seen throughout the image. Written on the negative is “Dec 22, ‘09 – PES 2009.”

Photograph showing a bridge over the Clackamas River, taken from river level looking upward. In the background, a wooden suspension bridge can be seen across the cliffs behind the larger front bridge. Written on the negative is “Dec 22, ‘09 PRD 2007.”

Photograph of the River Mill Dam powerhouse taken from a high angle, looking downwards. In the background, the dam structure and transmission lines can be seen.

Photograph of the interior of the River Mill Dam (Station M) showing generator machinery. Written on the side of the front unit is “General Electric Company.” Three people can be seen in the photo, two of which are looking at the camera.

Photograph showing a suspension bridge over the Clackamas River in near the River Mill dam area. The bridge crosses between two tall cliff faces, beyond which the river can be seen around. Snow is on the ground throughout the image. Written on the negative is “Feb 3, ‘10, PES 2014.”

Photograph taken from a bridge and looking downriver at the River Mill Dam and powerhouse. The Dam structure can be seen on the left, with the powerhouse building on the right.

Photograph showing the camp at the River Mill Dam site, taken from the top of the railroad bridge. Snow blankets the ground throughout the image, and numerous wooden buildings an be seen. Written on the negative is “82M.”

Photograph showing the Clackamas River in the river Mill area, with numerous “islands” and cliffs. In the distance, a railroad track crossing a bridge is visible. Cut trees can be seen at the right side of the frame. Written on the negative is “#M56. 8-1910.”

Photograph showing a group of seated people outside a stone building, with a man standing and facing the group next to a stairway. A sign on the building reads "River Mill Hydroelectric Project," and a river and trees can be seen in the background. Written on the negative is "51-864."

Photograph showing a man wearing a long jacket standing on a raised cement platform. He is looking towards three large electrical units with belts, and water can be seen under the platform. In the background is a wooded hillside. Written on the negative is "51-868."

Negative of a photographic postcard showing the Mill River Power Plant at the River Mill Dam in Estacada, Oregon. Water from the Clackamas River goes over the spillway in the background. Power lines carry electricity from the plant. Handwriting on negative reads, "Mill River Power Plant - Estacada, Ore. Christian 11-6007."

Negative of a photographic postcard showing the Mill River Power Plant at the River Mill Dam in Estacada, Oregon. Water from the Clackamas River goes over the spillway. Handwriting on negative reads, "Mill River Power Plant - Estacada, Ore. Christian 11-6010."