Photograph showing a spillway structure during the 1964 Christmas flood (taken December of 1964). Water can be seen rapidly spilling down the structure, with a small building visible at the far side of the river. High water levels can be seen upriver, in addition to forested hillsides and trees.

Photograph showing a camp at Big Sandy Dam, made up of wooden buildings surrounded by trees. Electric lines and utility poles can be seen throughout the image. Written on the negative is “339 Big Sandy Camp.”

Photograph showing a camp at Big Sandy Dam, made up of wooden buildings surrounded by trees. The buildings are in a row on a gradual incline, and piles of wood and cut trees can be seen. Written on the negative is “340 Big Sandy Camp.”

Photograph of river showing tunnel entrance and wooden structures along water edge. Wooded hillsides are seen at both sides of the river. Two men stand at the tunnel entrance.

Photograph of a train crossing the Sandy River bridge at Dodge Park, Bull Run. A total of eight passenger train cars can be seen crossing the trestle bridge, under which river rocks and water can be seen.

Photograph showing a wooden bridge at the Big Sandy Dam (likely the Marmot Dam). Water is flowing under the bridge, and in the distance several wooden structures and utility poles are visible. Written on the negative is “B.S.4.” (Image note: some discoloration visible at left side of image).

Photograph showing an excavated dirt canal, with visible water at the bottom level. In the distance, works can be seen along the sides of the canal, and a tunnel entrance is visible in the background. Written on the negative is “B.S-22.”

Photograph showing a man standing with construction debris during canal excavation for the Big Sandy Dam project (likely Marmot Dam). Large rock and pieces of wood can be seen throughout the image. In the background, other men can be seen next to a wooden wall. Written on the negative is “B.S.1.”

Photograph showing construction at the Big Sandy Dam (likely the Marmot Dam). Workers can be seen inside of a long wooden structure (flume?) while one can be seen at the top. On the right side of the frame is a loose hillside. Written on the image is B.S-35.”

Photograph showing construction at the Big Sandy Dam (likely the Marmot Dam). Multiple men can be seen standing on the wooden structure at the base of a loose hillside, while a wooden building and platform can be seen at the top of the frame. Written on the image is B.S-7.”

Photograph showing construction at the Big Sandy Dam (likely the Marmot Dam). Workers can be seen on the wooden structure, with flowing water at the right side of the image. In the background are several small wooden structures. Written on the image is “B.S. 32.”

Photograph showing the Big Sandy Dam (likely the Marmot Dam) spillway with flowing water, taken looking upriver. A wooden platform can be seen crossing the dam above the water. Written on the negative is “B.S. 47.”

Photograph showing construction at the Big Sandy Dam (likely the Marmot Dam). Several men can be seen standing on the wooden structure at the center of the frame. In the background, a wooden bridge crosses the river, surrounded by trees. Written on the image is B.S-19.”

Photograph showing the spillway of the Big Sandy Dam (likely the Marmot Dam) while under construction. Works can be seen standing at the top of the structure, while several wooden buildings can be seen in the background. Written on the image is “B.S. 26.”

Photograph showing construction at the Big Sandy Dam (likely the Marmot Dam). In the foreground, two men stand on top of the wooden spillway structure, while other works can be seen in the background towards the hillside. Gravel and more wood can be seen towards the top of the hill. Written on the image is B.S-37.”

Photograph showing construction at the Big Sandy Dam (likely the Marmot Dam). Several workers are visible on top of the wooden dam structure next to the Sandy River. Uphill are several small wooden platforms and buildings. Written on the negative is “BS-20.”

Photograph showing the Big Sandy Dam (likely the Marmot Dam) spillway with flowing water, taken looking upriver. A cement divider can be seen at the top of the spillway, in front of a small wooden structure and platform. Written on the negative is “B.S. 52.” (Image note: discoloration visible at right side of image).

Photograph showing three men in suits standing in a dirt excavation area. Wood and gravel litters the ground throughout the excavated area. The man on the right looks downward at the ground.

Photograph showing two men with a horse towing a metal cart on a railroad track. The horse is attached to the cart via a harness, with the reins being held by one of the individuals. In the background are trees and a hillside.

Photograph showing a man kneeling at the top of the tunnel entrance at the Big Sandy Dam (likely the Marmot Dam). He is holding a labeled measuring stick that extends into the water below. (Image note: some discoloration at edges of negative).

Photograph showing a loose hillside with railroad tracks and a gravel pit at the Big Sandy Dam (likely the Marmot Dam). Multiple men can be seen standing on and near the tracks. At the top of a hill is a small wooden structure and platform. Written on the negative is “B.S.56.”

Photograph showing a temporary wooden dam at the Big Sandy Dam site (likely the Marmot Dam). Two workers stand on the wooden structure while looking upward at the camera. In the background, sandbags, woodpiles, and work tools can be seen. Written on the negative is “#33, Spillway in tempy dam at Big Sandy, Oct 21, ‘11.”

Photograph showing construction of the tunnel at the Big Sandy Dam (likely the Marmot Dam). A man stands next to a machine next to the tunnel entrance, which is emitting a large plume of steam. Wood and gravel is visible throughout the image. Written on the negative is “B.S. 48.”

Photograph showing several temporary tent structures in a large field. Is the distance, another structure can be seen, in addition to trees and hills. (Image note: discoloration of the negative is visible at the center of the frame, in addition to a small damaged area also near the center).

Photograph showing exterior of wooden and steel structure of flume at Bull Run.

Photograph of Bull Run flume showing a motorcar and man in a hat and suit.

Photograph of a governor device at Bull Run. A large wheel is on the front of the machine.

Interior image of Station O room with governor and generator devices.