About ten miles north of Redding is the Shasta Dam, an arch dam across the Sacramento River. The dam mainly serves long-term water storage and flood control in its reservoir, Shasta Lake, and also generates hydroelectric power. At 602 feet high, it is the ninth-tallest dam in the United States and forms the largest reservoir in California, Lake Shasta. Dams are measured by the amount of concrete used and Shasta Dam is the second largest dam in the country by this measurement. Only the Grand Coulee Dam is larger. The day of our visit smoke from nearby fires obscured the mountains beyond the dam. Below is a picture we took of the dam. Note the lack of mountains in the distance.
Below is a picture borrowed from the Web taken on a clear day. Note the 14,ooo ft. Mt. Shasta in the distance. We didn’t even know it was there during our visit.
There is a visitor’s center next to the dam and free tours are conducted throughout the day. To take the tour you register at the visitor’s center then walk a half mile to the second tower in the middle of the dam. After going through a security check the TSA would be proud of, you take an elevator down 428 feet to near the base of the dam. Galleries (or tunnels) were built into the dam and are used for visual inspections. The gallery used by visitors has been finished with green tile and terrazzo flooring. The acoustics in the gallery are perfect. If you clap your hands in this long gallery, you can hear that clap as it travels down the gallery at the speed of sound and echoes back to you – at 758 miles per hour!
Shasta Dam’s spillway is used to provide flood control – the 18 valves, or outlets, seen on the face of the dam allow operators to manage the lake level, providing flood control downstream. At the top are massive steel drum gates, also used in the management of the lake level.
Our guide pictured below is standing next to a painted area on the wall. This area is the size of one of the outlets on the spillway.
Five penstocks deliver water to the generators in the power plant. Water stored in Shasta Lake goes through a penstock and into a turbine, spinning the generator, producing hydroelectric power.
To get some perspective on the size of each penstock, look at the stairways in the picture above. Below is a picture of a penstock during construction. Note the worker guiding it on to a cradle for movement.
One of the cradles used in construction is on display at the entrance to the power plant.
The power plant has five large turbines producing enough power to fill the electrical needs of San Francisco and one small turbine that provides power to the dam. Only about one fourth of each turbine is visible.
The early phase of dam construction also included moving over 30 miles of Southern Pacific Railroad track which was running right through the dam site. Moving the train was a major undertaking, and required the building of many bridges, trestles and tunnels. One tunnel was built right through the hillside to temporarily detour the train around the dam site so excavation of the western abutment could begin. After the new train track was completed, the Southern Pacific Railroad was ready to run on its new course. With this relocation, workers at the dam site were now able to divert the Sacramento River through the same tunnel that was used earlier as a temporary detour for the train. This allowed them to clear out the original river channel and complete the construction of the dam.
Once the dam was completed they blocked the tunnel at it’s mid-point. The north side is now under water as part of the lake while the southern end is used for storage.
The tour takes about an hour and requires a bit of walking, but the cool of the dam interior (sixty-five degrees) was a nice relief from the hundred degree temperatures outside. All in all the Shasta Dam is a great place to visit.