Detroit Dam
# Detroit Dam

Detroit Dam is a gravity dam on the North Santiam River between Linn County and Marion County, Oregon. It is located in the Cascades, about 5 mi (8.0 km) west of the city of Detroit. It was constructed between 1949 and 1953 by the United States Army Corps of Engineers. The dam created 400-foot (120 m) deep Detroit Lake, more than 9 miles (14 km) long with 32 miles (51 km) of shoreline.

It is one of the dams authorized by the Flood Control Act of 1938. Construction was delayed largely due to World War II. The dam, dedicated on June 10, 1953, was authorized for the purposes of flood control, power generation, navigation, and irrigation. Other uses are fishery, water quality, and recreation. It was built in concert with the Big Cliff Dam downstream.

In 2021, the U.S. Army Corps of Engineers determined that this dam was at risk of failing in a large earthquake in the Cascadia subduction zone, which would result in a "potentially catastrophic flood", which could potentially affect Oregon's state capital, Salem, located downstream. For this reason, the level of the reservoir was lowered by five feet, to reduce the stress on the concrete structure.

* Free-overflow spill test, 2013
* Top of Dam

## Capacity

* Drainage area: 437 mi² (1,132 km²)
* Maximum inflow: 63,200 ft³/s (1,790 m³/s) 1909
* Lake Elevation
   * Maximum pool: 1,574 ft (480 m)
   * Full pool: 1,569 ft (478 m)
   * Minimum flood control pool: 1,450 ft (442 m)
* Usable storage (1,425.0 to 1,563.5 ft) = 321,000 acre-feet (396,000,000 $m^3)$
* Powerhouse
   * Number of units: 2
   * Nameplate capacity: 100 MW
   * Overload capacity: 115 MW
   * Hydraulic capacity: 5,340 ft³/s (151 m³/s)
