Foster Dam is an embankment type rock-fill

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, a ...

across the

South Santiam River The South Santiam River is a tributary of the Santiam River, about long, in western Oregon in the United States. It drains an area of the Cascade Range into the Willamette Valley east of Corvallis. It rises in the Cascades in southeastern Linn ...

near

Sweet Home Sweet Home or Sweethome may refer to: Places in the United States * Sweet Home, Arkansas * Sweet Home Central School District in Amherst and Tonawanda, New York ** Sweet Home High School (Amherst, New York), a New York State public high school * ...

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

, United States. Designed by the Corps of Engineers, it began service on August 22, 1968. Its primary purpose is

flood control Flood control methods are used to reduce or prevent the detrimental effects of flood waters."Flood Control", MSN Encarta, 2008 (see below: Further reading). Flood relief methods are used to reduce the effects of flood waters or high water level ...

but it also provides power, navigation improvement downstream and

irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...

. The damming of the river created

Foster Reservoir Foster Reservoir is a reservoir created by Foster Dam on the South Santiam River in the city of Foster, Oregon, United States. The reservoir is approximately long and covers approximately when full. Primary use of the reservoir is recreation i ...

, which is a popular fishing and water sports area. The reservoir stores . The powerhouse has two generators with a capacity totaling 20 MW. The dam regulates water flow from the main facility,

Green Peter Dam Green Peter Dam is a concrete gravity dam impounding the Middle Santiam River in Linn County in the U.S. state of Oregon. It was completed in 1967 to generate hydroelectricity, prevent flood damage, provide irrigation, and improve water quality ...

Risk to fish

The

Pacific Northwest National Laboratory Pacific Northwest National Laboratory (PNNL) is one of the United States Department of Energy national laboratories, managed by the Department of Energy's (DOE) Office of Science. The main campus of the laboratory is in Richland, Washington. O ...

tested the likely effects of the dam on fish populations using the

sensor fish A sensor fish is a small, plastic tubular device containing sensors. It is designed to record information such as the physical stresses that a fish experiences while navigating currents from dam turbines. Description Created by the US Department ...

. They concluded that all fish travelling over the spillway fish weir would probably experience a minimum of one significantly stressful event. This is due to the absence of a cushioning effect due to the shallow flow depth and badly formed discharge jet. In fact, most fish would likely experience many events while tumbling down the spillway. Because of the larger size of actual fish, the study concluded that live fish would experience even greater events than the sensor fish. Most injuries sustained by smolt (juvenile salmon) after they had passed through the weir were caused by the weir jet's shallow depth as well as the angle of the jet as it struck the spillway chute. Over 22% of the sensor fish were damaged or lost in the turbine tests. The devices showed signs of "grinding or squeezing". It is assumed that this happened while being compressed when travelling between the blades of the turbine. Although turbine pressures were similar to Kaplan turbines at the Snake River dams and Columbia River dams, significant events were recorded by the sensor fish occurred at a rate 2-3 times more frequently at the Foster Dam. Rates of injury and mortality for live fish were correspondingly higher. When comparing the two passage routes, data show that fish travelling over the weir experienced greater event magnitudes than fish travelling through the turbine. This is because of the eventual impact the fish experienced at the spillway chute. The study suggests that possible spillway weir design changes and increasing the depth of flow would improve fish safety.http://www.pnnl.gov/main/publications/external/technical_reports/PNNL-22236.pdf

References

External links

* Dams in Oregon Hydroelectric power plants in Oregon Buildings and structures in Linn County, Oregon Sweet Home, Oregon United States Army Corps of Engineers dams Dams completed in 1968 Energy infrastructure completed in 1968 1968 establishments in Oregon {{LinnCountyOR-geo-stub

Risk to fish

See also

References

External links