Hydropower

Myth Busters about dams and fish

As the debate continues on fish programs related to the hydrosystem, sometimes it’s difficult to separate fact from fiction.  Here are some myth busters from the Public Power Council.

 

Myth 1:  Spilling water over dams creates the safest route of passage for fish.

Facts:  

  • Fish navigating through spill water is not natural and has risks.
  • More water spilled does not always lead to higher fish survival
  • Increased water speed does not equal increased fish survival.
  • High water spill volumes can make it harder for adult salmon migrating upstream.

 

Myth 2: Salmon and steelhead will recover by removing the four Lower Snake River Dams.

Facts:

  • Removal of the dams does not guarantee increased fish survival.  Current juvenile fish passage survival rates are at or above 95% at all four dams.
  • The dams only affect 4 out 13 Endangered Species Act listed salmon and steelhead stocks in the Columbia River basin.
  • Dams impact only 10% of the historic fall Chinook spawning habitat in the Snake River; other species were less affected.  Removal will not significantly improve access to historic spawning areas.
  • The removal of the dams would have tremendous negative impact on our economy and environment by eliminating about 1,020 average megawatts of clean, carbon-free energy, increasing green house gasses by 4.4M tons per year, reducing navigation and irrigation capabilities.

 

Myth 3: Lost generation costs are not real

Facts:

  • Spill and flow augmentation reduce the amount of water available to generate power which reduces BPA’s ability to meet contractual obligations and requires them to purchase replacement power.  It also reduces BPA’s ability to sell surplus power and reduce rates.
  • The Northwest Power Act requires lost generations costs to be identified in order to do a cost benefit analysis of fish and wildlife mitigation actions.
  • Cost-based rates are increased by both the additional costs of replacement power and the loss of a source of power revenue.
  • To achieve an honest cost-benefit evaluation, estimates of specific biological benefit of hydro system mitigation actions are needed. 
  • The costs associated with lost generation are legitimate and appropriate to be included in cost and rate impact evaluations.  Quantifying the impact o f lost generation is needed in order to make informed decisions about the relative cost-effectiveness of measures.

Myth 4: The federal hydro system is the greatest source of mortality for salmon in the Columbia River.

Facts:

  • The quality of freshwater habitat is a primary factor affecting the survival of salmon and steelhead in the Columbia River basin.
  • Ocean conditions are a significant factor affecting the return of adult salmon and steelhead. Ocean researchers have found that water temperature, food availability and the number of predators that eat juvenile salmon have a much greater effect on salmon and steelhead stocks than the federal dams on the Columbia River. 

Myth 5: Little has been done to improve fish survival past the federal dams.

  • Significant improvements have been made, and continue to be made, at federal dams to enhance salmon and steelhead survival. From the early 1900’s through 2006, more than $2.5 billion was invested to develop and install new and improved fish passage facilities at the federal dams on the lower Columbia and Snake Rivers.  Screens have been installed in front of turbines to keep juvenile fish from entering.  Bypass systems have been built to collect juvenile fish and route them around dams.  “Fish slides” and other surface bypass systems that pass fish safely over dams have been installed at the dams. 
  • Improvements to fish and wildlife habitat and hatchery programs is ongoing.  Ratepayers have funded more than $1.8 billion for building and operating hatcheries, improving fish and wildlife habitat such as spawning and rearing habitat in tributaries and protecting wildlife habitat for waterfowl and large mammals.
  • Ratepayers will fund nearly $1 billion a year in fish and wildlife mitigation programs beginning in 2010-2011.  The federal biological opinion for the federal hydro system requires continued improvements for fish survival at the dams and fish habitat in the Columbia River tributaries, including spill, flow augmentation, turbine operations, fish collections and transportation, hatcheries and funds for the Northwest Power and Conservation Council Fish and Wildlife Program.