To Breach or Not
To Breach or Not to Breach

The 4 hydroelectric dams on the lower snake river. This has been a question for about 10 years now.

The map below shows the location of these 4 dams:

The image below is the Lower Granite Dam:

Contrary to popular perception, Dam breaching doesn't mean a catastrophic explosion of the concrete dam. Much as one could sell tickets to an event like that, dam breaching on the Snake River Dams is much more benign and involves removing the earthern part of the dam (which is on the left side of the image above)>

Independent of your own personal feelings on the matter, it is generally useful to construct a Pro/Con Table that centers on this issue. For example,

Arguments For:

  • restore Salmon runs
  • restore river to its more natural state
  • create short term jobs (sledgehammer crew).

Arguments Against:

  • Loss of Power
  • Loss of flood control
  • Loss of Irrigation
  • Loss of River Navigation
  • Toxic Waste movement down the river

Notice that the listed items under Aguments against are quite obvious and really don't require justification. All of these things would happen, it just matters to which degree they would happen and this is very difficult to model.

The arguments in the Pro section are more speculative as its unclear if dam breaching would accomplish these goals. Certainly in the long term (50 years) this would happen, but how long would it take for the river to resume its natural state? Moreover, refering to the Map above, if the primary goal is to restore Salmon runs - then shouldn't the 4 dams on the Columbia river, below where the Snake enters it, also be breached?

Also, before one actually breaches, shouldn't one properly assess the current efforts at helping restore salmon runs?

Current Status of Salmon Migration and Survial Rates as measured by the National Marine Fisheries Service

What is understood less is the indirect or delayed mortality of juvenile fish that may occur after they have passed Bonneville Dam. That mortality may have been caused by passing in-river through the hydrosystem, the series of eight dams and reservoirs from Lower Granite Dam to Bonneville Dam or from transportation of fish.

The most striking number in this measure of survival rates, is that, under the current system of transport, 80% of the juvenile salmon (those are the ones heade downstream to the Pacific Ocean) survive the transit. Thus, in principle, removing the 4 snake river dams can only add 20% to this survival rate and there are still 4 bigger dams for the juveniles to face.

For the record, here is what the 4 dams in question look like:


Ice Harbor Dam


Lower Monument Dam


Little Goose Dam


Lower Granite Dam

Another complex, often emotional issue, in which there is very little science to guide us:

Cost/Benefit Analysis is difficult and often driven by hidden agendas Save Fish vs. Lose of Jobs ?

Costs of dam breaching are difficult to estimate but are in the range of $1 billion and up.

Will it work?

Current Socio-Economic Benefits of these 4 Dams:


Relevant other sources on this issue

Four Alternatives Identified:

Some possible undesireable consequences from Dam Breaching:

Okay Then, let's truly end the hyprocrisy and breach all the dams in the Columbia river system

What are the options for replacement power?