Farhad - The Atlantic Salmon Federation has been involved in a number of dam removal projects that were targeted at least partly for the restoration of salmon spawning habitat.  See their website for links to various information resources pertaining to several projects.  (http://www.asf.ca/dams-and-fish-passage.html)

hope this is of some use.

John

Dams' removal has become a trend in recent years in developed countries such as U.S.A . So far, 850 dams have been demolished in that country. In some 3rd world countries, were "ignorance" abounds, the peoples are told a different story about the "mythical" advantages of dams besides production of electricity (i.e. they are misled).

The attached reference talks about the world's largest dam removal & presents some real advantages of such project. My regards.

http://news.nationalgeographic.com/news/2014/08/140826-elwha-river-dam-removal-salmon-science-olympic/

In Fujian Province, China, I have seen no sign of any dam removal action. Best regards.

Dear John,

Thanks for your information.

Dear Pei Zhou,

The worst thing in Iran is annual improve in the amount of dam construction projects in this country. This have made serious hydrological problems and make them worse.

Dear Nizar,

Thanks for your useful information. Unfortunately, one of those countries that you mentioned is Iran. We are changing the natural water cycle in our watersheds by dams. Do you have the reference for 850 number of dam removal projects in USA?

Best wishes.

Nizar/Farhad-

There have actually been over 1000 dams removed in the US.  The US Geological Survey has created a database of scientific literature and research in the field. See:

https://www.sciencebase.gov/catalog/item/55071bf9e4b02e76d757c076

Dear @ Farhad, I got the number 850 from the reference I gave in my previous contribution (relatively old one). I think the figure given by dear @ John Cadham of >1,000 dams may be more accurate. My regards.

Thanks for your useful information.