Non-governmental organisations have been protesting about what they see as their exclusion from an international conference in the Swiss capital, Berne, aimed at promoting the use of hydroelectric power worldwide.
The groups are accusing the organisers of Hydro 2000 of failing to pay enough attention to the environmental and social impact of large dam projects. The conference organisers reject the accusations.
The three-day meeting brings together hundreds of delegates from 45 countries, including engineers, researchers, landowners, businessmen and financiers. Their goal is to develop economic, environmental and social strategies that will boost hydroelectric power.
Among the protestors is the Berne Declaration - a Swiss advocacy group whose stated aim is to promote environmentally and socially acceptable hydro development - and the federation of Kurdish organisations in Switzerland.
Peter Bosshard, of the Berne Declaration, says large dams are responsible for flooding some of the most fertile and biologically diverse lands on earth. He says they have forced at least 30 million people from their homes.
"Many large dams are monuments of mismanagement, vested interests and corruption," Bosshard added. He went on to say that projects like the Three Gorges dam in China, and the dams in India's Narmada valley, show that representatives of the dam industry are irresponsible.
At a small demonstration in Berne on Monday, the Social Democrat member of parliament, Ruth-Gaby Vermot, also expressed opposition to the creation of dams that have devastating consequences on people unable to stand up to big business.
"The Ilisu dam in Turkey is a telling example of the destructive impact of large dams," she said.
Vermot added that up to 78,000 people would lose their homes or lands due to the Ilisu reservoir, and that malaria would spread in the region.
Other dams singled out for criticism were Sardar Sarovar and Maheshwar in India, San Roque in the Philippines and Bujagali Falls in Uganda.
The protesters called for work on the dams to be stopped, and for official export credit agencies not to provide any funding for such projects. They urged the authorities all over the world to resolve problems concerning existing dams, before planning new ones in the same country or region.
One of the key messages at the demonstration was that no dam projects should go ahead without the prior free and informed consent of the affected communities.
Organisers of Hydro 2000 dismissed the complaints of the NGOs outright.
"Over the first two days of the three day meeting, we've had sessions dedicated to social aspects and ecological and environmental aspects," Richard Taylor, executive secretary of a group cosponsoring the event - the International Hydropower Association - told swissinfo. "I think that shows a very strong concern and consideration for the industry."
Taylor added that environmental and social working groups had been set up "which are addressing and trying to look at the best mechanisms to minimise the impact of hydropower projects."
swissinfo with agencies