If dam Must be a problem and various effects on people in the area. And have lost a lot of forest resources. In contrast, if the dam rapids dance it would be useful, not less.
If the dam is causing the problem and the impact on the people in the area and lots of forest resources must be lost, but on the contrary, if it beats the rapids dam is not less useful.
If there is a problem and the impact the dam must be different and must be given to the man in the loss of forest resources, but on the contrary, if the dam will have a shot to dance is not less useful.