1. What I would propose is that the dam. The dam was built, starting from the need to tackle the shortage of water and energy to help solve flooding drought by storing water during the flood. And the release of water for domestic and agricultural water shortages during the season. Help manage the use of water thoroughly. The process to build dams along the diagonal line of the ridge as the flow of the main river. And the need to drill in certain areas to let the water drain out of the way for a dam on the amount of water too. Dams require knowledge in many areas, such as knowledge of geology. In engineering, irrigation, etc., to build out completely.
2. The challenge of this process is The dam has a huge impact on the environment. The dam will create a valley with a river flowing through it. And built across the river To allow water to accumulate in areas above the dam area will be flooded. Lack of soil fertility The dam is a vast area. Some areas may be in the area of wildlife sanctuaries. As a result, resources Nature in the area. Corruption can not be used to advantage. Vegetation in the area is dying. Some plants, which may be rare. Forest conversion into a flooded area. Make some wildlife to flee the water before it died. Some homeless It also makes changes to the aquatic ecosystem. From an ecological water flow became a backwater. The creatures living in the water ecosystem is reduced. It also affects the migration of many fish species. During the drill, which is very long. Drilling within the flow of air at least. Dust and smoke more Impact on workers and work processes.