The Analysis of Dam Induced Risk at its Upstream and Downstream Side

hills, which are geographically rich in flora and fauna. As shelter, food, water are easily available in such location, historically, these have been sites for human settlements. Before constructing of a dam, the areas has to be first cleared of human settlements and vegetation, an enormous intrusion into and invasion of the human, aquatic, and eco-system of the entire region. With the construction of a barrier such as a dam, the water is collected in a huge lake or reservoir that results in submersion of local surrounding area in upstream. Along with that it also decreases the fertility of soil due to regular soil salinity. Since dams are long term projects, this also result in the increase in the flood level of river basin due to deposition of silt carried by the river. This also increases the risk of flood in river basin area. There is also chance of landslide near the water reservoir due to slope failure along the edges of the reservoir. Standing on a dam, and looking upstream and downstream presents two divergent scenarios. Upstream, the dammed up river is full of water, standing in a static lake while downstream, the river is reduced to a few streams, hungry for water. In many cases, due to low water levels downstream, the channel shrinks and fertile river islands are created, providing attractive settings for new settlements. The settlers are often unaware of the risks of living in such fragile environments, which are vulnerable to inundation at times of excessive rainfall when the discharge from the dam cannot be regulated to protect these settlements downstream. This causes tremendous damages to human life and property, causing untold suffering.