Ever since the dams came into existence we have been debating about them. But all these discussions don’t result in any productive conclusion.
In the year 2013, Uttarakhand experienced a massive devastation. Cloudburst followed by flood and landslide took toll of large number of life and property. The debris blocked up the rivers, causing major overflow. Houses were washed away, trees uprooted, roads and bridges were wrecked and thousands of people lost their lives. It been more than two years and the people of Uttarakhand are still struggling to bring their life back on track. A report was prepared on this incident and most of them held the construction of dams responsible for such a great loss. The body’s report said, “The problem with the dams is their location in a high or very high biodiversity value area, some of them at elevations above 2,200-2,500 meters. These altitudes come in the paraglacial and glacial zones and in these zones, the rivers are capable of mobilizing tremendous amounts of sediments, under intense rainfall conditions, from the moraine left behind in the past by receding glaciers. In such situations, they cause havoc in the vicinity of dams as witnessed at the Vishnuprayag barrage site and below during the June 2013 disaster.” Here are some ways in which dams have affected us.
Contamination of Water: Flowing water when in a reservoir goes through a number of chemicals, thermal and physical changes which contaminate it. Water released from a dam is usually cooler in summer and warmer in winter than river water, while water from outlets near the top of a reservoir will tend to be warmer than river water all year round. Change in the temperature of the river affects the amount of dissolved oxygen and suspended solids it contains.
Affect on Aquatic life: Smaller fishes may be pulled into the intakes and get killed. Even riverine fish adapted to fast current may be lost. The number of fish-eating organisms will be reduced. This leads to an imbalanced life cycle in the river. Diseases and parasite infestation and increased mortality too will find their way to the dam water. The dams also obstruct the route of the long and mid-distance migratory fishes.
Unemployment: A number of communities around the river belt are fishermen. These people are totally dependent on fishing for their livelihood. Reduction of riverine fisheries will influence the life of most of these fishermen.
Sedimentation: When a river is stilled behind a dam, the sediments it contains sink to the bottom of the reservoir. At one point of time, the dam is full of sediments and does not even fulfill its purpose. The water too loses its natural minerals.
Dislocation: When Tehri Dam was constructed it dislocated more than 100,000 people from the area has led to prolonged legal battles over relocation rights. The people living around the dam construction area lose their homes and are not even compensated with one for long. As a result, they have nowhere else to go.
Deforestation: For the construction of dam the forest around the area needs to be cut down. The earth is already going through a lot of ecological changes. Afforestation is the need of the hour and cutting down the trees will only affect the environment negatively.
Dams have a negative impact on the ecosystem. Problems such as soil erosion, the effect on marine life, interruption of natural cycles, deforestation, and displacement of people are some of the major issues that come up when a dam is built. Ever since the dams came into existence we have been debating about them. But all these discussions don’t result in any productive conclusion. It high time we take up this issue seriously and do something about it for a better and brighter future.