Overview on Dams

The advantage of dams lies in their ability to regulate water flow, prevent floods, and store water, thus ensuring a stable water supply for human needs and economic activities. The dams are large barrier-like constructions built on flowing water systems like rivers and streams. The main benefit of dam construction is water storage. When the water level upstream exceeds the dam capacity, floodgates will be opened slightly. This will help in a controlled flow. In this article, we will read about dams, the advantages of dams, their importance for human benefits, and their disadvantages.

What are Dams?

Dams are also called dykes or levees. They are large structures built on flowing water like streams and rivers to stop water flow. The advantages of dams are conserving water and generating electricity. The barriers constructed on the flowing water system create a large reservoir upstream. This stored water in the reservoir can be used for long-term purposes like domestic applications and industrial purposes.

Dams can be built from different materials. Ancient dam builders used natural materials such as rocks or clay. Modern-day dam builders often use concrete. Dams control floods and save thousands of lives. However, there are some disadvantages of dams as well as it can cause a lot of environmental damage. Dams can block the natural flow of water, which can disrupt the ecosystem.

Types of Dams

The dams constructed in recent days are of two types.

• Concrete dams: These are also called masonry dams and block streams running through narrow gorges. Nagarjuna Sagar is a classic example of a concrete dam.
• Embankment dams: These dams are built on broad river systems. Tehri dam is an example of an embankment dam.

Uses of Dams

Some major usage of dams are –

• Water Supply: Stored water in the dam is used to provide water to industrial, municipal and residential sites. It also helps in supporting the ecosystem and agriculture by releasing water during drought.
• Electrical generation: Dams work as a source of hydroelectric power, it convert the potential energy which is stored in water into electrical energy and contributes to energy production.
• Flood control: Dams help in controlling floods by collecting and holding water during floods. It also helps in regulating the level of water.
• Erosion Control: Helps stabilize riverbanks and control soil erosion in downstream areas.
• Biodiversity Conservation: Creates habitats that can support diverse fish, bird, and wildlife populations.

Importance of Dams for Human Benefits

The Importance of Dams for Human Benefits are:

• The benefit of dams is that they supply water for irrigation, industry, and household use.
• They also offer river navigation and hydroelectric power generation.
• Hydropower generation contributes to the reduction of greenhouse gas emissions and is a dependable source of electricity.
• Dam reservoirs offer recreational opportunities and attract tourists.
• Properly managed dams contribute to environmental preservation and ecosystem protection.
• Stored water in reservoirs helps mitigate the impacts of drought on agriculture and water supplies.
• Dams reduce downstream sedimentation, preserving water quality and ecosystems.

Advantages of Dams

The benefit of dams is that it can store water in massive quantities ranging up to trillions of gallons. The exact amount of water a dam can store will depend on the reservoir capacity. This is relative to the length, and depth of the reservoir. Storing water in such huge quantities offers many advantages for humans such as:

• Water stored in the dam reservoirs can be used for irrigation and support agriculture across several miles of distance.
• Hydroelectric power generation is one of the main advantages of dams. The water stored in the reservoir is allowed to fall on large turbines. The potential energy of stored water is converted to kinetic energy and further into electrical energy. Hydroelectric power is a renewable form of energy and accounts for 12.5% of total power generation in India.
• Hydroelectricity generation does not produce any harmful greenhouse gases. For this reason, hydroelectric power is environmentally friendly. Further, water is a renewable source, unlike coal or petroleum. Hence, relying on renewable resources is better for future generations.
• The reservoir holds large quantities of water that can be a freshwater source for human usage. Dams serve as a continued source of water in dry periods especially, in tropical countries like India, where the rainfall is seasonal and limited. Irrigated water can support agricultural fields that are at a far distance from the dam area and those with limited groundwater levels.
• Dams have controllable floodgates. These control the water level in the upstream area.
• The reservoirs are a centre for recreation and tourism activities. Nowadays, many tourist activities like boating, fishing, bird watching etc. Idukki Dam, Nagarjuna Sagar Dam and Bhakra Nangal Dam are some famous dams in India preferred as tourist and recreation spots.
• In addition, they are sites for biodiversity where various freshwater aquatic species like fishes and allied bird species depend and develop. Altogether, dams form large freshwater ecosystems.
• Dams are constructed on fast-flowing water and can prevent floods in plains saving millions of lives.
• Dams also prevent soil erosion and protect fertile sediments from washing out to ocean waste fully.
• Dams also offer navigation facilities where human and material transport can happen with the help of boats.

Disadvantages of Dams

Constructing dams has some severe negative consequences on the environment.

• Dam construction requires large areas of land because of which farmers and social life associated with the land will be disturbed.
• Besides social life, the greenery in the construction area will be disturbed which has a great impact on the environment.
• Dams are huge structures and their construction would need digging out deep layers of earth disturbing the topography.
• They can also cause disturbance in the migratory patterns of birds and fishes by disturbing their natural habitats.
• Above all, constructing dams would need a large amount of public money.
• Debris and sediment buildup in the reservoir can reduce the water-holding capacity.
• Dam failure is the biggest hazard. Design failure or unexpected forces causing dam failure can lead to severe damage to the human population and living species thriving in the dam locality.

Conclusion: Dams

Dams are huge constructions on flowing water systems like rivers. There are plenty of advantages of dams to humans including hydroelectric power. Dams are important for society because they provide water for people to drink and use, protection from floods, hydroelectric power, irrigation water to grow food, a pleasant recreation area, and enhanced environment. Dams are also involved in river navigation. Like any other man-made structure, they also have some negative impact on the environment. The disadvantage of dams include displacement of communities due to submergence of land , habitat loss, and disruption of fish migration patterns.

FAQs on Dams

Name Some Dams in India

Tehri Dam in Uttarakhand, Bhakra Dam in Himachal Pradesh, Mettur Dam in Tamil Nadu, and Hirakud Dam in Odisha are some of the dams in India.

What are the Advantages of a Dam?

Dams prevent floods, store excess water for various uses including domestic, industrial, and agricultural needs, and generate electricity for human and industrial consumption.

What are the Advantages and Disadvantages of Dams Class 8?

The advantages of building dams are to provide a renewable source of energy through hydropower generation and control flooding by regulating water flow downstream. The disadvantage include habitat loss and displacement of communities due to submergence of land.

What are the Benefits of Dams to the Environment?

The upstream reservoir at dams supports aquatic static ecosystems where fishes, turtles, reptiles and birds can grow. Hydroelectricity generation at dams has zero effect on the environment. It is a renewable source and does not generate greenhouse gases.

What are the Harmful Effects of Dams on the Environment?

Dam construction requires the evacuation of fertile farmlands and the dislocation of the human population. It also disturbs the natural river flow disturbing migratory fishes and birds by disturbing their nesting and spawning grounds.

What is the Importance of Dams in Human Life?

A dam constructed once can serve human benefits for at least a hundred years. Dams are a source of water for industrial and agricultural needs. They are a source of renewable hydroelectric power which has zero negative impact on the environment.

Are Dams Useful to Humans?

Dams are useful to humans in many ways. They provide water for human domestic, industrial and agricultural needs. The water can be transferred to arid and semi-arid areas across miles of distances.

What are the 5 Disadvantages of Dams?

Habitat loss, displacement of communities, risk of dam failure, impact on fisheries, and siltation