Dams vs MegaDams vs Desalination plants

Question 1

Dams

Answer 1

Used for storage and flood control

Question 2

Mega Dams

Answer 2

Nearly 60% of the world’s major rivers have large dams of which the Aswan, Hoover and 3 Gorges are amongst the largest

Mega dams are significantly larger than typical dams, with height and power generation capacity being key distinguishing factors.

Mega dams often prioritise electricity generation, irrigation, or water supply for large populations

Have issues aside of the huge economical costs of construction
Dams alter ecosystems - downstream ecosystems rely on water and sediment, both of which are held back by big dams, making downstream land less fertile

Dams displace people, communities and destroy cultural heritage

Flooding of the reservoir submerges land and destroys plants and animals

Dams reduce water quality and waste water - large surface areas of reservoirs increase rates of evapotranspiration and trap sediment and agricultural runoff, increasing rates of eutrophication and vector diseases

Question 3

Desalination plants

Answer 3

Extracts the salt from seawater to enable it to be used for drinking and irrigation

Expensive, salt waste can damage marine ecosystems and the process uses large amounts of energy

As the price of freshwater increases, some countries will look to the sea for water supplies

Dubai has already done this, as has Kuwait and Saudi Arabia

Although it is a sustainable process, it is considered a hard engineered process due to the inputs of technology and energy and it has an ecological impact on marine life