5. Human causes for water deficits: Aral sea and Ogallala aquifer …
5. Human causes for water deficits: Aral sea and Ogallala aquifer
Ogallala aquifer, USA
the present rate of depletion could see the aquifer dry by 2020.
High and rising costs of pumping water from depths as great as 6000 feet is discouraging farmers from using irrigated farming for much longer.
- $32 billion of agriculture production a year. mostly wheat, corn, cotton, and 40% of the countries grain fed beef.
- if all farmers used water conservation measures, depletion of the aquifer would be presented. However, this is not likely to happen
aquifer depleting eight times faster than its natural recharge rate.
Uzbekistan extracts more water than it is generating
In the last 60 years it is now
10% of its original size
due to expansion of agriculture under Soviet under in the 1960s.
Dam built between the large and small Aral seas that funnel water into the Aral.
Tighter environmental legislation
More efficient irrigation system funded by UK and World Bank
anthropogenic led climate change decreased precipitation by 10%
and increased local summer temperatures by 4 degrees, increasing evaporation rates
Great Artesian Basin, Australia
$1.6 billion a year on farming, mining and tourism.
31,000 megalitres of basin water each year, however this contributes to greenhouse gas emissions,
releasing 330,000 tonnes of CO2 annually.
covers 20% of Australia
90% of the water that has been extracted so far has been wasted.
Local human pressures on water supplies
household water consumption
Drinking water for exponentially growing populations.
Uganda: 55 litres
USA: 450 litres
UK: 150 litres
Agriculture, food and drink production
largest user of water in the world
hit by a bottling plant for Coca Cola in the early 2000s. 6 wells were dug, tapping into their groundwater store, now there are severe water shortages
Growth in emerging economies has increased industrial activity worldwide, putting extra pressure on water supplies.
World trade on industrial products has risen from
$2 trillion in 1980 to $18 trillion in 2011,
according to the World Trade Organisation Statistics
at least 30 feet of saturated thickness is necessary of large scale irrigation.