✅ 3.2.5.3 RESOURCE SECURITY - Water Security Flashcards
Agricultural uses of water
Farming - Farms use water to irrigate crops and raise livestock.
Industrial uses of water
Steam generation, washing, cooling
Often creates wastewater, has to be recycled
What % of water withdrawals are for domestic use
11%
Higher in HICs w/ high rainfall like UK
Low in most other countries, especially LICs
What is India’s agricultural water use
Largest in the world at 700 billion m^3 / year
Growing rapidly, doubling from 1975 to 2010
What % of freshwater withdrawals are for agriculture globally, in HICs and LICs
70% globally
90% for LICs
41% HICs
Which countries all irrigate over half of their agricultural land
Pakistan, Bangladesh, South Korea
(warmer poorer countries who therefore must rely on agriculture, so need to abstract more water for irrigation)
What % of total water withdrawals are for industrial purposes?
19%
What % of total water withdrawals are for industrial purposes in LICs?
2% (is much greater usually in HICs)
What is the US’s industrial water use
300 billion m^3 / year
Largest in the world
China 2nd largest at 140
Which country has the highest per capita water demand
USA - 6.8 tons / day
How many river basins in the world are transboundary
276
What is an artesian aquifer?
an aquifer between impermeable rock
therefore water doesn’t escape
is recharged where it makes contact with the surface
Water stress
When demand for water exceeds supply, or when water is not of high enough quality to use, places experience water stress.
Under 1,700 m^3 pp annually
What level of water per person is water scarcity
What countries have water scarcity
Under 1,000 m^3 pp annually
South Africa, Iraq
What level of water pp is absolute water scarcity
What regions have absolute water scarcity
Under 500 m^3 pp annually
North Africa
What level of water pp is Physical water scarcity
What regions have physical water scarcity
Less than 500mm of rainfall a year
Middle East, N Africa
What is economic water scarcity
When a pop. does not have the monetary means to access enough water
South America, South Africa
What does the UN define water security as?
The capacity of a nation to safeguard sustainable access to adequate quantities of acceptable quality water
Physical factors which affect water supply
Climate
Geology
Drainage
How does geology in Thames Basin affect water supply
Chalk in the Thames Basin acts as an aquifer, provides base flow
How does climate affect water supply in Thames Basin
690mm / year (UK average is 900mm)
Thames basin classed as suffering severe water stress.
During winter groundwater stores are replenished
Not much water available for natural environment
How does drainage in Thames Basin affect water supply
Thames Basin supplies 80% of London
Majority of this is from ground water from acquifers
Impact of unclean water on children
340,000 children under 5 die every year from unsafe water use
How many use a drinking water source contaminated by faeces
2 billion
How many lack access to basic drinking-water services
785 million
10% of the population
How does water contribute to public health
SDG 6 aims for global accessible clean water as it is essential
Access to clean water means cleaner facilties, less spread of diseases like Cholera
Safety for women and children who sometimes have to travel far to collect water in some poorer places
Clean water means safter crops, clean waterin irrigation used
Lack of accessible clean supply means using unclean surface water supplies
Strategies to increase water supply
Desalination
River Catchment Scheme, e.g Dams
Transfer scheme
Boreholes, Groundwater
Sources of water
Surface water
underground water
seawater
What is a borehole
Drilling down nto ground to a borehole, to make a well, to access groundwater supplies
Pros of boreholes
Groundwater is available year round
Cons of boreholes
Can deplete groundwater stores faster than they recover
Can cause subsistence
Water has to be cleaned
Salt water intrusion intogroundwater as aquifers recharge
Rivers dry up
What does desalination involve
Obtaining potable water from seawater
Via reverse osmosis (through a partially permeable membrane)
Distillation (extracts water vapour, condenses it)
What are cons of desalination
Expensive- plants cost up to $2.9 billion
Can damage fisheries as ocean water intake pipes suck in and kill marine life
What are pros of desalination
Can provide supply to arid, hot countries
Effective
Which countries use desalination most
Saudi Arabia (70% of supply from desalination)
UAE
USA
Israel
Often drought hit wealthy countries
Example of desalination in the UK
Thames Water’s desalination plant in East London
Supplies to 400,000 households
From 180 million litres of Thames River water per day
What does storage by reservoir involve?
Dams built to trap and store surplus winter rainfall or regulate river flow
E.g High Aswan Dam
Usually built by flooding a valley and building wall
Pros of reservoirs
Flood control, prevents flood downstream
Stored water supply
Can be used for HEP like High Aswan Dam or more like fishing
But is expensive
Environmental impacts of reservoirs
-Sedimentation/siltation- deposited in reservoir, reduces capacity and increases erosion rates (e.g High Aswan Dam to Mediterranean)
-Creates higher wind speed and humidity downstream
-Flooding behind the dam removes habitat and interrupts fish migration
Features of the Kiedler Water Reservoir
UK
Cost £185 mllion to built
River Tees, Tyne
1.5 million trees cut down to make
attracts 300,000 tourists a year
What is a water transfer scheme
Transporting water via pipelines from a place of water surpluys to water deficit
Can be used for agriculture, e.g water for irrigation used in Pakistan from Indus Basin
Pros of water transfer scheme
Localised drought can be remeidied quickly
Habitats protected
Addresses rain disparity
Cons of water transfer scheme
Water expenisve to pump
Requires development of reservoirs to store incoming water
Water transfer scheme in UK
From North-Wales - 400mm rainfall a year
To East Anglia - 55mm
Popualtion is much higher in East Anglia
Water transfer scheme in China
Largest transfer scheme between river basins
South to North (drier)
From Yangtze River Basin to north, Beijing, which is experincing water shortage
How much of Beijing does the China water transfer scheme supply
2/3 of Beijing’s tap water
How much water does the China water transfer scheme supply?
Travels how many km?
Up to 25 billion tonnes of water/ year
1,400 km
Increasing water supply: what is Singapore’s 4 tap strategy
To increase supply, 4 supplies of water established
- Water from Malaysia (some dependency)
- NEWater scheme (recycled water)
- Water desalination
- Local catchments (like storm runoff) & reservoirs
Why does Singapore need its 4 tap strategy
Densely populated, growing population
Limited land to collect water from, despite its high rainfall (2400mm/ year) due to lack of big rivers and lakes
Vulnerable to droughts (which also affects neigbours)
How densley populated is Singapore
5 million in just 700km^2
Singapore annual rainfall
2400mm
How available is water in Singapore
ranked 170 of 193 for natural water availability by the UN
Managing water consumption: domestic use
Installing domestic water meters - reduce water bill by an average of 10 to 15 % , but only 43% of houses have them despite them being obligatory in UK
Installing low-flush toilets- toilets use 30% of water in a home
Collecting rainwater, showers not baths - behaviour
Managing water consumption: industrial or commercial use
Buildings now designed to use rainwater in toilets
Managing water consumption: agricultural use
Micro-irrigation; for example micro-sprayers which spray fine mist- less waste
Using mulch (compost around plant) to retain water
Watering in early morning to reduce evaporation losses
The Aswan High Dam features
110 m high, 4 km long
Nile, Southern Egypt
Reservoir behind it is Lake Nasser which stores 132 km³ of water
Why was The Aswan High Dam built?
HEP
Flood regulation (yearly floods would occur which could wipe out crops)
To provide storage of water for agriculture (irrigation)
What shows that the Aswan High Dam is ineffective
The creation of the Grand Ethiopian Dam
Socio-Economic impacts of water supply scheme: High Aswan Dam
Lake Nasser sometimes floods - displaces people
Lake Nasser creates more land for farming due to supply for irrigation
Lake Nasser has created a fishing industry
HEP supply to Egypt
Removes fertile sediment for downstream farmers, so they have to buy fertiliser which is expensive and can cause environmental damage
1 million Africans caught Malaria due to their proximity to the reservoir due to its salty, low-energy water
How many were displaced when Lake Nasser flooded Nubia?
100,000
How many fish are caught each year from Lake Nasser in the fishing industry?
25,000 tonnes per year
What is The Aswan High Dam’s HEP capacity per year?
How much of Egypt’s supply is from it?
10 billion KWh per year
Was ½ but now only 10%
Environmental impacts of water supply scheme: High Aswan Dam
-Sediment trapped by the dam has increased erosion rates downstream in the Mediterranean
-Sediment trapped in the dam is slowly reducing water storage space, occupying 32 km³ (although will take 900 years to fill completely)
-Fertile soil trapped from travelling downstream has reduced sardine populations by half, off the Egyptian coast
-Continuous irrigation of farmland means the water is not annually flushed out, so the soils get saltier and therefore less fertile over time
-Increased water clarity, meaning more sunlight can penetrate the water, and use of fertilisers, has caused the soil quality to fall due to the increased presence of algae, meaning the water must be treated more, which is expensive
What does sustainable water management aim to achieve?
A greater long term balance between supply and demand while minimising environmental impacts
What is virtual water trade
The water used in the production process of a product is called the virtual water.
Virtual water trade is the idea that when commodities are exchanged, so is virtual water.
Idea developed to understand how water-scarce countries could provide products without depleting their water resources.
What regions are net-importers in the virtual water trade?
The Middle East
More water enters the Middle East as “virtual water” than physically enters such as through the Nile, thereby relieving its water sources
How much water is used to produce 1 tonne of beef?
15,400 m³
How much water is used to produce 1 tonne of wheat?
1,300 m³
What are weaknesses of the virtual water trade concept?
It assumes the water used is wasted
It doesn’t account for water that is recycled/ reused
What is Neo-Malthusianism
The advocacy of human planning to ensure resources and environmental integrity are available for current and future human populations,
How can land use increase sustainable management of water?
In urban areas, more runoff into short-term store river
But with more vegetated and permeable land, runoff is reduced and groundwater stores are replenished, a much longer store of water
How can recycling water increase sustainable management of water?
Through extensive sewage treatment, can be recycled
90% of water used in London is recycled
In less developed countries, like in North Africa, 82% is not recycled- room for improvement
Greywater can be recycled for purposes other than drinking such as irrigation
What is greywater
Water that has been used in washing or cleaning, but has not come into contact with faecal matter (blackwater)
How can leakage control increase sustainable management of water?
Repairs of pipes will reduce water leaks
3 billion litres of water is lost per day in the UK due to leaky pipes
How can groundwater management increase sustainable management of water?
Aquifers can be recharged methods such as rainwater harvesting into recharge wells, which is used widely in Australia, as these stores can be used in times of water stress
keep going!
Where is the Aral Sea
The border of Kazakhstan and Uzbekistan
What problems have occurred in the Aral Sea?
By the 2000s it was 10% of its 1960s size
and water very saline, 3 grams of salt / litre
Partly due to highly intensive water usage in cotton production and abstraction
How were the issues in the Aral Sea resolved
2005 Kok-Aral Dam built
Increased water levels by 12 metres, now only a further 6 metres away from being used again
Salinity levels normal again
However, long term recovery still on going
Where does the Colorado River run?
From SW USA to Gulf of California
2,300 km
What problems does the Colorado River face?
In a 16 year drought
Demand is rising - Colorado’s population will nearly double by 2050, plus it flows through dry areas like Las Vegas
How were the issues in the Colorado River dealt with?
Treaties in 1948 to allocate share of water
But the River has since decreased in flow due to so many withdrawals/ shareholder demands
Where is Cochabamba?
City in Bolivia
What was the water conflict in Cochabamba?
1998 - IMF gave loan to Bolivia but they had to privatise water industry
Aguas Del Tunari buys exclusive right to Cochabamba’s water system
2000 - Cochabamba protesters shut down the city for four days, going on strike as Aguas del Tunari’s rate hikes have tripled their water bills, riots develop
La Coordinadora holds an unofficial referendum in which an overwhelming majority - 96% of 50,000 voters -disapproves of water privatisation and Aguas del Tunari’s water contract
La Coordinadora signs an agreement with the Bolivian government that guarantees the withdrawal of Aguas del Tunari, grants control of Cochabamba’s water to La Coordinadora, assures the release of detained protesters, and promises the repeal of water privatisation legislation
