Water key facts and case studies

71%

96.5%+

70%

29%

3,600 years

15,000 years

2 weeks to 10 years

>90%

156.2

1,154mm

World’s 3rd largest watershed

Drainage basin for 41% of the USA

• Extends across an area double the size of mainland France

• Holds more than 30,000km² water

• Water has accumulated over the last 1,000,000 years

• Supports Tunisia, Algeria, Libya etc

• Estimated recharge is 40% of withdrawals

• 6,308km long and has a drainage basin of 6 million km²

• Major influences are rainforest climate, seasonal precipitation and high EVT

• Peak discharge in April, May and the lowest discharge is September

• Linked to wet and dry seasons and snowmelt from the Andes

• Human influences - large dams for cities and HEP

• 3,540km long and drainage basin of 850,000km²

• Tundra climate and flows through a mountain range

• Peak discharge May, June with a dramatic increase due to snowmelt

• Low from December to May due to frozen precipitation - very large seasonal variability

• Few human influences but a little HEP

• Regime changed significantly by the construction of the Aswan Dam in 1970

• River flow reduced by 65% and became regulated between seasons so flood peaks in September were greatly reduced

• Flashy hydrograph - short lag time with a high peak discharge - flash flood

• Shale rock - less permeable

• Many tributaries mean at Austwick - high drainage basin

• Circular drainage basin

• Small amount of woodland - less interception

• Subdued hydrograph

• No tributaries

• Elongated drainage basin

• Large woodland around the stream just before Clapham - interception, absorption, slows down

• Gritstone and sandstone and limestone - more permeable

• Artificial lake - more surface storage

20% in the last 50 years

75% which is reduced to 25% when forest is cleared

80%

10%

65 million+

York, Manchester, Leeds due to dense populations and a high, quick peak discharge

6.1 million km²

Largest drainage basin in the world

7: Brazil, Bolivia, Peru, Colombia, Ecuador, Venezuela, Guyana

15%

• Example of an agreement between countries to protect the Amazon

• Signed by the 7 drainage basin countries and Suriname

• Emphasise the need to improve the QoL of Amazonian people and preserve the natural environment as economic development takes place

Acts as a vapour sink for moisture coming in from the Atlantic - humid air produces precipitation and convective clouds

6 days per decade

Sandy - 3-12 mm/hr

Less permeable clay - 0-4 mm/hr

Forests - 50 mm/hr

Pasture 13-23 mm/hr

$290 million on the Pacific coast of South America in fisheries

10%

$2000 million loss in agricultural production

5 to 8 years

• Manaus

• HEP - Baseload compliancy helps industry

• Reduces natural variability in the river regime

• No flooding

• Destroys wetlands

80% of average January rainfall fell in 4 days

3+ months with less than 50% of average rain

38%

This land area has 70% of the global population

1997

1998 was the strongest ever La Nina

10%

• Poverty and civil war drove people onto marginal land

• Increased rural population increased pressure for food

• Acts as a positive feedback loop enhancing impacts of drought

• Obstructions to pastoral migration and encroachment of farmlands on grazing areas impacted the socio-economic conditions of nomadic communities

• Development of cotton growing on farms reduced grazing areas

• 1999/2000 Ethiopia and Eritrean famine/drought

10 million

85%

• 2006

• Affected more than 50% farmlands, including an area that provides 50% of agriculture

• River Murray had been overextracted

• High per capita consumption of water

• Many farms rely on irrigation

• Low, highly variable rain

• Droughts vary massively

• Many droughts link to El Nino

• Since 1970s, the East has become drier

30%

• Anthropogenic climate change

• Lack of resources for aid organisations

• Not enough medical camps

• Government slow to act

• Nearly 70% of Pakistan’s population worked in the agricultural sector and so lived close to the rivers for irrigation

• Rural communities flooded so people lost homes and livelihoods

• Urban population poorer than rural so Karachi was highly affected as water pooled and could not freely flow

• Poverty reduced people’s ability to evacuate

• 2010 floods surpassed any preventative measures which meant these measures were weakened already before floods in 2011

• Deforestation and illegal logging

• Affected 33 million people

• More than 1,700 died

• 28,000 schools and health clinics damaged

• Economic loss of $30bn

• 4 million hectares of agricultural land damaged

• 800,000 cattle and livestock died

• 40% of children in affected areas had stunted growth

• 25% of children in affected areas were underweight

• Malaria, dengue fever, diarrhoea

• More than 20 million people affected

• 1.2 million homes damaged

• 1,600 deaths

• 11,000 schools closed

• Losses of $1bn+ in the agricultural sector

• 3.6 million hectares of agricultural land destroyed

• Rain in June and July was 20% higher than ever seen before

• On 25th June, the month’s rainfall fell in 1 day

• Jet stream did not move as normal (La Nina) so bad weather stayed over Britain

December 2015 was the wettest month and second wettest winter since 1910 in the UK

Record maximum peak flows in North England

• Estimated £3bn of flood damage covered by insurance and £3bn not covered by insurance

• 500,000 homes affected nationwide

• In Hull, 10,000 homes were damaged

• 340,000 people left without running water for a week in Gloucestershire

• Cost of repairing roads in Gloucestershire was £25 million

• 5,200 homes across Cumbria and Lancashire flooded

• 43,000 homes in North-East England had no power

• 2 people killed

• £500m damage across Cumbria

• 1,000 evacuated in Cumbria

• 40 schools in Cumbria closed

Ice melt - 40%

Thermal expansion - 60%

• China - heatwave led to flash floods and low levels in the Yangtze

• Australia - high rainfall caused flood events

• Brazil - Intense rainfall, causing flash floods and landslides

• Europe - hot summer led to flash droughts and low river levels

7% per degree C of warming

2022 was the third La Nina in a row

90%

46%

1700s and 1800s

85%

733 million+

25% e.g. Nile

22% industrial

6% household

2% drinking water

70% agricultural

Mexico - pesticides and fertilisers

Arizona - irrigation increases salinity

Bangladesh - aquifers overdrawn

Mexico City - ground subsidence

Pakistan - excessive pumping, wells drying out

NE China - industrial pollution

California - saltwater incursion

3 million

• Leading to a falling water table

Developing high tech products e.g. laptops

50L costs 0.1% of typical daily salary in the UK

50L costs 108% of typical daily salary in Cambodia

50L costs 45% of typical daily salary in India

104%

80%

1.3 million

300 million

75% major lakes

25% coastal zones

Liver + digestive cancers cause up to 80% of deaths - water pollution

137 million in 70 countries

20%

1000m³ per year

This can be met by 60% of global accessible freshwater supplies

50%

60%

66%

4 billion

181 gallons

More water than any other US state - US average is 80-100 gallons

60.7% irrigation

16.6% public supply

1.0% industrial

250km wide

Under 100mm rainfall due to the rain shadow of the Sierra Nevada mountains

3.5% - seasonal shortages

2 million in 1900s to 39.54 million in 2020

75% of demand from south of Sacramento but 75% of rainfall in the North

Sector decreased by $1.2 billion and lost 8700 farm jobs

0.5 million acres in order to stabilise aquifers

Chinook and Coho

• Individuals and companies reduce their water use

• More efficient irrigation methods

• Irrigate less land e.g. gardens, golf courses, parks

• Recycling wasterwater

• Storm water capture

• Desalination

• Changes to water rights and usage laws

1 billion

2.5 billion

80 cents per 1000L

$5.6 per 1000L

• Lack of infrastructure

• 70s and 80s

• Due to the neo-liberal view popularised by Thatcher

• Water would be best managed by private companies as there would be a profit motive for efficiency, investment and conservation

• Structural Adjustment Programmes to help developing countries overcome debt

• Part of this included the privatisation of utilities including water

• TNCs from western powers often take over these utilities - fair?

• In 1999 water supply was privatised but in 2000 this was undone

• Prior to the privatisation, only 57% of the population was covered by gov. water

• There was 50% leakage, rationing and a lack of investment

• Dependency on private wells, vendors and carriers

• The privatisation increased water price by 35% but the service quality didn’t improve

• There were riots, protests and violence in response - 12+ people died

• 80,000 people occupied the main square

• The privatisation gave the water company a monopoly over all water infrastructure, including the informal supplies