GCSE Geography Unit 1: Physical Geography

Water on the Land

CASE STUDY

REVISION BOOKLET

Please note: This booklet contains case study revision only!

You should still use your topic cover sheet to see what other knowledge you are expected to have

A case study of flooding in a rich part of the world and one from a poorer area-the different effects of and responses to flooding.

England (MEDC) Bangladesh (LEDC)Date & Time

July 2007 Summer 2004

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Changes in the JET STREAMThe unusual position of the Atlantic jet stream has been blamed by some. "This year it has been much FURTHER SOUTH for much of the summer resulting in areas of LOW PRESSURE (a depression) right across the UK which causes HEAVY RAIN,"Convergence of Air

Masses

On Friday July 21st, a cool weather system spinning over the Atlantic drifted into Britain and collided with warm air that was bringing heat waves to Spain, France and eastern Europe. The warm air rose, cooled, contracted and released its moisture in a 24-hour of non-stop rain.

Heavy RainfallAs a result, during May June and J uly therainfall in the Severn Valley was higher thanusual 400mm fell across the UK . It was the

wettest period since records began in 1776 water soaked into the ground it became saturated.

Almost two months of rain fell in one day on Friday 21st July 2007.

RELIEF The flat and low-lying nature of the landscape surrounding the river Severn.When water breached the banks of the River Severn’s channel it just spread across the land for long distances

THREE MAJOR RIVERSThe Meghna, Brahmaputra and Ganges rivers flow through Bangladesh from India and the Himalayas to their mouth at the Bay of

Bengal, bringing water into Bangladesh from a catchment 12 times the size of Bangladesh itself.

Heavy Rainfall and a MONSOON CLIMATE, heavy rains between May- September every year, when moist winds blow from the sea.The continuous rainfall fell on saturated soil increasing surface runoff into rivers

Melting snowFrom glaciers in the Himalayan mountains during late spring and summer increased

discharge in the Brahmaputa and Ganges river.Peak discharge occurred in both rivers at the same time which increased discharge down stream

TROPICAL CYCLONES cause storm surges where sea water is funnelled up the Bay of Bengal and onto low lying coastal areas causing coastal flooding. Coastal flooding also hinders the drainage of the 3 major rivers, into the sea causing the water to back up making them more prone to flooding.

Relief LOW, FLAT COUNTRY. 80% of Bangladesh is located on floodplains and river deltas, 70% is less than 1 metre above sea level, so once the rivers overflow the water can spread vast distances.

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an URBANISATION on the floodplain

The FLOODPLAIN of the River Severn is built on therefore when the river floods it floods into towns and cities, such as Tewkesbury, Upton,

Worcester & GloucesterBy concreting over the land impermeable surfaces have increased surface runoff (rain reaches the river more quickly through man-made drains etc.)

Settlements built at confluences

Many major settlements are located at the confluence of two major rivers creating a bottle neck and so flood risk is greater here as the high discharges from both come together in one location.

DEFORESTATIONTrees cut down in upperparts of River Severn Drainage Basin. With the building of urban towns & cities on the floodplain, the amount of vegetation in the area surrounding the river was reduced. It reduces the amount of interception, which in turn increases the amount and speed of surface runoff into the river.

LACK OF PREPARATIONDespite warnings, towns were unprepared and so the floods were worse than they could have been E.g. Flood defences destined for Upton upon Severn in Worcestershire had not reached the town in time because the vehicle carrying them had got stuck in the flood chaos on the M5 motorway.Blocked drainage channels. Rubbish and debris carried by the rivers. Ditches not cleared.

Global Climate ChangeWeather experts referred to it as “freak Weather” rather than as a result of climate changeSome scientists link the change in weather systems over the Atlantic to Global Climate change.

URBANISATION on the floodplain

GROWING TOWNS and CITIES, eg Dhaka, are expanding rapidly without proper drainage planning. Increased impermeable surfaces (concrete and tarmac) rainwater cannot infiltrate into the soil. Instead it either sits on the surface, causing URBAN FLOODING, or becomes surface runoff, reaching the river more rapidly, reducing the lag time, and increasing the risk of RIVER FLOODING.

POPULATION GROWTH is high, making it the most densely populated country in the world. 1961 = 55 million people, 2010 = over 155 million. As a result people have been forced to cultivate MARGINAL LAND, which is more prone to flooding.

DEFORESTATION. Due to increased demand for fuel, farm land and building material. Reducing interception and root uptake occurs so more water reaches the river more quickly, increasing the flood risk (shorter lagtime, higher peak discharge). In Nepal, 50% of the forest cover that existed in the 1950s has been cut down.

SOIL EROSION as a result of deforestation as soil is washed from the slopes by surface runoff. This causes SILTING of the river. Silt deposited on the river bed raises the river bed (Brahmaputra rising 5cm/year) and reduces the river channels capacity, increasing flood risk in Bangladesh.

LACK OF PREPARATIONEven though emergency warnings were transmitted by radio most people cant afford radios,

Global Climate ChangeGLACIER RETREAt (melting)in the Himalayas as a result of GLOBAL WARMING. In some places glaciers have retreated by 300m in 30 years Results in rising sea levels, which in turn makes it more difficult for rivers to drain out of Bangladesh into the sea as they collide with the rising sea waters causing a backlog.

Comparing Flooding Case Studies: IMPACTS/EFFECTS

UK, July 2007 (MEDC) Bangladesh, May – Sept 2004 (LEDC) Comparison/ Discussion PointsSO

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PRIMARY SOCIAL EFFECTS

13 deaths – mainly people were swept away by fast flowing water

56,000 homes were flooded

1000s of people were stuck on the M5 motorway

350,000 people in Gloucestershire (150,000 people supplied by the Mythe Water Plant) were left without tap water after the water treatment works was flooded.

½ million people were temporarily left without electricity as powers stations were flooded.

SECONDARY SOCIAL EFFECTS

Sewage from drains mixed with flood waters, creating a health hazard.

5500 families had not been able to return to their homes a year later, of which 1400 were still living in caravans.

A sense of Community developed amongst the people of Tewkesbury, which has continued to some extent

1 in 4 residents from the worst affected areas reported to have suffered significant mental health problems (e.g. depression requiring medication).

1 in 3 residents in worst hit areas reported to have experienced a negative impact on their family life and relationships due to the stress of the situation (e.g. poor child behaviour at school, young afraid of heavy rain)

PRIMARY SOCIAL EFFECTS

Over 750 deaths were reported

Some 8.5 million people were left homeless (although some sources say it was as many as 30 million people)

In many badly hit rural areas, rice - the main food crop - was washed away and other important food supplies such as vegetables were lost along with cash crops such as jute and sugar.

SECONDARY SOCIAL EFFECTS

100,000 people in Dhaka alone (the capital city) were suffering from diarrhoea as the flood waters left mud and raw sewage in their wake.

More than 1 million children suffered from malnutrition and disease in the months following the floods.

The large scale of the flood in Bangladesh was difficult enough but the relief effort was hampered by the inaccessibility of many areas.

Loss of crops could result in increased crop prices in both nations but starvation/ malnutrition is a real danger in Bangladesh as many are reliant on aid from abroad which takes time to arrive and is not easily distributed due to damaged transport networks.

Bottled water was provided almost instantly in England but, again, people in Bangladesh were largely reliant on overseas aid…time consuming and difficulties in distribution.

Diarrhoea medicine would be widely available in England but in Bangladesh diarrhoea can be life threatening if people are forced to drink dirty water and the condition goes untreated.

UK, July 2007 (MEDC) Bangladesh, May – Sept 2004 (LEDC) Comparison/ Discussion Points

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Damage was estimated to have cost £3billion across the whole of the UK.

Tewkesbury was completely cut off with no road access from any direction and rail networks flooded causing major travel disruption to people/ businesses from a much wider area, resulting in a fall in economic activity.

50km2 of Agricultural land was flooded. Crops, ready to harvest, were ruined, especially broccoli, peas, carrots and potatoes. 40 % of the pea crop was lost.

7000 businesses were flooded

Most businesses were unable to re-open straight away when the flood waters fell, meaning businesses lost profits in the long term (e.g The Tea Rooms in Tewkesbury didn’t re-open for 8 months after the floods as it had to be fully refurbished)

130,000 insurance claims were made. As a result insurance premiums increased by 3 to 4 times for the residents of Tewkesbury and in some cases residents could not actually get insurance cover for the future as they were too big a risk for the insurance companies.

Some residents in Tewkesbury have found it difficult to sell their homes due to their history of flooding. As a result they are forced to stay in the area or sell their homes for much less than they bought them for.

Damage was estimated to have cost $7 billion. Rebuilding of Roads and industry was estimated to have cost the government $2-3 billion

Over half of the country was under water, including 40% of the capital city Dhaka and Dhaka airport.

Every $ spent on repairing damage is another $ not being spent on improving other facilities/services in the country

Most farmers in England are commercial farmers so loss of crops is unlikely to be life threatening, whilst many farmers in Bangladesh rely on their crops to feed their families (subsistence farmers)

The majority of Bangladeshi residents/ farmers are unlikely to have insurance so if everything is lost in the floods, they have to start again with nothing!

Comparing Flooding Case Studies – RESPONSES

UK, July 2007 (MEDC) Bangladesh, May – Sept 2004 (LEDC) Comparison/ Discussion PointsIM

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Residents placed sand bags in their doorways to try and prevent flood water from entering their homes.

The Gloucestershire Fire and Rescue service attended 1,800 calls in an 18 hour period, sending out search and rescue boats to help people get from their homes to safety.

The RAF airlifted people from homes, cars and boats.

An Amphicar was used to ferry food to over 100 school children who were stranded by floodwater at Tewkesbury High School.

5 million litres of bottled water were distributed to customers of Severn Trent Water and over a 1000 Water Bowsers and 90 tankers of water were set up by the company across the flooded area, costing the company £25 million over the 8 weeks it took to restore the normal water supply.

The United Nations (UN) launched an international aid appeal for $74 million but had received only 20% by September.

Food supplies, medicines, clothing and blankets were distributed although this was difficult due to the effects of floods on transport networks. Emergency food aid was needed until the following year’s harvest.

An appeal by WaterAid sought to supply water purification tablets and posters highlighting the hygiene risks in flood water.

Bangladesh had to rely heavily aid/ relief efforts from overseas, whilst the UK’s own emergency services were able to cope with the scale of the disaster.

UK, July 2007 (MEDC) Bangladesh, May – Sept 2004 (LEDC) Comparison/ Discussion Points

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SHARD ENGINEERINGIn Upton on Severn, a permanent flood wall has been constructed in 2011, after their temporary barriers got stuck on the M5 in the 2007 floods. There are not enough properties at risk in Tewkesbury to make such a response cost effective.

A flood wall and an earth embankment have been built around the Mythe Water Plant costing Severn Trent Water less to build than the cost of the previous flood.

The environment agency has:- Completed 34,000 new flood defences, protecting 30,000

homes

SOFT ENGINEERING STRATEGIESThe environment agency has:

- Signed up 73,000 more people to its free flood warning scheme and has improved flood warnings so they are specific to certain areas of the community and therefore people will take them more seriously in future

- employs people to monitor the waterways & clear debris that builds in order to improve the flow of water and prevent any bottlenecks which could result in future flooding

Residents have been encouraged to buy their own flood gates costing £2000 which will hopefully be more effective than sand bags in future floods.

Residents have purchased new, lighter furniture, which can be carried upstairs easily in the event of future floods so that it won’t be damaged.

New housing developments which are being built on the floodplain, now have to consider how flood risk could be reduced. Instead of impermeable concrete pavements, permeable pavements (e.g. gravel) are created and water is channelled towards community pond areas (soft engineering), instead of into storm drains.

HARD ENGINEERINGEmbankments have been built along stretches of the river, raising the river banks to protect areas where it is deemed to be cost effective (e.g Western Dhaka)

Cluster Villages have been created, which are raised areas of land upon which approximately 100 households and shared community facilities (such as wells/ schools etc) are built

SOFT ENGINEERING STRATEGIESFlood warning systems have been improved and more flood shelters have been built by Non-governmental organisations (NGOs) such as Red Cross and Oxfam, providing temporary emergency shelter during future floods.

Diversification of Livelihoods: Non-Governmental organisations have helped farmers to look at alternative ways to earn a living, which won’t be affected so much by flooding, including

fish farming Pumpkins (sand bar cropping) – locals have

been trained to grow pumpkins, at 75% profit, on land previously thought to be too sandy. Pumpkins grow well in sandy soils, grow during the dry season and can be stored to be sold at flood times when the demand is high

Superducks – duck farming: a small flock of ducks can be bought on credit but then the owners are able to sell between 200-400 eggs a day. The ducks also feed off the insects on the farmers crops so act as a natural insecticide, whilst the duck droppings act as a natural fertilizer.

The ability to continue making a living during times of flood, will help to improve families standards of living in the rural areas which are unlikely to be protected by hard engineering (as they are not seemed to be worth protecting on when looking at the cost-benefit analysis!). Profits have helped farmers send their children to school and buy more cattle/ chickens with the profits, helping them climb out of the cycle of poverty.

A case study of a dam/reservoir and to consider the resulting economic ,social and environmental issues and the need for a sustainable supply.

Water Transfer Case Study:Kielder Water

Introductory factsKielder Water is the largest artificial lake (reservoir) in the UK at 10km long (hard engineering scheme)Planned in the 1960s Opened in 1982 Many parts of England have more water than they need – so water stored in reservoirs like Kielder water is used to supply cities and industries like Newcastle and Tyneside where the demand for water from the then growing chemical and Steel Industries on Teeside exceeded the supply of water. The water is then transported long distances aqueducts, pipelines and existing rivers to where it is required

Cost £167 million pounds LocationLocated in the North-East of England (in the county of Northumberland, close to the Scottish Border. North-west of major settlements of Newcastle and Sunderland

Why was this particular site suitable for the construction of a dam and reservoir?Physical

The River North Tyne valley had a large, relatively wide floor, with steep sides and so created a natural basin to be dammed.

Impermeable rocks so water doesn’t seep through Annual precipitation was high (1370mm) so water supply was plentiful

Human Few people lived in the valley so only a few families needed to be removed and re-housed The land was mainly poor quality farmland, remote (far away) from farmers markets in the lower Tyne valley.

How the scheme works by transferring water from an area of surplus to areas of deficit – where needs cannot be met.

Water is transferred to the populated parts of the north-east Newcastle and Tyneside Water is released from the reservoir directly into the River North Tyne

From the River Tyne it is pumped through a tunnel under the highland between the valleys. The tunnel feeds into other East flowing rivers, especially the River Tees. To provide water for Middlesbrough and Teeside

Water from Kielder is also used to supplement the River Derwent flow when the Derwent reservoir is low

Pipeline extension – Drought in Yorkshire in 1995 led to a 13km pipeline link being built from the Lower Tees to the

Ouse River system for use in York

How successful has the scheme been?The north-east enjoys the most reliable and sustainable water supply in EnglandRestrictions on water use, such as hosepipe bans, are unknown in the area, even in the driest of summers such as 1995, when even the Lake District reservoirs dried up. Economic, Social and Environmental Impacts?

Social Economic Environmental

Schools and youth groups use the area for recreation ¼ million visitors each year

The conservation hatchery for Salmon breeds the Arctic Char, unique to Ennerdale Water but in decline in the wild.

The Calvert trust provides activities for the disabled along with an orienteering course and water sports

Caravan sites, youth hostels and hotels accommodate people and provide jobs and income (multiplier effects)

Water levels always remain high – drought has never been known

Skyspace is a hilltop observatory and a sculpture trail links this to the centre

A visitor centre and local shops all benefit from tourism

Northumberland Water manage the area to maintain good quality water

Mountain biking, downhill trials and horse riding paths have been provided

An all-terrain path skirts 40 km around the edge of the reservoir

An eco-village nearby is powered by waste chips from the forestry process

Birdwatching at the Bird of Prey centre along with Salmon fishing opened in August 2008

Jobs were made available during the construction phase and through maintenance of the dam wall

Habitats have been protected especially for the Ospreys and indigenous Red Squirrels

The HEP plant generates 6MW enough for 4000 homes per year

The Forestry commission ensure the woodland is extracted sustainably whilst protecting environments

Forestry generates cash around the reservoir