AFRICA our HOME - WATER

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AFRICA

Our Home WATER Revised Edition


WATER

The essence of life The human body is 70% water and the same goes for most other living things. We all depend on it and can’t do anything without it. In fact the evolution, the very existence, of life on earth, depended on the presence of water. All life depends on it. Internationally, water is the most precious resource we have. We live on a blue planet, with most of the surface covered by seawater, but it is all salty and cannot be drunk. Only 2.5% of the world’s water is fresh, and of that, 99% is frozen in glaciers and polar ice or hidden deep underground, 6.5 billion people share the remainder. Many experts believe that wars will be fought over wa;er in the coming decades. Keeping the water we have clean, and using it wisely is very important.

DID YOU KNOW? In 2020 Ethiopia completed a dam that will hold back 74 billion m3 of Nile river water. Political disputes, controversy and negotiations have continued for a decade.

"ACCESS TO WATER IS A FUNDAMENTAL HUMAN NEED AND THEREFORE A BASIC HUMAN RIGHT" (Kofi Annan, Secretary-General of the UN, 1997-2006)

FUN FACTS Even different countries have to share water. In Egypt, 90% of freshwater used comes from the Nile. Yet, the Nile is shared between the 10 nations along its banks.

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WHERE DOES WATER COME FROM?

All water circulates continuously in the water cycle

Moist air blown inland and cooled by mountains to fall as rain

Rain falls and runs down plant stems into the spaces between the soil, ending up as groundwater which collects on top of, or inside rocks. Water that lands on hard soil or concrete runs over the surface into watercourses like rivers, and into ponds and lakes. Eventually, the river water runs to the sea. Water evaporates (turns into gaseous form) when it heats up, rising into the air and then the upper atmosphere. There, in the cool air, it condenses into clouds, creating water droplets again which fall down as rain. The water cycle is ‘watertight’: no water ever leaves and no new water enters.

Groundwater In some places groundwater is continuously recharged, in others it is not. In Southern Africa, 65% of rainfall evaporates quickly from the surface, 14% runs off into rivers, 20% goes into the air from plant leaves - a process known as evapotranspiration. Only 1% of rainwater ends up replenishing groundwater supplies. There is a vast groundwater aquifer under the Sahara Desert. Some is ‘fossil water’ that has been there for one million years: rainwater and runoff add 1.4 km3 every year!

FUN FACTS ‘Hydrology’ is the study of water. Hydrologists are people who specialise in studying or working with water

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Soak in


THE WATER CYCLE Condensation

Rain Transpiration

Runoff

Evaporation

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WATER USE

As a country becomes more industrialised and produces more manufactured goods, like canned and bottled drinks, processed foods, printed materials, cosmetics, and machines the demand for water increases hugely. For example, it takes 22 litres of water to produce one glass of the kind of concentrated orange juice that is often sold from a carton. This is because of the water used to grow the fruit trees, manufacture the cartons, make the concentrated juice and then rehydrate it. All such processes take huge amounts of water.

DID YOU KNOW? •

One flush of a water closet toilet can use as much water as some people use in a day for drinking, cooking, and washing.

People who have water piped to their houses use more than three times as much as households without. People who fetch and carry water are much more careful how they use it.

Leisure activities such as golf and swimming consume huge amounts of water.

Agriculture uses 69% of global water use, industry uses 19% and homes use 12%.

The World Health Organisation estimated 50 litres of water per person, a day are needed to ensure public health and basic needs are met.

In 2018 Cape Town in South Africa was days away from being the first major world city to run out of water.

ACTION SHEETS - 26: Building toilets, 19: Spring protection, 14: Rainwater harvesting, 12: Developing a plan for community water security

Watch the films on Ecosan Toilets and Harvesting water at home 42 | Water


What could people living this side of the picture do to make their water use more sustainable?

What could those living on this side do to improve their management of available water?

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WATER SHORTAGE

Despite being 20% of the world’s land area, Africa has only 9% of the global freshwater resources. In dry areas, people queue for hours to access their daily water requirements. More than half of Africa receives less than 500mm of rainfall per year, yet Africa also has the third wettest place on the planet.

Why does it rain where it rains? Rain can only fall from air that is carrying water. In areas with an equatorial climate, like parts of Cameroon, The Democratic Republic of Congo and Gabon, it is humid and rains a lot. The rain comes from currents of air that have traveled over the sea, picking up moisture that forms clouds. An equatorial climate typically receives rain all year round but the inter-tropical convergence zone (ITCZ) intervenes. The ITCZ is where these moist winds meet dry, hot winds moving south from the Sahara. The convergence causes violent storms and heavy rain. The ITCZ moves north and south across the equator seasonally, according to where the sun is hottest. This movement causes dry and wet seasons. Each year as the ITCZ moves south, countries like Zambia, Tanzania and Ghana have a rainy season. For the rest of the year, countries in this zone are mainly dry, because the air they receive has been traveling overland and has already lost most of its water. In the semi-arid drylands, found in countries such as Botswana, Sudan, Senegal and Ethiopia, the rainy season is shorter with even less rainfall. In the driest parts of Africa, arid zones like the Sahara Desert, it hardly rains at all. The highlands of Kenya and Ethiopia receive lots of rain, because clouds form as the air rises over the mountains.

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What about droughts? The global climate is a huge interlinked system. Small changes in temperature and air pressure in one area cause changes to air currents and rainfall elsewhere. Where there is less than 500mm of rain in a year, crops cannot grow without irrigation. In semi-arid areas, even a small reduction in rainfall can lead to failed harvests. People can plan for variable rainfall, and prepare reserves of food, but when there is a drought – when rainfall is lower than average for more than one year – food reserves may run out. Many countries suffered severe droughts from 1968-73 and from 1980-82. Between 1999-2012 Eastern Africa had 6 years with poor rains; 2011 was the driest year since 1951. Millions of people in Sudan, Eritrea, Ethiopia, Somalia and Kenya are suffering as a result. Drought is also linked to famine in Western African countries like Niger, Mali and Burkina Faso, and food shortages in Southern African countries such as Zambia, Malawi, Zimbabwe and Mozambique. Droughts may happen more often because of climate change caused by human activity. This is explained in the Energy and Climate Change booklet.

ACTION SHEET - 10: Health problems from a lack of Water

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GETTING WATER TO YOUR HOME - THE SOLUTIONS

It is often the job of women and children to fetch water for domestic use. In the countryside, women often walk ten miles or more every day to fetch water. In the dry season women may have to walk twice as far. Constantly carrying heavy weights on the head, back or hip can damage women’s bodies. Back-ache and joint pains are common. In extreme cases, women’s spines curve and the shapes of their pelvises change, making it hard for them to give birth. Girls are sometimes kept out of school because they are needed to carry the family’s water. This is very bad for their education. Some solutions to this problem include: •

Pumping water to a tap-stand in the village using mechanical or electrical pump

Solar powered pumps are perfect

Digging a well or borehole close to the village

Collecting and storing rainwater

Installing a gravity water system

This is a roundabout pump. As the children play, water is pumped from under the ground (www.playpumps.org)

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It is always vital to involve as many people as possible in decisions about water supplies. The whole community needs to work together to put the system in and keep it working. You can form a committee to make decisions on the type of water supply system and how it will be managed and paid for. If care is not taken a new water supply can have unexpected effects. Nomadic pastoralists traditionally move with their livestock, following the rains. Having a fixed water supply may lead them to settle in one place, changing generations of custom, skill and habit, and creating environmental problems if care is not taken. Pumping water: Groundwater has been filtered by the soil and is often cleaner than surface water. Accessing it can be difficult. All sorts of clever devices have been invented. Some are easy to build, such as the rope and washer pump, made from old bits of bicycle. Others are more complicated and require help from engineers. How the system is powered depends on how far the water lies beneath the surface. If it’s not too deep, a treadle pump, which runs on peddle power, can work well. Hand or foot pumping is hard work if groundwater is deep, so some pumps have motors. The way they are powered is critical. Running out of diesel can mean no water. Solar is an option and if there is enough wind you could use a wind pump. Chapter 5 tells you all about this. ACTION SHEETS 12: Community Water Security, 16: Getting Groundwater, 18: Useful Water Pumps

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KHOTSO - PULA - NALA PEACE - RAIN - PROSPERITY A Basotho proverb

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Rainwater Harvesting One simple way to improve water supplies is to harvest the rain. Your roof can provide your water. A gutter collects the rain from the whole of your roof surface. Be careful it is not made of poisonous material - steel is best. Keep the water container covered so that malaria-carrying mosquitoes cannot breed in it. This prevents animals and children falling in too. The picture shows a rainwater-harvesting house in Kenya. More rainwater can be collected in speciallybuilt ponds or pits, in tanks, or even buckets. Building small underground dams can stop rainwater draining away into the earth and save it for later use. See Chapter 3 for ways in which farmers are harvesting rainwater for their crops.

Using water wisely Another way to help the problem of water shortage is to use the water you have more wisely. Much water is wasted in agriculture. When water is simply flooded into a field through ditches and channels, most of it ends up evaporating. Too much irrigation can also cause salinisation, making the soil too salty for plants to grow. This lady from Zimbabwe is using a drip irrigation kit to feed small amounts of collected rainwater directly to her plant roots, using the minimum necessary. Reuse your water! Re-used water can be used in the garden or farm to grow your crops. It is not enough that water is accessible, it also needs to be clean. The next section explains why this is so important. ACTION SHEETS - 13: Roofwater Harvesting, 15: Rock Catchment Rainwater Harvesting, 18: Drip Irrigation

Watch the film on Harvesting water on the farm 49


DIRTY WATER INDUSTRIAL POLLUTION

There is a saying in engineering: the solution to pollution is dilution. The idea is that things can be put into the water and just disappear, causing no problems. Waterways and oceans are therefore used as big dumping grounds for chemicals produced by factories and sewage farms, waste oil and heat. Recently it is becoming accepted by ecologists and individuals, community groups, governments and by industry that water cannot cope with the poisons we place in it – that dilution is not the solution.

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Industrial processes use water (about 20% of all water used by humans) and often return it to the waterway full of chemicals. Products which you may not think of as needing water are often the worst culprits. Paper, iron and steel, the chemical industry, and plastic manufacture are among the worst.

Water used by industry Steel Paper Bread

155m³/tonne 300m³/tonne 2-5m³/tonne

In 2014 75% of industrial water use was for energy production. UNESCO 2014. We need to improve on this. Some of the chemical by-products of industrial processes, including heavy metals, like lead and mercury, are known to be damaging to life. Other chemicals have only recently been developed by human technology, and we have no idea of their effects on us. Indeed, the effects are often hotly debated by scientists and ecologists. Chemicals dumped into rivers end up in people’s fields, crops and drinking water, and in the bodies of animals living in the river. Some create cancers and others kill. Some are genuinely harmless. A chemical is a pollutant when it has bad effects in the environment. For example, fertilisers added to the soil and running off into rivers can cause algae (river plants) to bloom. This is called eutrophication. When the algae die and rot, they take all the oxygen out of the water, so nothing can grow. Heat is another form of pollution from industries that require large quantities of water for cooling. Water may be returned to the river too hot to support life. Because rivers flow, sometimes the people most affected by pollution are not those causing it. One way or another, we all live downstream. Industrial processes are being developed to reduce pollution and use less water. Waste water is even treated, reused and recycled - a way to make money, protect people and the environment.

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DIRTY WATER THE RISK OF DISEASE

Diseases live in dirty water. Six thousand children die every day from diarrhoea, due to lack of safe water. It kills more children than anything else. Some people do not understand or accept that there is a link between drinking water and disease.

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How diseases are spread through water Some diseases get into the water from human faeces. Some diseases live inside water animals such as snails and then transfer to humans through skin contact. Some disease could be prevented if we are able to wash using more water and soap. Common diseases related to dirty water and unsafe hygiene practices are: cholera, hepatitis A, dysentery, giardiasis, polio, diarrhoea, typhoid, salmonella food poisoning, bilharzia (schistosomiasis), guinea worm, hookworm, tapeworm and trachoma. If your water comes from a river or source that is contaminated, it can be made safe to drink in many simple ways. Learn how on the next pages.

GOOD DRAINS Mosquitoes that carry malaria breed in standing water, so cover water containers and build drains to carry water away from your house and school.

ACTION SHEETS - 11: Health problems from unsafe water, 27: Wash Your Hands, 28: Making Soap

Watch the film on Making water safe to drink

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MAKING WATER SAFE

Simple water treatment techniques for use at home can change lives, easily and quickly. Boiling - making sure that water is bubbling at 100°C - can kill disease organisms. However, water does not necessarily need to boil to be safe to drink. You can use a solar cooker to heat water up and keep it at a temperature of at least 65°C, long enough to kill pathogens. This is called solar pasteurisation. Putting water into a clear plastic bottle and leaving it in the sun for at least 6 hours can also make it safe. How fantastic that shining up there in the sky may be the solution to your dirty water problems, free and easy to use. Chlorine tablets and water filters can also be very useful. At Rugusu Springs in Kenya, people used to water their cattle, wash their clothes, bath and collect drinking water in the same place. People were getting ill, both in Rugusu village and further downstream. They solved the problem by fencing off the spring, and piping the water into three concrete channels. One leads to a watering place for cattle, one to a washing and bathing area for village use. The third goes back into the stream. Now, the community is healthier, and so are people living down-river. Local councils or government can make sure that clean water comes through taps. Ultraviolet light can be used to disinfect the water for a whole community. This avoids the use of too many chemicals in the water.

ACTION SHEETS - 23: Making Water Safe, 24: Water Filters, 25: Solar Pasteurisation, 26: Building Toilets

Watch the films on Eco-san Toilets and A Community Spring

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Use a toilet (but not a water closet) 192 million people have schistosomiasis in Africa. If people did not use canals and streams as toilets, this disease would probably not exist in many places. Stop faeces and urine from getting in the water source. Do not allow people or animals to defecate or urinate near the river or well. Using water in a toilet is very unwise anywhere in the world because it is a rare and precious thing. There are many clever ways of disposing of human excrement. If it is allowed to rot in dry conditions, the temperature will increase to a level where the harmful pathogens (germs) are killed off. This is what happens in an eco-san toilet. Eventually, the human faeces can be used as a harmless and rich manure. It is a smelly but worthwhile process. In an eco-san toilet, urine is kept in a separate chamber. Urine contains nitrogen, which is a crucial element for plant growth. In rivers it can cause destructive eutrophication, overgrowth of algae, which blocks the light on the river bed and kills off plants and animals. On your crops, however, it can work miracles. Maize can grow to more than twice the size! Urinating in the right place – in an eco-san toilet and not in the river – is a win-win situation.

Maize Experiment In an experiment conducted by Aquamor in Zimbabwe, maize plants were grown in 10 litre cement containers and fed with varying amounts of urine.

THE RESULTS Water only

3:1 mix of water and urine 0.5 litres, 3 x a week

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WATER IS ESSENTIAL TO ALL LIFE, NOT JUST HUMANS

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DAMS

A dam is a man made structure which blocks a river causing a reservoir of water to form behind it. Dams can be small, for a stream on your farm, huge like Kariba in Zimbabwe, or anything in-between. Dams can be used to make electricity. Turbines are placed inside and as water passes through holes in the dam, it turns the turbines to generate electricity. More than 45,000 large dams have been built around the world to generate electricity, to supply water to crops and people, control floods and help ships and boats move around. Big dams are very expensive to build. They can be extremely useful, but can also have horrific side effects and some people now believe that the costs outweigh the benefits. When a large dam is built much of the land upstream is lost under water. Rivers and riversides can be the most fertile places for agriculture. The river carries rich sediments from dissolved rocks and fallen leaves and other organic matter. These are deposited on floodplains along its journey. As all of life depends on water, rivers are also very rich in wildlife. Fish which travel between the sea and the river to complete their life cycles are unable to do so when a large dam is built. They may even go extinct. One third of the world’s freshwater fish are threatened with extinction. People who used to live alongside the river are also affected. Their entire community may be flooded out, and their way of life and livelihood lost. The Kainji Dam in Nigeria, for example, displaced 50,000 people. The loss of annual floodwater downstream reduces crop yields and water availability for many thousands more. During the 20th century an estimated US$20 trillion has been spent on dams. Among many other projects, a big new dam was built on the Komati River in Swaziland in 2001, the Mphanda Nkuwa Dam in Mozambique was commissioned in 2015 and the Grand Inga Dam in DRC in 2016. However, the Renaissance dam in Guba Ethiopia will bring electricity to millions of poor, in Ethiopia and beyond.

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WATER

ACTIVITIES

ACTIVITY 1 How much does it rain where you live? Make a rain gauge and record the amount of rain every day. You need: • A tin with straight vertical sides • A wooden ruler • A saw Cut the ruler with the saw so that the ‘0’ mark on the ruler is exactly at the end. Place the tin in an open space away from trees and buildings, but somewhere safe where it will not be disturbed by animals. Check the rain gauge every day at the same time of day by placing the ruler vertically in the water in the can and measuring the water level against the ruler. Once the measurement has been taken, empty the water away and place the tin upright again in the same place. Keep records of the rainfall each day. Record 0 for days with no rainfall. To relate this measurement to rainfall on the land, every 1mm of rainfall in your rain gauge is equivalent to 1 litre of rain falling on 1 square metre of land. Based on an activity from the VSO Agricultural Science Teacher’s Handbook by Peter Taylor

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ACTIVITY 2 Rainwater Harvesting Investigation Is rainwater harvesting is happening in your area? What types of tanks and gutter systems do people use? If nobody is harvesting the rain, why not? • Find out about rainfall where you live. Local agricultural organisations might be able to help, or you could use the results from your rain-gauge. Make a graph to show rainfall (in mm) in different months. • Use a measuring bottle to measure the amount of water you use at home or at school for a few days. Find out if your school knows how much water it uses per day. If not, find out if you can measure it! • Measure the roof of your home or school and calculate how much rainwater you could collect in each month. Would this be enough water for use everyday? Rainfall (mm per month) x area of roof (m2) x 0.5* = litres per month. *Up to half the water will be lost before it reaches the tank because of evaporation.

More information on roofwater harvesting can be found in Action Sheet 13

ACTIVITY 3 Fish Life Make up and write down or act out the story of a fish born at the top of a clean river. As he swims down the river, the water becomes polluted with as many different substances as you can imagine. Think about what people are doing beside the river to cause the pollution. Perhaps your fish could swim back up river and tell people what they could do differently to help keep the river clean!

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ACTIVITY 4 Rugusu Roleplay This is a group activity about improvements to the water supply at Rugusu Springs (see page 54 and Water film). Split your group into three smaller groups as follows: 1) Members of the water committee at Rugusu Springs 2) People from Rugusu village 3) People from another village down the river Before the channels are built, a meeting is called to discuss the project. People from the other village have heard about the plans to build channels, and they are concerned about the effects on their water supply. People from the village want to hear about new rules for keeping the river clean. How will the water committee convince everyone about the benefits of making changes at the spring? Each group should prepare questions and answers before the roleplay meeting is held.

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ACTIVITY 5 Water Quiz What do the these words mean? Make a sentence using each of the words.

Dam

Water Cycle

Water Borne

Drought

Ground Water

Ocean River

Eutrophication

ITCZ

Contamination

Water Management

Irrigation

Hydrology

Flood

Downstream

Sediment

Potable water

Pollution Rain

Clouds Seasons

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