Pakistan Studies Class 9 Unit 6: Water Resources Notes

Surface Water

Life on earth depends on water, and Pakistan has both surface and ground water resources, which are needed for home, industry and farming. The Indus River is the largest and most important river of Pakistan. Its tributaries, the Jhelum, Chenab, Ravi and Sutlej, add a great deal of water. The Jhelum River runs through Punjab and Azad Kashmir and plays an important part in irrigation and the making of electricity. The Chenab River runs through Punjab and supports both power and irrigation. Tarbela Dam on the Indus is one of the largest earth-filled dams in the world and is used for flood control, electricity and irrigation. Mangla Dam on the Jhelum is another important reservoir for storing water and making electricity.

Groundwater

Pakistan depends greatly on groundwater, particularly in places that have little surface water. Water is taken out with tube wells and hand pumps for home, business and farm use. The Indus Basin Aquifer is the greatest source of groundwater. It covers the whole Indus Plain and meets most of the water needs of farming. The Balochistan Plateau Aquifer is an important supply in Balochistan, and it supports farming and the livelihood of local people. In Punjab, groundwater is a major source of irrigation, but in some places too much water is taken out, so the water table falls and salt increases.

Seasonal Changes in Flow

The dry to semi-arid climate, the monsoon rains and the melting of glaciers in the Himalayas and Karakoram affect the flow of water. In the monsoon (July to September) there is heavy rain, and the flow of the Indus and its tributaries rises a great deal, which fills the reservoirs. In winter and spring (October to April) there is little rain, but melting snow keeps the flow of the rivers fairly steady. In summer (May to June) when the winter snow has finished, the flow goes down and temperatures go up, so there is a water shortage in many places, especially in the south, and the need for irrigation rises.

Quality of Water

In the monsoon, heavy rain washes dirt from towns and farms into rivers, and floods can pollute water sources, so quality gets worse. In the dry season (October to June) there is less pollution from rain, so quality is generally better, but with less flow the pollution in some places becomes more concentrated. Water from melting glaciers is usually of high quality and is free of cost. Pakistan faces problems such as water shortage, over-use of groundwater, polluted water and poor water management.

Advantages

Irrigation means giving water to land artificially to help plants grow, especially where rain is low or irregular. Pakistan's large irrigation system, mainly based on the Indus and its tributaries, has many advantages. It gives a steady supply of water, so agricultural production increases and farmers can grow crops several times in a year. It gives food security to the fast-growing population by growing wheat, rice and cotton. Agriculture employs many people and adds to the GDP, so irrigation helps the economy. It makes rural life more stable, because farmers are less affected by drought. With water, farmers can choose from more crops, including fruits and vegetables, which gives more income. The dams and reservoirs of the system make hydropower, which saves fuel. Dams like Tarbela and Mangla help to control floods. Drains deal with salinity and waterlogging. Reliable water also helps livestock, and the Indus Waters Treaty lets Pakistan manage its share of the Indus river system.

Disadvantages

There are also several drawbacks. Heavy use of groundwater has emptied the aquifers in some areas, so the water table falls and farmers have to spend more on pumping. Waterlogging, in which the water table rises to the roots of crops, and salinity, in which salt collects in the soil, lower the soil fertility and crop yield. Dams and canals can damage habitats and harm fish. The maintenance of canals, dams and pumps is very costly. Water is not shared fairly, as small farmers often get less than big landlords, and water theft is common. Pumping water uses a lot of energy. People who live where big dams are built have to leave their homes, and water disputes arise between provinces and even with India. Irrigation water is sometimes polluted by factory waste and sewage, and old methods of irrigation waste water.

Conclusion

Pakistan's irrigation system is very important for farming and food security, but to get the full benefit it needs fair distribution of water, better canals, saving of water and sustainable management.

Solutions for Water Pollution

Pakistan needs to build more waste water treatment plants, so that sewage and factory waste are cleaned before they are released into rivers and lakes. Strict laws should be made for industries to control the pollution they release, and they should be encouraged to use clean methods of production and to reuse their waste water. Public awareness campaigns should teach people not to pollute water.

Solutions for Water Shortage

Rainwater harvesting should be encouraged in homes and communities, so that rain water can be stored for use and for refilling groundwater. In villages, small dams, ponds and water tanks should be built. In coastal areas where there is a severe shortage of water, desalination plants can remove salt from sea water. The government should make strict rules on the taking out of groundwater to avoid over-use and the entry of salty water, and should encourage the refilling of aquifers. Farmers should be encouraged to grow drought-resistant and water-efficient crops, which need less water.

Solutions for Water Wastage

In farming, modern methods such as sprinkler and drip irrigation should be used, so that water is not wasted. Canals should be lined to stop leakage. Education and information campaigns should teach people the need to use water wisely and to save it.

Government and Cooperation

The government should make complete water management plans for both cities and villages, set prices that encourage careful use of water, and spend money on research into water-saving technology. A system should be set up to monitor water supply, quality and use. Public-private partnerships can help to build and manage water projects. Pakistan should also cooperate with neighbouring countries for fair use of shared rivers, and take measures against the effects of climate change by building strong structures.

Hydropower and Flood Control

Dams, barrages, canals and reservoirs play a big part in sustainable water solutions such as electricity, flood control and irrigation, but they can also affect people, the environment, industry and farming. Dams and reservoirs make hydroelectric power, which is a reliable and clean source of energy. It reduces greenhouse gases and the use of fossil fuels. But building them can disturb habitats, change the flow of rivers, harm water life, and make communities leave their homes. Dams and barrages also control the flow of water and lower the risk of floods downstream, so they protect lives, crops and property. However, poorly kept dams can make flooding worse if water is released at the wrong time or too much is held back.

Irrigation and Agriculture

Canals and reservoirs are necessary for watering crops, especially in places where rainfall is uncertain. They let farmers grow crops throughout the year, which raises food production and the income of rural people. This gives economic growth and food security. But poor irrigation methods waste water, make the soil salty and harm the environment. Taking too much water from rivers can reduce the supply downstream. Poor water management can lead to over-use of groundwater and soil damage, and fertilizers and pesticides can flow into the water and pollute it.

Environment, Industry and People

Well-planned dams and reservoirs store water and supply it in dry periods, so both nature and people have a steady supply. For industry and people, water is necessary for growth and for drinking, cleaning and enjoyment, and a steady supply improves the quality of life. But changing the natural flow of rivers can damage ecosystems, disturb the movement of fish and harm water habitats. Silt collects in reservoirs and, over time, reduces their storage capacity. Building and keeping dams and reservoirs is expensive and has social and environmental costs.

Examples and Conclusion

Tarbela Dam on the Indus and Mangla Dam on the Jhelum are the main dams of Pakistan. Barrages such as Sukkur send water into canals, especially in winter when river flow is low. In conclusion, dams, barrages, canals and reservoirs give valuable solutions for irrigation, flood control and electricity, which help growth and human wellbeing. With good management their harmful effects on the environment, farming and communities can be reduced.