The sources of getting water are very few and limited, the water availability is from three sources that are:
- Surface Water
- Ground Water
- The Sources are Uncertain
This is the main source of fresh water. It includes rivers, lakes, streams, reservoirs and all other enclosures for catching and holding rain water. The surface water of Pakistan has its origin in the Himalayan Water shed which feeds the drainage of the Indus river system (IRS).
Ground water is second largest source of fresh water in the country. In Pakistan ground water resources exploited by wells, tube wells and the karez system. The water table has great seasonal and regional fluctuations. So it is higher in the rainy season and falls in the dry season. It is easier to obtain ground water in the foot hills of the mountains where the runoff is greater and the level of the water table is higher. In dessert areas ground water is difficult to obtain as the water table is extremely low and the rate of evaporation is much higher.
Ground water is extremely useful in areas like Balochistan where canal irrigation is not possible and rainfall is variable and scanty. In big cities like Karachi where there is shortage of water due to growing population, the people are making use of ground water to meet their domestic needs. The water pumped out through pipes drilled into the ground. Ground water is both sweet and saline. Sweet water can be spread over cultivated fields. But saline water has to be drained into the sea Pakistan’s water problems are more due to the scanty rainfalls.
The lower Indus Plain gets 30 to 40 inches of annual rainfall. The rainfall in Pakistan also varies from year to year. Hence if there are heavy rains the rivers are in heavy floods and if there are no rains the rivers are dry that results in the shortage of water. In general, Balochistan, Sindh and large part of Punjab and NWFP are extremely dry areas and receive less than 250mm annual rainfall.
The Sources are Uncertain
The sources of getting water are quite doubtful and uncertain. As a general rule water level in summer is higher than in the winter. From the middle of September to the middle of the March the water flow is usually very low. In March the water runs in the rivers when the ice starts melting on the mountains. Consequently, the rivers and the lakes become dry and barren during winter. The country fall a victim to the shortage of water. The crisis of water is also due to the anti-human attitude of India.