WATER SUPPLY SITUATION ANALYSIS
Answers
Answer:
Explanation:
SOURCES OF WATER
General
The sources of water in Bangladesh are surface water, groundwater and rainwater. The Ganges-Brahmaputra-Meghna river system discharges huge amount of surface water through Bangladesh, a part enters into ground to form groundwater. About 93% of the stream flow passing through the country originates from outside the Bangladesh (Khan, 1993). Rainfall within country contributes to the total water available in Bangladesh, a part of which infiltrates into ground to recharge existing groundwater and the remaining rainwater flows as surface run-off. These sources of water available for the development of water supplies have their relative advantages and disadvantages in Bangladesh context. The availability of water in terms of quantity and quality, present situation and problems associated with the sources have been discussed in the following sub-sections.
2.1.2 Surface Waters
Availability
Surface water is abundant in the wet season in Bangladesh. An estimated 795,000 million cubic meter (Mm3) of surface water is discharged through the Ganges-Brahmaputra system, in the downstream of the confluence of the Ganges and the Brahmaputra. This is equivalent to 5.52 m deep water over a land area of 144,000 km2. There are other rivers discharging surface water into the Bay of Bengal. An average annual rainfall of 2.40 m within the country partly replenishes surface water sources. Each year about one-third of Bangladesh is submerged in a normal flood, and the area submerged may increase to about two-thirds during severe floods. In the dry season water scarcity persists in many areas. In this period surface water is only available in part of the 22,155 km of major rivers, 1,922 km2 major standing water bodies and about 1,475 km2 of ponds in the country. Surface water irrigation systems in the country compete for this available water in the dry season. The perennial water bodies are decreasing with the use of more and more surface water.