Water Resources Flashcards
What does the term ‘water resources’ refer to?
Any of the entire range of natural waters that occur on the earth and are of potential use to living beings
Name the available water resources
- Oceans
- Rivers
- Lakes
- Groundwater
- Deep sub-surface waters
- Glaciers
- Permanent snowfields
Give the distribution of water on earth
97% - Ocean water
3 percent left ->
- 3% - Polar ice caps
- 7% - Freshwater
- 7 percent left ->
- 66% - Groundwater
- 03% - Freshwater in rivers, lakes, streams
What is surface water?
Water on land is the result of precipitation or seepage from underground which forms streams, lakes, rivers, and ponds flowing on land and finally joining the sea
What is groundwater?
The water which seeps through the cracks and crevices under the surface of the land
What is an aquifer?
An undergroundwater stream that is saturated with water and transmits water readily
Where is groundwater found?
In the soil, subsoil, or bedrock. Most of it ultimately reaches the sea.
India’s water resources account for how much of the world’s resources?
4 %
What provisions does India have to account for extensive water resources?
- Vast coastline w/ indented coasts in some states
- Surface water - from rivers, lakes, ponds, tanks
- Groundwater resources
Name the states which have vast surface water resources in the forms of lagoons and lakes
- West Bengal
- Kerala
- Odisha
What is brackish water in certain states utilized for?
Fishing and irrigation of certain crops like paddy, coconut, etc
State the reasons for the decline in groundwater levels in parts of India
- Irrigation
- Industrialization
- Increase in population
State the reasons why we need to conserve water
- The overexploitation of groundwater often results in the lowering of the water table
- The loss of vegetation causes drought and reduction of rainfall and lowering of the water table
- Irrigation utilizes more than 90% of total freshwater
- The increase in population results in scarcity of water
- Our water resources are polluted & their water can hardly be used without adequate treatment
State the methods of water conservation
- Rainwater harvesting
- Adopting water-saving technologies
- Encouraging watershed development
- Water recycling
- Preventing the pollution of water
What is rainwater harvesting?
It is the process of increasing the recharge of groundwater by capturing and storing rainwater locally in sub-surface water reservoirs
What do activities included in rainwater harvesting aim at?
- Harvesting surface and groundwater
- Prevention of losses through evaporation and seepage
- All other hydrological studies and engineering interventions, aimed at conservation and efficient utilization of limited water endowment of an area such as a watershed
Give the main objectives of rainwater harvesting
- Meeting the ever-increasing demand for water
- Reducing the run-off which chokes drains
- Avoiding the flooding of roads
- Augmenting groundwater storage & raise water table
- Reducing groundwater pollution
- Improving the quality of groundwater
- Reducing the soil erosion
- Supplementing domestic water requirement during summer and drought
Name the primary and secondary sources of water
Primary - rain
Secondary - rivers, lakes, groundwater
Name the water-conserving mechanisms that our ancestors followed
- People harvested rainwater by collecting water from the rooftops and storing it in tanks built in their courtyards. From open community lands, they collected rainwater and stored it in wells
- They harvested water runoff by capturing water from swollen streams during the monsoon season and storing it in water bodies
- They harvested water from flooded rivers
What was the water receptacle called in Western Himalayas?
Khatri or Kuhl
What was the water receptacle called in the Gangetic Plains?
Baolis or Dighis
What was the water receptacle called in Central India?
Johads
What was the water receptacle called in Ladakh?
Zing
What was the water receptacle called in the Eastern Ghats?
Korambu
What was the water receptacle called in the Deccan Plateau?
Bhandaras or Kere
What was the water receptacle called in the Western Ghats?
Surangam
What is the annual rainfall of India?
1,170 mm (46 inches)
what is the world average of India?
800 mm (32 inches)
Why do places even like Cherrapunji suffer from acute shortage of drinking water?
Rainfall in India occurs in short spells of high intensity. Due to such intensities and the short duration of heavy rain, most of the rain falling on the surface tends to flow away rapidly, leaving very little for the recharge of groundwater. This makes most parts of India experience a lack of water even for domestic uses
Name the elements of water harvesting
- Catchments
- Conduits
- Storage facility
- Recharge Facility
What is the catchment of water harvesting?
The surface which receives rainfall directly