Aquifer Mapping & Management

• 24 Dec 2020

Why in News

A Memorandum of Agreement (MoA) has been recently signed between Central Ground Water Board (CGWB), Ministry of Jal Shakti and Council Of Scientific And Industrial Research–National Geophysical Research Institute, for use of advanced heliborne geophysical survey (through helicopter) and other scientific studies under the Aquifer Mapping Programme.

• Geophysical data is used to provide information on the physical properties of the Earth's surface and subsurface. As a result, geophysical data can help locate hydrocarbons, minerals, aggregate, and other natural resources.
  
  • For example groundwater mapping, mineral mapping.

Key Points

• Objectives of the study:
  
  • High resolution aquifer mapping using heliborne geophysical studies, including identification of sites for artificial recharge.
    
    • The main advantages of the Heliborne geophysical survey is that it is fast, highly data dense, precise and economical.
  • Create 3D Geophysical model, geophysical thematic maps at horizontal and vertical plains.
  • Aquifer Geometry of principal aquifer with demarcation of de-saturated and saturated aquifers.
    
    • The rocks in which groundwater is stored are called aquifers. They are typically made up of gravel, sand, sandstone or limestone.
  • Spatial and depth wise distribution of paleochannel network if any and its linkage with the aquifer system.
    
    • A palaeochannel, or paleochannel, is a remnant of an inactive river or stream channel that has been filled or buried by younger sediment
  • Selecting suitable sites for groundwater withdrawal and water conservation through artificial or managed aquifer recharge.
  • The study is likely to generate groundwater data in a very short time period helping in groundwater management by preparing site specific plans for improving ground water levels in water stressed areas.

India and Groundwater

• India is the largest user of groundwater in the world, extracting groundwater to the tune of 253 billion cubic meter (bcm) per year.
  
  • It is about 25% of the global groundwater extraction.
  • Out of the total of 6584 assessment units, 1034 have been categorized as ‘Over-exploited’, 253 as ‘Critical’, 681 as ‘Semi-Critical’ and 4520 as ‘Safe’.
  • The remaining 96 assessment units have been classified as ‘Saline’ due to non-availability of fresh groundwater due to salinity problems.
• Availability of Water:
  
  • India has about 1123 billion m³ of water resources available, out of which 690 bcm is surface water and rest 433 bcm is groundwater.
  • Out of total groundwater available, 90% of it is used for irrigation purposes which is mainly for agricultural purposes.
  • The remaining 10% accounts for domestic and industrial purposes combined.
• Water Crisis in India:
  
  • According to the Composite Water Management Index (CWMI) report released by the NITI Aayog in 2018, 21 major cities (Delhi, Bengaluru, Chennai, Hyderabad and others) are racing to reach zero groundwater levels by 2020, affecting access for 100 million people.
    
    • The CWMI report also states that by 2030, the country's water demand is projected to be twice the available supply, implying severe water scarcity for hundreds of millions of people and an eventual 6% loss in the country's GDP.
  • Maharashtra and nearly half the country is facing an acute water shortage. Besides Maharashtra, Tamil Nadu, Karnataka, Rajasthan, parts of Gujarat, Punjab and Haryana are facing a water shortage of unprecedented levels.

National Aquifer Mapping and Management program (NAQUIM)

• It is being implemented by the Central Ground Water Board (CGWB).
• NAQUIM envisages mapping of aquifers (water bearing formations), their characterization and development of Aquifer Management Plans to facilitate sustainable management of groundwater resources.
• NAQUIM was initiated as a part of the Ground Water Management and Regulation Scheme to delineate and characterize the aquifers to develop plans for ground water management.

Central Ground Water Board

• It is a subordinate office of the Ministry of Jal Shakti, and is the National Apex Agency entrusted with the responsibilities of providing scientific inputs for management, exploration, monitoring, assessment, augmentation and regulation of groundwater resources of the country.

CSIR-National Geophysical Research Institute

• The National Geophysical Research Institute (NGRI) is a geoscientific research organization established in 1961 under the Council of Scientific and Industrial Research (CSIR).
• HQ: Hyderabad

Source: PIB