Increased rainfall alone will not help groundwater recovery

No Comments

Subject :Geography

Section: Indian geography

Context:

Rapid groundwater depletion in north India has become a norm during the last few decades.

Groundwater exploitation:

Between 2002 and 2022, about 95% of India’s groundwater depletion occurred in north India.
Groundwater use and summer monsoon rainfall variability are the two main drivers of groundwater storage.
The evapotranspiration has increased due to the warming climate, which will further limit water availability for groundwater recovery.
Groundwater exploitation for irrigation purposes is still the main cause of groundwater depletion.
Excessive pumping from nonrenewable groundwater storage will aggravate groundwater loss.

Status of Groundwater Depletion in India:

According to the CGWB, with 230 billion metre cubes of groundwater drawn out each year for irrigating agricultural lands in India, many parts of the country are experiencing rapid depletion of groundwater.
The total estimated groundwater depletion in India is in the range of 122–199 billion metre cubes.
89% of ground water extracted is used in the irrigation sector, making it the highest category user in the country.
This is followed by groundwater for domestic use which is 9% of the extracted groundwater. Industrial use of ground water is 2%.50% of urban water requirements and 85% of rural domestic water requirements are also fulfilled by groundwater.

Recovery of depleted groundwater:

The warming climate will also increase the amount of summer monsoon rainfall that north India will receive, and the enhanced precipitation could help the recovery rates of groundwater.
Gravity Recovery and Climate Experiment (GRACE) data shows that the increased monsoon rainfall due to a warming climate is not enough for the recovery of depleted groundwater due to irrigation purposes.
As per climate projection, the summer monsoon rainfall is projected to increase by 6-8%, and this increase is expected to help recover the lost groundwater.
But even in the most optimistic scenario, the highest projected groundwater recovery (about 260 cubic km) in the near period (2021-2040) will only help recover about 50% of groundwater lost in the last two decades.
Effects of drought:
- While the impact of droughts at longer frequencies may be less, consecutive years of drought can adversely affect groundwater storage as recharge will be less while extraction of groundwater for irrigation will be higher than when summer monsoon rainfall is normal.
- There is a compulsion to make irrigation more efficient and shift crop growing and procuring areas.

Some initiatives taken by the government to reduce and recover the groundwater resources in India:

It is promoting the concept of conjunctive use of surface and groundwater based on the village/gram panchayat level water security plan prepared in a scientific manner through the participation of communities/stakeholders.
Atal Bhujal Yojana (Atal Jal): It is a Rs. 6000 crore Central Sector Scheme with World Bank assistance, for sustainable management of groundwater resources with community participation.
Jal Shakti Abhiyan (JSA): It was launched in 2019 in 256 water-stressed districts in the country to improve water availability including groundwater conditions in these areas.
- It has a special emphasis on the creation of recharge structures, rejuvenation of traditional water bodies, intensive afforestation etc.
Aquifer Mapping and Management Programme: The CGWB has taken up Aquifer Mapping and Management Programme.
- The program is aimed to delineate aquifer disposition and their characterization for the preparation of aquifer/area-specific groundwater management plans with community participation.
Atal Mission for Rejuvenation and Urban Transformation (AMRUT): The Mission focuses on the development of basic urban infrastructure in the AMRUT cities, such as water supply, sewerage & septage management, stormwater drainage, green spaces & parks, and non-motorized urban transport.