In December 2023, a remarkable incident occurred in Mohangarh, Rajasthan. During a tubewell drilling operation, water suddenly gushed out, sparking speculation about the ancient Saraswati River’s return. However, experts clarified that this phenomenon was due to an artesian well, a natural water source under pressure. This event marks the geological complexities of Rajasthan’s water resources.
About Artesian Wells
An artesian well is a type of well where water rises to the surface without mechanical pumping. This occurs when groundwater is trapped between impermeable layers of rock or sediment. When a borehole penetrates this layer, the pressure causes water to flow upwards. This natural pressure can create impressive water spouts, especially in arid regions like Rajasthan.
Geological Context in Rajasthan
Rajasthan is characterised by its desert landscape, with groundwater resources hidden beneath the surface. The state has numerous aquifers, which are geological formations that can store and transmit water. These aquifers can be confined, meaning they are surrounded by impermeable layers that maintain pressure. The recent incident in Mohangarh involved such a confined aquifer, leading to the unexpected water spout.
The Mohangarh Incident
On December 28, workers drilling a tubewell reached a depth of 850 metres when water erupted from the ground. This was likely due to a breach in the sandstone barrier that held the water under pressure. The water flow lasted for nearly three days before stopping. Experts confirmed that this event was not linked to the Saraswati River but was a natural occurrence related to the local geology.
Safety and Environmental Considerations
Following the water spurt, concerns arose regarding safety and environmental impact. Officials assured residents that the water was safe and that the associated gases found were non-flammable and non-hazardous. Continuous monitoring and testing were conducted to ensure public safety. The presence of gases was noted as unusual but not dangerous.
Future Investigations and Surveys
In light of this incident, the Union Minister for Science and Technology announced plans for further investigations. Scientists from the Council of Scientific and Industrial Research (CSIR) will conduct detailed surveys to identify more underground aquifers in Rajasthan. Advanced scanning equipment will be used to map these resources effectively.
Importance of Sustainable Water Management
The Mohangarh incident puts stress on the need for sustainable water management in desert regions. About and mapping underground water resources can help in planning and conservation efforts. As Rajasthan faces water scarcity challenges, harnessing these natural aquifers could provide vital resources for local communities.
Questions for UPSC:
- Discuss the significance of artesian wells in arid regions. What role do they play in local ecosystems?
- Critically examine the geological factors that contribute to the formation of aquifers in desert landscapes.
- Explain the potential environmental impacts of drilling activities on groundwater resources.
- With suitable examples, discuss the importance of advanced technologies in identifying underground water sources.
Answer Hints:
1. Discuss the significance of artesian wells in arid regions. What role do they play in local ecosystems?
- Artesian wells provide a natural source of freshwater in arid regions, crucial for agriculture and drinking water.
- They support local ecosystems by maintaining soil moisture and enabling vegetation growth despite low rainfall.
- These wells can sustain wildlife habitats by providing necessary water sources in otherwise dry environments.
- They help recharge surrounding aquifers, promoting groundwater sustainability and resilience against drought.
- Artesian wells can also influence local climate conditions by contributing to humidity levels in the area.
2. Critically examine the geological factors that contribute to the formation of aquifers in desert landscapes.
- Aquifers form in desert landscapes primarily due to the presence of permeable rock layers, such as sandstone, that can store water.
- Geological formations often include impermeable layers above aquifers, which trap water under pressure and create artesian conditions.
- Desert regions may experience infrequent but intense rainfall, allowing water to infiltrate and replenish aquifers.
- Geological processes, such as tectonic activity, can create fractures and faults that enhance water storage capacity.
- Human activities, like drilling, can also impact the natural state of aquifers, leading to changes in water pressure and availability.
3. Explain the potential environmental impacts of drilling activities on groundwater resources.
- Drilling can lead to contamination of groundwater if pollutants from the surface seep into aquifers.
- Excessive drilling may deplete groundwater resources, leading to reduced water availability for ecosystems and communities.
- Drilling activities can disrupt natural water flow and pressure, affecting the stability of aquifers.
- Increased drilling can result in land subsidence, where land sinks due to the removal of water from underground sources.
- Monitoring and regulation are essential to mitigate negative impacts and ensure sustainable groundwater extraction.
4. With suitable examples, discuss the importance of advanced technologies in identifying underground water sources.
- Advanced technologies like remote sensing and geophysical surveys allow for mapping aquifers without invasive drilling.
- Heliborne surveys, as used in Rajasthan, can identify geological formations that host water resources effectively.
- Ground-penetrating radar (GPR) can provide detailed images of subsurface structures, aiding in locating aquifers.
- Satellite imagery helps in assessing surface water bodies and predicting groundwater recharge areas.
- Utilizing these technologies can enhance water resource management, particularly in arid regions facing scarcity.
