A Threatened Survival
The hydrological system of Kashmir region (Indus River Basin) is highly dependent on the winter precipitation (snowfall) brought by Western Disturbances. The Western Disturbances originate from Mediterranean Sea/Atlantic Ocean, bring more than 70 per cent annual precipitation to Kashmir region. In every winter (November to March) snow gets accumulated and redistributed across the catchments and basins and becomes a natural water reservoir. The accumulated winter snow acts as a seasonal natural locking system, which melts with the increasing ambient temperature and releases meltwater thereby regulating the hydrological systems. The meltwater so generated plays a significant role in sustaining the flow in the streams and springs, and recharging groundwater throughout the year. In glacierized basins, melting of glaciers sustains the hydrological flow, when the seasonal snowpacks exhaust around August/September. However, in winter it is the groundwater which maintains the flow of the streams as it exits as base flow in the form of seepages and springs. Regular rainfall throughout the year is a top up pack to the hydrological system which helps in the increase in surface and groundwater storage. This is how the hydrological system in the Kashmir Himalaya works.
However, the climate change is evident and penetrative across the globe, which is more pronounced in the Indus River Basin, that has already impacted the hydrological dynamics of the region. Although climate change is considered as gradual, but in last 2-3 decades it has significantly affected the temperature and precipitation regimes of the Himalaya especially the Kashmir Himalaya. It has been observed that the strength and frequency of the Western Disturbances has decreased for last 2-3 decades. Even some Western Disturbances enter the Kashmir Himalaya without any precipitation, which is still least understood phenomenon. This has led to many changes in the hydrological processes and dynamics in the region. Drying up of springs is one of the prominent indications and examples of the global climate change. During the last few decades, in the Himalayas, some springs have already dried up, many have attenuated discharge and some perennial springs have become seasonal.
In Kashmir, we have many types of springs including karst springs (e.g., Achablanag, Kokernag, Verinag, Martandnag, etc), Alluvial springs and Karewa springs. The studies conducted at University of Kashmir by our research group over the years suggest that besides climate change, the anthropogenic activities also play a significant role in influencing the spring discharge. We have observed that some springs in Kashmir have dried up and many others have attenuated the spring flow due to anthropogenic activities including puncturing of aquifer by deepening of river/stream bed through mechanical dredging for sand/boulder, narrowing the stream/river width for construction of roads, replacing the gabion with concrete bunds along river/stream bunds, unabated well development resulting in overexploitation of groundwater, etc.
The recent drying up of historic Achabal Naag, built by Noor Jahan in the 17th century at the famous Achabal Mughal Garden, and other springs, is an area of grave concern. Exiting at the foothills of highly karstified ridge, the spring is dominantly recharged by Brangi stream at Argam-Develgam. The hydrological system is so connected through karst features that the recharging water takes less than one day to reach the spring point. Karst landscapes are characterized by sinkholes, sinking streams, conduits, caves, and springs, which integrate surface and subsurface drainage. We have observed that increase in flow of Brangi Nala and melting of snow or rainfall in the karstified hill behind the spring immediately increases the flow of the Achabal Naag.
That is why Achabal Naag is highly fluctuating with discharge ranging from a few liters per second to a few cubic meters per second. At the same time, it reflects how vulnerable it is to climate change or any anthropogenic activity. It is well understood that karst ecosystems are highly fragile environments that are suffering a progressive degradation caused by human activities. Urbanization, deforestation and quarrying in catchments have disturbed, and partially or totally destroyed the karst landscape causing modification of the surface and underground karst system and deterioration in the water quality. We have observed high nitrate and coliform bacteria in these springs reflecting the human activities in the recharge areas or its pathways.
There could be many reasons for the recent drying up of the karst spring and lack of snow at lower altitudes of the catchment seems to be a stronger one. It is important to understand that there is about 80 per cent snow deficit this winter in the Kashmir Himalaya. While looking at google images of the region we notice that high altitudes (>3000m asl) are fully snow covered (although thin) but lower altitudes (~2000 m asl) are snow free. The spring discharge data of karst springs of Kashmir suggest that the spring flow starts increasing by early to mid February, by the slight increase in ambient temperature resulting in melting of low altitude snow during day time. However, the lack of snow at lower altitudes this winter and lack of rainfall has resulted in drying up of the karst springs. The temporary phase of drying up of Achabal Naag and other springs came to an end by the recent rain and snow.
The over exploitation of groundwater decreases the water table, that could also influence the spring flow. The emergence of sinkhole in the recharge area of the Achabal Naag in February 2022 and its treatment perhaps taken in haste without foreseeing its consequences in the long run, has resulted in an unusual hydrological response of the spring: reduction of spring flow, a marked rise in the water level approximately a month later, could have diverted some underground conduit flow, could also be another subtle reason for the drying up of the spring.
The temporary drying up of the Achabal Naag and other springs in February and snow deficit of ~80 per cent is a wake up call for the people and administration. If there would not be regular rainfall events throughout the year there will be more and more shortage of water and many more springs will temporarily dry up. Through this article I want to convey to the people of Kashmir to use water judiciously and not to waste it, as we will be experiencing temporary water shortages this year and years to come.
Understanding hydrology, hydrodynamics and water quality of all water resources in Upper Indus Basin including springs is a major thrust area of research in the University of Kashmir. We are monitoring the major springs for last two decades. As per our data, most of the karst springs showed a significant decreasing trend in the flow (except Martand Naag). We have identified the recharge areas of many springs. Therefore, to regulate the flow of the springs we need to apply state of art civil interventions in the recharge areas. Besides, a comprehensive hydrogeological study is warranted to map the underground karst features and monitor the springs in real time,in order to ensure the sustainability of these precious hydrological resources of the Kashmir region.
Prof. Ghulam Jeelani, Dean School of Earth & Environmental Sciences, University of Kashmir
