In the last decade, availing water from springs has become increasingly difficult in Sikkim. Springs are a point from where water flows out of aquifers to the earth’s surface and in rural Sikkim, they are the major source of water for domestic and irrigation purposes. While they remain dry in February, April and March, villagers, especially in southern and western parts of the state, told researchers, Manish Goyal and Adani Azhoni from IIT Guwahati, Assam, that they have become dry most of the time.
According to a 2017 report by NITI Aayog, the springs dried up because of increasing surface run off, caused by increase in water demand, changing land use patterns and ecological degradation. Besides, over the last few decades, the state’s water vulnerability has increased due to climate change.
Read our coverage on climate change impacts on Himalayas
In 2009, Sandeep Tambe, from the state government’s Rural Department started Dhara Vikas, a springshed rejuvenation programme to revive and maintain the drying springs and lakes particularly. Villagers feel that it has improved the availability of water. Spring water rejuvenation means trapping the surface runoff during monsoons to enable its percolation into the ground by digging trenches and ponds.
However, an upcoming study by Goyal and Azhoni says that there is a lack of scientific study to back up the claim that spring rejuvenation has, in fact, improved the water availability. This holds significance because the states of Himanchal Pradesh, Uttarakhand and Meghalya are planning to adopt such a method and delegates from Nepal, Bhutan have vistited the state to understand it. In 2017, Centre announced it would carry surveys to track lost springs in Himalayas with the view to solve the water crisis by reviving aquatic resources. It will cover a region stretching from Jammu and Kashmir to north eastern states and would include 10 hill states.
In an interview with Down To Earth (DTE), Goyal said, “It is extremely critical to undertake various studies to understand the challenges of adopting spring water recharge as a climate change adaptation especially when other states are also planning to adopt such methods” (see full interview below).
To be published in Elsevier in June, the study about climate change diagnosis and adaptation strategies warns that increased infiltration due to the rejuvenation can result in potential landslides by altering pore pressure. But the authors also add that landslides depend on other factors not just infiltration and hence call for further research.
When DTE asked Tambe, currently Professor at Indian Institute of Forest Management, Bhopal, about his views on the study, he said that he agreed with the authors that more intensive instrumentation and scientific monitoring of spring revival is needed. “Plans are on the anvil to instrument a few springs and streams and set up spring observatory for long term monitoring of the spring hydrology in partnership with United Nations Development Program,” he added. Dhara Vikas was later launched under the Mahatma Gandhi National Rural Employment Guarantee Act with assistance from World Wide Fund For Nature and People’s Science Institute, Dehradun, Uttarakhand.
‘Locals acknowledge their ignorance regarding the actual impact of spring water rejuvenation’
The author spoke with Manish Kumar Goyal, Associate Professor, Discipline of Civil Engineering, Indian Institute of Technology, Indore and co-author of the study
Q. You talk about spring water rejuvenation in your article and how there is a lack of scientific study to back up the claim that it has, in fact, improved the water availability. Please elaborate.
As reported in our paper, spring water rejuvenation is being taken up by the Sikkim government as an important strategy to improve/maintain the sustainability of water in the study area. In this regard, scientific studies that can inform the locals about the actual quantifiable improvement made by these kinds of projects will be helpful. Moreover, studying the geological strata to identify the suitable locations of intervention will be helpful.
Q. What sort of scientific studies?
Empirical studies that demonstrate the effect of digging trenches on mountain tops to increase the rainwater infiltration on the spring water outflow.
Q. Regarding maladaptation, what do you think are the potential negative impacts of spring-shed development? Especially, considering the local terrain and its disaster prone nature.
This, we believe, is an area that has not been explored adequately. Since the mountain terrains in this area are steep and prone to landslides, the increased infiltration could increase the pore pressure leading to potential landslides. But since the occurrence of landslides depends on so many other factors, we believe further investigative studies will be helpful for the area.
Q. Has spring shed development actually backfired anywhere in the world?
We have no knowledge of such studies that have been undertaken and hence perhaps it is an area that can be explored.
Q. According to your article, locals opine that spring water rejuvenation has actually helped them. Were there any contradictory views among the locals? Did locals identify any problems associated with the same?
As reported in our study, the locals whom we have interviewed were particularly enthusiastic about the spring water rejuvenation project being carried. There were no contradictory views or problems identified by the locals (if there were any we would have reported in the paper). However, they also acknowledged their ignorance regarding the actual impact or the mechanism.
Q. What suggestions would you give with respect to Spring Water Rejuvenation and its associate impacts?
We believe this is an important and urgent area of research and hence, requires the involvement of various expertises to understand the mechanism, particularly geotechnical researchers. It would be interesting to trace the source of the spring water (that emerges naturally in the foothills of the mountain) and the capacity of the mountains to store the water.
In a 2013 study published in India Mountain Initiative, co-author Tambe wrote how springs and streams remain largely understudied in India. For instance, all major Himalayan revivers have been instrumented and their discharge monitored but historical discharge data of spring and streams are unavailable and unrecorded. There can be various reasons for this, such as insufficient data, limited human dependency and greater effort needed to understand this scattered resource.
There are few studies available on declining Himalayan springs in states of Uttarakhand and Sikkim. However, in North-western Himalaya (J&K, Himachal Pradesh, and Arunachal Pradesh), Central Himalayas (Nepal) and in Eastern Himalayas (Bhutan and Arunachal) are yet to adequately studied.
Read our cover story on the lack of data on glaciers