Understanding environmental change and disaster risk in the Himalayas

Recent heavy rains in Nainital, Northern India, have focused attention on issues that are being addressed by two ESPA projects. The ESPA project “The Political Economy of Water Security, Ecosystem Services and Livelihoods in the Western Himalayas” has been studying the importance of land use planning and zoning to ensure the maintenance of areas that are ecologically sensitive and critical to the region’s water security. The ESPA Fellowship “Ecosystem Services and Disaster Risks in the Western Himalayas” is particularly timely in the aftermath of the Nepal earthquake and recent landslides in the case study town of Nainital have raised awareness of local disaster management needs in the entire Himalayan region. 

 

Photo Credit: Rajiv Dubey

 

Every year, by the beginning of July, the monsoon starts pouring down on the hill station of Nainital, Uttarakhand. It marks the end of the peak tourist season in which the population of the town more than doubles. This year, the monsoon started with an “extreme” weather event. Whereas the normal daily rainfall in monsoon is 65.9 mm, it rained more than 388mm over two days in early July. Although it is difficult to attribute single weather events to climate change, the general trend in the region in recent years is that rainfall patterns are changing. Heavy or very heavy rainfall events are increasing while moderate rainfall events are decreasing during monsoon. 

 

In the foothills of the Kumaun Himalayas, floods and landslides are the major threat arising from heavy rain. In June 2013, for example, a pre-monsoon cloudburst that lasted for four days led to devastating floods in wide parts of the Indian states of Uttarakhand and Himachal Pradesh, and resulted in an estimated 5000 fatalities. Nainital itself has a long history of landslides. The first landslide in Nainital was recorded in 1866 when the town already had developed into a popular summer retreat of British soldiers and colonial officers. After a major landslide in 1880, the British constructed a drainage system (79km in length) to decrease the water pore pressure during the monsoon rains. After the construction of the drains was completed in 1885, another dozen landslides occurred in Nainital town – half of them in the 1980s and 1990s during the course of heavy construction. The last major landslide of 1998 caused no casualties in the town, and in recent years residents have been more affected by landslides that disrupt the road network in the hilly district than by landslides in Nainital itself. 

 

Most drains are still in place and local environmentalists regard them as “arteries and veins of the town” that need to be maintained and cleaned properly at all times (Times of India, 08/07/2015). As a consequence of a Public Interest Litigation (PIL) that was filed in 2012, the High Court in Nainital ordered the removal of encroachments over the drains last year. The forced clearance of these encroachments by owners of nearly 50 residential houses or hotels allowed the drains to perform this vital function, and might have averted major loss of life and property when heavy rain hit Nainital last week. 

 

Last week’s heavy rains increased the water level of Nainital Lake by two metres and caused two minor landslides within one week, damaging numerous houses on one of the hillslopes. The recent landslide occurrences exhibit the relevance of my ESPA-funded project “Ecosystem services and disaster risks in the Western Himalayas: an integrated participatory modelling approach using Bayesian Networks”. During this ESPA Fellowship, I will develop Bayesian Networks to support local disaster management in Nainital. For this, I will apply Bayesian Networks in three ways:

As recent events in the Himalayas have demonstrated, ESPA-funded projects are focused on providing the key scientific and research insights that are needed to address the links between ecosystems, poverty and well-being, and vulnerability, in one of the most ecologically fragile and important regions of the world.