Understanding the historical, technical, and local perception of displacement activity in Joshimath town of Uttarakhand, India

The study highlights the current situation of displacement activities in Joshimath town of Uttarakhand Himalayas. Positioned in the vicinity of Viakrita and Pandukeshwar thrust, the town is situated on an old landslide and glacial moraine material, and rests on giant gneiss boulders embedded in loose sand matrix (Bhattacharya et al, 1982). Consequently, the slopes are prone to movements like mass wasting and related land subsidence. Moreover, the decadal rise in population, unplanned infrastructure, and toe cutting from Dhauli Ganga river has exacerbated the immense pressure on the already vulnerable slopes.

Thus, to understand the cause-impact and the current situation of displacement activity in Joshimath town, the historical and technical findings by previous studies were assessed with respect to the present on-ground situation of displacements and compared to the people’s perception of these disturbances. The historical evidence suggests that slope creep and related subsidence in Joshimath dates from the1960’s and has since been reappearing (Sati et al. 2023). Different technical studies have linked the cause of displacements in Joshimath to land subsidence, groundwater fluctuation and infrastructure overburden with less stress on the landslide displacement being the primary factor. Thus, a comprehensive mapping of landslide scars was done, and it was found that the recorded ground cracks and damaged buildings corresponded well with the mapped landslide scars. The recent field studies conducted in December 2023, suggested that people of Joshimath are not unaware of the landslide activities along the rim regions of Joshimath slope, and at least two communities in the past had to relocate to uphill areas, due to increased toe cutting and slope destabilization along Dhauli Ganga River. Moreover, according to the locals, slope destabilization and related subsidence in Joshimath was exacerbated post the 7^th Feburary 2021 debris flow and successive heavy rainfall events in October 2021. Satellite images also suggest the reactivation of old landslides due to toe cutting after the 2021 event and similar destabilization was also triggered post the 2013 flash floods (Sharma et al., 2014). The field observations also highlighted the presence of new cracks and fissures on roads, fields, and repaired constructions. Thus, the increase in toe cutting, followed by slope failures may lead to upslope progression of landslide scars. Also 99% of buildings in Joshimath are non-compliant with the national building codes of 2016, and most of the adversely affected buildings lie in regions on steep slopes of hill (CBRI, 2023). Consequently, the unplanned infrastructure development along such unstable old landslide scars could accelerate slope instability.

Keywords: Displacement, Landslides, cracks, toe-cutting, infrastructure