Preprints
https://doi.org/10.5194/egusphere-2023-1975
https://doi.org/10.5194/egusphere-2023-1975
27 Oct 2023
 | 27 Oct 2023
Status: this preprint is open for discussion.

More than one landslide per road kilometer – surveying and modeling mass movements along the Rishikesh-Joshimath (NH-7) highway, Uttarakhand, India

Jürgen Mey, Ravi Kumar Guntu, Alexander Plakias, Igo Silva de Almeida, and Wolfgang Schwanghart

Abstract. The rapidly expanding Himalayan road network connects rural mountainous regions. However, the fragility of the landscape and poor road construction practices lead to frequent mass movements along-side roads. In this study, we investigate fully or partially road-blocking landslides along the National Highway (NH-7) in Uttarakhand, India, between Rishikesh and Joshimath. Based on an inventory of >300 landslides along the ~250 km long corridor following exceptionally high rainfall during September and October, 2022, we identify the main controls on the spatial occurrence of mass-movement events. Our analysis and modeling approach conceptualizes landslides as a network-attached spatial point pattern. We evaluate different gridded rainfall products and infer the controls on landslide occurrence using Bayesian analysis of an inhomogeneous Poisson process model. Our results reveal that slope, rainfall amounts, lithology and road widening are the main controls on landslide occurrence. The individual effects of aggregated lithozones are consistent with previous assessments of landslide susceptibilities of rock types in the Himalayas. Our model spatially predicts landslide occurrences and can be adapted for other rainfall scenarios, and thus has potential applications for efficiently allocating efforts for road maintenance. To this end, our results highlight the vulnerability of the Himalayan road network to landslides. Climate change and increasing exposure along this pilgrimage route will likely exacerbate landslide risk along the NH-7 in the future.

Jürgen Mey et al.

Status: open (until 05 Jan 2024)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse

Jürgen Mey et al.

Viewed

Total article views: 173 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
126 40 7 173 13 3 4
  • HTML: 126
  • PDF: 40
  • XML: 7
  • Total: 173
  • Supplement: 13
  • BibTeX: 3
  • EndNote: 4
Views and downloads (calculated since 27 Oct 2023)
Cumulative views and downloads (calculated since 27 Oct 2023)

Viewed (geographical distribution)

Total article views: 173 (including HTML, PDF, and XML) Thereof 173 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Discussed

Latest update: 06 Dec 2023
Download
Short summary
The Himalayan road network links remote areas, but fragile terrain and poor construction lead to frequent landslides. This study on NH-7 in India's Uttarakhand region analyzed 300 landslides after heavy 2022 rainfall. Factors like slope, rainfall, rock type, and road work influence landslides. The study's model predicts landslide locations for better road maintenance planning, highlighting the risk from climate change and increased road use.