Spring Rehabilitation at Gaurikund, Central Himalaya, India
The geothermal spring at Gaurikund is located in Himalayan Geothermal Belt in the Garhwal Region of Uttarakhand, India. Gaurikund town is situated along the trekking route to the famous Kedarnath temple, which was severely affected by a flood disaster in 2013, which caused huge damage to infrastructure and loss of more than 5000 human lives. Rehabilitation of Gaurikund geothermal spring is a priority due to religious beliefs, balneotherapic values and the opportunity it offers to understand the hydrological and geothermal characteristics of the region. To justify these aspects, an integrated study on geology, hydrogeology, hydrochemistry, geophysics, and remote sensing was taken up at Gaurikund. The geological studies indicate that the geothermal spring is recharged by steep, southerly dipping joints in granite gneiss. Subsequenetly, the deep percolated water heats up due to high geothermal gradient and advection to finally emerge along the Vaikrita Thrust and its sympathetic minor fault-thrust system. Four outlets of the spring were inventoried, with discharge varying from 7.46 to 95.54 L/ min. Two dimensional Electrical Resistivity Tomography using Wenner, Schlumberger and Gradient configurations revealed two low resistivity zones proximal to the geothermal spring, on the right bank of Mandakini river. Maximum kinetic temperature images generated using the normal emissivity model using the pre and post-disaster satellite data shows positive correlation between land surface temperature and spring discharge variation. Engineering interventions by bank protection and construction of small gully plugs in the catchment area is recommended along GaurikundSonprayag section on the right bank of Mandakiniriver.