Disaster management strategy for potential slide zones of Kumarkhera in Narendra Nagar township of Tehri Garhwal district, Uttarakhand, India
The present communication attempts to highlight the impending disaster in Kumarkhera locality of Narendra Nagar township, due to the existence of potential slide zone, and unplanned construction activity (for business interests), on a vulnerable slope in the area, during recent years. This communication also takes note of the fact that although the hamlet town of Narendra Nagar remained the administrative focal point for Tehri Garhwal region during a larger part of twentieth century, yet the selection of safe sites for residential, commercial and administrative purpose was a praiseworthy disaster management practice which has gradually been abandoned during past three decades or so. Furthermore, a detailed account of the landslide scenario, causative factors, and management strategy for the area, has also been explained in this article. Quickbird satellite images were downloaded from: http://earth. google.com and analysed for visualization and interpretation of terrain features, land use pattern and anthropogenic activities in the area. Field investigations were also carried out and factors such as terrain conditions, hazard scenario, land use regulations and people’s participation were considered while formulating a disaster management strategy for the area. Traditional disaster management vis-à-vis unplanned construction for business interests in recent years The area under investigation (Kumarkhera) lies in the Earthquake High Damage Risk Zone IV. The elements of earthquake resistance can be seen in the well-ordered old civic buildings of the neat little royal township of Narendra Nagar. Some of the buildings like the hospital and the secretariat are still in use today. The bazaar buildings too are a century old. The people of the area were also aware of the major hazards, namely landslides and flash floods in this part of Himalaya. This is evident by relatively safe habitation sites of Narendra Nagar from the threat of landslides, as the Disaster management strategy 361 Plate 3. A 3-D view of Kumarkhera area based on satellite image. Potential slide prone area with old slide scarp and toe of the old slide (on which present habitation of Kumarkhera in located) are also seen in the image
DPM 19,3 362 Plate 4. A field view of old slide zone of Kumarkhera with few small active slide scarps seen on the concave slope in the immediate downslope of old slide scarp and further upslope of Kumarkhera locality hamlet town rarely witnessed losses due to landslides in the past. Contrary to this rich heritage of traditional disaster management, the habitation of Kumarkhera has emerged probably over an old slide zone (see Plates 1-5). Very high degree of risk to which Kumarkhera is exposed is a consequence of haphazard and unplanned growth of residential, commercial (shops) and residential cum commercial area with in a high hazard zone (see Plates 1-3). Landslide scenario Kumarkhera with a floating population of about 450 is witnessing slow flowage in the form of creep and subsidence. Rapid flowage in the form of two active slide zones is also observed in the area (see Plates 1-5). This settlement is also subjected to bank erosion by two small seasonal streams, which drain through it. One shop was damaged due to ground subsidence in 2003 (see Plate 6). The incessant rains during the coming monsoons may further cause severe damage to Kumarkhera. Monsoon season is also the pilgrimage season in Uttarakhand state as the snow melts from the Hindu shrines located in higher Himalaya and since Kumarkhera is located on Rishikesh - Gangotri National Highway the convoys of vehicles carrying pilgrims heading to the famous shrines of Gangotri and Yamunotri pass through this area since early in the morning upto evening. Furthermore, most of the shops are open during the daytime and floating population of shopkeepers and customers is in and around the shops. This increases the risk element in this area particularly during the daytime as the floating population of pilgrims and shopkeepers is also exposed to risk. A part of this residential cum commercial area is witnessing slow flowage as evident by the bulging of ground in the immediate downslope of the Highway. Some small slide zones are also developed within the large old slide zone of Kumarkhera.