LandslidesLandslidesLandslidesLandslides

St. Mary`s SchoolSt. Mary`s School

AcknowledgementAcknowledgementAcknowledgementAcknowledgement

● Presentation development team:- Class ix Group 4

● Members:- Editor 1. Al Muktadir

Hussain 2. Tuman Paul 3. Promfila Chetry 4. Ankita Baishya 5. Raju Chetry 6. Nazisha Afreen 7. Saurav Saha 8. Biswajit datta 9. Sohail Ahmed

Designers

Coordinators

PrefacePreface

In a country like India which is extremely disaster prone, it is needless to emphasize the important role that teachers and students can play in creating awareness in communities and reaching vital information to them. It is not uncommon to find that a school teacher or student has become a model disaster manager for a community that has faced a severe disaster in the recent past. They have done appreciable work in generating an awareness about local disaster vulnerabilities. We as students can do many activities for reducing disasters and taking preventive measures.

We, the members of Community Emergency Response Team (i.e., an imaginary committee associated by group 4 of class ix) have prepared a report on landslides. We have also prepared a short note on the recent accounts of landslides and also prepared their impact on communities.

we would like to thank Sr. Solly, our disaster management teacher for guiding in making his presentation a better one.

Landslides in indiaLandslides in india

● Landslide, a frequently occurring natural hazard in the hilly terrains of India, shows preponderance of activity during the monsoon period from July to September and after the snow fall from January to March. The strong earthquakes also cause triggering of landslide, particularly in regions marked by critically disposed and unstable slopes. On a rough estimate, nearly 15% of India’s landmass or 0.49 million sq km area is prone to landslide hazard. This includes 0.098 million sq km of the North Eastern Region, comprising the Arakan Yoma ranges, and 0.392 million sq km of parts of the Himalaya, Nilgiri, Ranchi Plateau and Eastern & Western Ghats. As many as 20 States of India are affected by different degrees of landslide hazard. Of these, the States of Sikkim and Mizoram have been assessed to be falling under very high to severe hazard classes. Most of the districts of the States of Jammu & Kashmir, Himachal Pradesh, Uttarakhand, Arunachal Pradesh, Nagaland and Manipur come under high to very high landslide hazard classes. In the Peninsular Region, the hilly tracts of States like Karnataka, Andhra Pradesh, Tamil Nadu, Maharashtra, Goa, Madhya Pradesh and Kerala constitute low to moderate hazard prone zones.

What is Landslide?What is Landslide?What is Landslide?What is Landslide?

● Landslide refers to the downward sliding of huge quantities of land mass which occur along steep slopes of hills or mountains and may be sudden or slow. Landslides or a landslip is a geological phenomenon which include a wide range of a ground movement, such as rocks falls, deep failure of slopes and shallow debris, flows which can occur in offshore, coastal and on shore environment. Although the action of gravity is the primary driving for landslides to occur. Typically , pre- condition factors build up specific subsurface conditional and make the area slope prone to failure, whereas the actual landslide often requires a trigged before being relevealed.

A Landslide Is…A Landslide Is…A Landslide Is…A Landslide Is…

● A rapid shift in land mass Typically associated with

periods of heavy rainfall or rapid snowmelt.

Tends to worsen effects of flooding that often accompanies landslides.

● All movement of land masses are referred as landslides, but differ in many respects, therefore all types of landslides are categorized as Earth Movements.

● These are classified as

Classification of Earth MovementsClassification of Earth Movements

Earth Flow Landslides Subsidence

Solifluction

Creep

Rapid flows

Rock slides

Rock falls

Debris slide orslump

collapse

Plastic flow

Main causes of LandslidesMain causes of Landslides Main causes of LandslidesMain causes of Landslides

● Weak or sensitive materials ● Sheared, jointed, or fissured materials ● Adversely oriented discontinuity (bedding, schistosity, fault, unconformity, contact, and so

forth) ● Contrast in permeability and/or stiffness of materials ● Tectonic or volcanic uplift ● Fluvial, wave, or glacial erosion of slope toe or lateral margins ● Subterranean erosion (solution, piping) ● Deposition loading slope or its crest ● Vegetation removal (by fire, drought) ● Thawing ● Freeze-and-thaw weathering ● Shrink-and-swell weathering ● Excavation of slope or its toe ● Loading of slope or its crest ● Drawdown (of reservoirs) ● Deforestation ● Irrigation ● Mining ● Artificial vibration ● Water leakage from utilities ● The factors that cause most of the damaging landslides around the world are generally

combination of these.

Areas Prone to LandslidesAreas Prone to LandslidesAreas Prone to LandslidesAreas Prone to Landslides

● Existing old landslides● Bases of steep slopes● Bases of drainage channels● Developed hillsides where leach-field septic

systems are used

9

Uttarkashi ,India

Landslide effectsLandslide effectsLandslide effectsLandslide effects

● Natural calamities including earthquakes, landslides, avalanches, floods, cyclones, droughts and volcanic eruptions have been affecting mankind since beginning of civilization.

● These are believed to account for up to 4% of total annual deaths ● Distribution of casualties due to natural disasters is, however, not evenly distributed

around the globe. ● The impact of these disasters is more severe in developing countries which have

higher population densities. ● Globally, the landslides, a prominent natural disaster, are estimated to cause

approximately 1000 deaths annually apart from damaging property worth millions of dollars

● The landslides can be rapid or slow and occur in varied geological environs including underwater.

● The landslides account for considerable loss of life and cause damage to human settlements, civil structures, hydro projects, communication routes, and agricultural and forest land.

● The secondary effects of landslides could also be disastrous. These include the damage by impact of waves generated by landslides entering water bodies, formation of landslide dams resulting from blockade of drainage courses and consequent floods due to breaching/overtopping.

● Coseismic landslides are induced by earthquakes. Assam Earthquakes of 1897 & 1950, Kangra Earthquake of 1905, Uttarkashi Earthquake of 1991, Chamoli Earthquake of 1999 and Kashmir earthquake of 2005 induced widespread landslide activity that severely affected the communication routes and human settlements to a large extent.

After LandslideAfter LandslideAfter LandslideAfter Landslide

● We should Stay away from the slide area. There may be danger of additional slides.

● Check for injured and trapped persons near the slide area. Give first aid if trained.

● Remember to help your neighbors who may require special assistance--infants, elderly people, and people with disabilities.

● Listen to a radio or television for the latest emergency information.● We should Stay away from the slide area. There may be danger of

additional slides.● Check for damaged utility lines. Report any damage to the utility

company● Check the building foundation, chimney, and surrounding land for

damage● Replant damaged ground as soon as possible since erosion caused

by loss of ground cover can lead to flash flooding.

Landslide warningLandslide warning Landslide warningLandslide warning

● Sticking or jamming of doors or windows● Appearance of cracks in plaster, tile, brick, or foundations● Pulling away from the building of outside walls or stairs.● Slow development of widening cracks on the ground or on

paved areas such as streets.● Breakage of underground utility lines● Appearance of bulging ground at the base of a slope● Emergence of flowing ground water in new sites● Sudden decrease in creek water levels though rain is still

falling or just recently stopped● Tilting or moving of fences, retaining walls, utility poles, or

trees.● Faint rumbling sound that increases in volume as the landslide

nears. The ground slopes downward in one specific direction and may begin shifting in that direction under your feet.

Things to RememberThings to RememberThings to RememberThings to Remember

● Mudflows tend to flow in channels, but will often spread out over a floodplain. They generally occur in places where they have occurred before

● Landslides and mudflows usually strike without much appreciable warning. The force of rocks, soil, or other debris moving down a slope can devastate anything in its path. Take the following steps to be ready.

● Plant ground cover on slopes and build retaining walls.● In mudflow areas, build channels or deflection walls to

direct the flow around buildings

Remember: If we build walls to divert debris flow and the flow lands on a neighbor's property, you may be liable for damages

Precautions to be taken during landslidesPrecautions to be taken during landslidesPrecautions to be taken during landslidesPrecautions to be taken during landslides

If inside a building:-

● Stay inside● Take cover under a desk, table, or other piece of sturdy

furniture

If outdoors:-

● Try and get out of the path of the landslide or mudflow● Run to the nearest high ground in a direction away

from the path.● If rocks and other debris are approaching, run for the

nearest shelter such as a group of trees or a building● If escape is not possible, curl into a tight ball and

protect your head.

Incidents in IndiaIncidents in IndiaIncidents in IndiaIncidents in India

● Landslide incidence in Jammu & Kashmir – 18th April 2011 As per media reports five members of a family were killed and one injured in a landslide triggered by heavy rains in Doda District, Jammu & Kashmir.

● Landslide incidence in West Bengal – 26-27th March 2011 Two people were killed and an equal number were injured in a landslide in Evoke area of Cursing, Darjeeling District, West Bengal.

● Landslide incidence in Gujarat – 23rd March 2011 As per media report five persons were buried alive and two seriously injured in a landslide in Kharguli area of Gujarat.

● Landslide incidence in Hibachi Pradesh – 26th February – 5th March 2011 The incessant snowfall and rain in Kullu District resulted in landslides and blockage of Kullu-Manali road and Chandigarh- Manali highway. It also caused collapse of terraced fields and a four storey building and uprooting of apple trees; the foundation wall of Shiva Temple in Bran village was also damaged.

● Landslide incidence in Jammu & Kashmir – 14th February 2011 As per media report the Jammu-Srinagar National Highway was closed for traffic after flash floods and heavy rains triggered landslides in Ramban District and damaged the highway. It resulted in stranding of over 1200 vehicles.

● Landslide incidence – 11th January 2011 As per media report a landslide took place in Altinho hill when its side was being cut.  

Landslide Incidences Landslide Incidences

● Landslide incidence in Uttarakhand – 17th December 2010 In Uttarakhand a landslide halted operations at the Tehri Dam on River Bhagirathi. The landslide also struck the under-construction 400-MW Koteshwar Hydro Electric Project.

● Landslide incidence in Arunachal Pradesh – 22nd November 2010 The 330-year-old, Gaden Namgyal Lhatse Monastery in Tawang District, Arunachal Pradesh witnessed massive landslides. Some electric posts and plantation around the monastery were damaged.

● Landslide incidence in Karnataka- 08th November 2010 One person died as boulders crashed into two coaches of the Mangalore-Mumbai Matsyagandha Express near Karwar, district Uttar Kanara, Karnataka in the evening of 8th November 2010. In that incident one person got seriously injured and 14 more were hurt.

● Landslide incidence in Western Ghats – 27th October 2010 As per media a minor landslide caused cracks in the ground near Neyyar Dam at the foot of Western Ghats.One person died as boulders crashed into two coaches of the Mangalore-Mumbai Matsyagandha Express near Karwar, district Uttar Kanara, Karnataka in the evening of 8th November 2010. In that incident one person got seriously injured and 14 more were hurt.

● Landslide incidence in J&K- 23rd October 2010 An army captain, a Lance Naik and a Sepoy died in landslides, triggered in district Uri, J&K by heavy rains. These hampered traffic movement to Ladakh.

Landslide IncidencesLandslide Incidences Landslide IncidencesLandslide Incidences

● Landslide incidence in Assam-12th September Two persons were killed and about 300,000 displaced in flash floods and landslides triggered by heavy rains in the districts of Lakhimpur, Dhemaji, Golaghat and Bongaigaon of Assam.

● Landslide incidence in Uttarakhand - 8th September A student died after he got buried under the debris as a landslide hit the road while he was going to school at Kotagi area in Rudraprayag district.The 'Chardham Yatra' comprising pilgrimage to the four hilly shrines of Badrinath, Kedarnath, Yamunotri and Gangotri was halted as heavy rains triggered a series of landslides at a number of areas in Garhwal Himalayas.

● Landslide incidence in Andhra Pradesh- 1st September 2010 As many as 10 houses suffered damages and one municipal primary school was razed to ground following landslides on 1st September. Several incidents of boulders falling on the households on the hill slopes were reported.The landslides bulldozed at least four houses on the hill slope at Bramhanandareddy Nagar in Machavaram and three at Ghulam Mohiuddin Nagar and another three at Chittinagar area. The inmates escaped with minor injuries. A municipal primary school structure also collapsed in the incident.

● Landslide incidence in Mizoram - 6th August 2010 As per media report landslides on 6th August 2010 at Mamit town about 200km from Aizawl, in western Mizoram have damaged three houses. Ten houses and shops in the town’s market zone have been identified as “unsafe” and the residents have been directed to move to safer location.

ReferencesReferencesReferencesReferences

● Uttar Pradesh & Uttarakhand ● A Geotechnical Report on the Investigation of Ground Subsidence and Cracks in Farrukhabad Dist

rict, Uttar Pradesh

● A Note on the Development of Cracks in the Residential Building, Budaun Town, Uttar Pradesh ● A Report on the Landslides along Haripur-Koti Road at Ichari Dam, Dehradun District, Uttar Prade

sh, during August 1998

● A Report on Geotechnical Investigation of Lambagar Slide, Chamoli District, Uttar Pradesh ● A Report on the Study of the Bhagirathi Blockade between Dabrani and Loharinag in Uttarkashi D

istrict, Uttar Pradesh

● Himachal Pradesh ● A Note on the Subsidence Sink-Hole at Runjh, District, Mandi, Himachal Pradesh ● Progress Report No. 4 on Landslide Zonation in Mountainous Region of Himachal

Pradesh ● A Geological Note on the Investigation of Landslide nearSataun Bridge along Paonta-

Sataun Road, Dist. Sirmur, Himachal Pradesh ● A Note on the Reconnaissance of the Markunda Flood Protection Scheme, Sirmur

District, Himachal Pradesh ● Jammu & Kashmir ● Note on the Sinking Mada Village, Udhampur District, Jammu Province, Jammu and

Kashmir State. ● Geological Report on the Landslides along the Jammusrinagar National Highway (1a),

Jammu and Kashmir State. ● Inspection note on the Malori Slide on the Batote Bhadarwah Road, Jammu and

Kashmir State

● Geological Survey of India

ConclusionConclusion

●The Presentation is an example of cooperation between a Students to know about their professional society sharing common interests. Therefore ,we would once again like to thank Sr. Solly, our disaster management teacher for guiding in making his presentation a better one.

St. Mary`s School, Class ix ( group 4)