Discontinuity -fault Subterranean erosion Loading of slope/crest Permeability/ stiffness of material. Vegetation removal[fire/drought]

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Jody McCoy
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Note on Strengthening Early Warning System [landslides] Vijayawada Municipal Corporation & UNDP-DM Cell ======================================================== Introduction: Landslide defined as a

Landslides are ubiquitous and occur in all climates on most hilly terrains. Some rocks are more landslide resistant than others, but regolith is likely to be landslide prone.

On a rough estimate, nearly 15% of India s landmass, as many as 20 States of India are affected by different degrees of landslide hazards and landslides believed to account for up to 4% of total

1 Note on Strengthening Early Warning System [landslides] Vijayawada Municipal Corporation & UNDP-DM Cell ======================================================== Introduction: Landslide defined as a process involving downward and outward movement of a part of slope forming material along a definite plane i.e. plane of failure. It is caused due to shear failure along this plane. Landslides are ubiquitous and occur in all climates on most hilly terrains. Some rocks are more landslide resistant than others, but regolith is likely to be landslide prone. When landslides endanger humans and their installation, they are known as hazards; when they cause property damage and loss of life, they are disasters. On a rough estimate, nearly 15% of India s landmass, as many as 20 States of India are affected by different degrees of landslide hazards and landslides believed to account for up to 4% of total annual deaths. There is no early warning system for landslides in India, but Geological Survey of India is alerting the States periodically considering various factors [natural & anthropogenic] Vijayawada city is marked by undulating small and medium sized hillocks on northern, north-western & South-western with extensive plain lands between them. Although the hills here are a continuation of the Eastern Ghat chains, hills in general have a low elevation compared to the rest of the Ghats. Land/hill slides frequently occurring natural hazards in the hilly terrains in Vijayawada City, showing its impact during the monsoon period and when heavy rains from July to December. It has been many incidences of slippage rocks/stones reports in the City in the recent years, some time moderate earthquakes also cause triggering of landslides, particularly in regions marked by critically disposed and unstable slopes. Geological Survey of India categorize landslide into two categories, issues alerts and warnings to all designated authorities and agencies of the Central Government and State Governments/ district Administration for landslides. The State of Andhra Pradesh & Vijayawada City hill areas fall under Category II of GSI wherein moderate hill/slides occur frequently on the fringes of inhabited areas and result in limited loss of life and property. Main Causes of Land/hill slides: Geological causes Morphological causes Human causes Weak material Tectonic Excavation of slope Jointed or fissure Erosion by continuous run off Deforestation material over a slope Discontinuity -fault Subterranean erosion Loading of slope/crest Permeability/ stiffness of material Vegetation removal[fire/drought] Housing/construction without proper geological/engineering input Decomposition of rock Deposition loading slope Irrigation/farming practices Freeze-thaw weathering Mining Shrink-well weathering Water leakage

2 Types of Landslides: Slump Type of rock fall in which a downward and outward rotational movement of rock or soil occurs along a curved concave surface Rock fall Free falling of detached bodies bedrock[bounders]from a cliff of steep slope Rock slide Sudden down slope movement of detached masses of bedrock Debris fall Free falling is not only rock but overlying sediments and vegetation Creep Unnoticeably slow down slope movement of earth cover, utility poles fence Posts and gravestones etc appear titled or deformed on the surfaces Consequences of Landslides/hill slides: Direct & Indirect loses Loss of life death and injury Loss of property & assets houses, building, agriculture land & path Loss of infrastructure road, bridges, communication & electricity lines Loss of resources blocking river/stream, diverting water way/irrigation channel/tanks/reservoirs etc Loss of productivity land Reduced property value due to disaster prone area Investment cost high due to preventing and mitigation of future landslide Impact on emotional wellbeing Land/hill slide warning signs: 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. VMC Strategy for Disaster Mitigation for Landslide/s: Vijayawada being a big city in Andhra Pradesh, several people from all over Andhra Pradesh are migrating to Vijayawada for their livelihood irrespective of their caste, creed. The people who migrated to Vijayawada City started encroaching the by way of dwelling in the hill porambokes situated in Vijayawada Town. The encroachers have constructed pucca structures in many cases on the hilly areas, most of the people who encroach the hill porambokes and other Government porambokes in Vijayawada City are Artisans, Hawkers, small vendors and other daily wage coolies and eking their livelihood. The major hills are a]indrakiladri hill b]gollapalem gattu c]mogalrajapuram d] Machavaram e]gunadala, the height of hill ranges from 10mt to 250mt with covering 8.5 sq km covering 2 lakh population living. In Strengthening Early Warning System of Climate Risk Management Project of VMC-UNDP, the initiatives have been taken to roll out. It aims to strengthen and promote structural and non structural landslide mitigation efforts with Community

3 involvement/participation, further reducing the land slide /mud flow risk and vulnerability in the hilly pockets/habitations of Vijayawada Municipal Corporation. The following activities that are proposed in the wards / habitation around the hilly areas/divisions in the Vijayawada City focusing SHG women, Youth, Volunteers and NGOs ; Key activities proposed: Awareness/Media campaigns for sensitization[focusing women /Self Help Group/ members / youth/elders] Display Video/Audio display [short film/photo display] on impact of landslides/hill slides Knowledge Management; developing and distribution of leaflets exclusive on landslide impact in local language Kalazatha program cultural performance [Burakadha/Street play] Community organization [forming committee with Youth, Social workers & NGOs] Workshop/Meetings with key stakeholders of wards/divisions Establishment of Emergency Resource centre at central pocket on the fringes of foot hill area [to access information by community] Display boards/warning symbols at Vulnerable wards/divisions Early warning system establishment Hill slides/landslide vulnerable areas in City: Circle Area/location Division number Ramarajya nagar, Aggipette vari veedhi 33 Sitara theatre[church road] 29 Lambadipeta 30 1 Tailorpet 31 Katika Mastan Veehi 32 Potulaadiyya veedhi, Dokkara papaya veedhi 34 Mallikarjuna peta 25 Vijayanagar, Aurn nagar 3 3 Ramalaya veedhi, Venkataswamy veehi 6 Kasturiba peta, Khaja yelamanda Veedhi 19 In the process of Strengthening of Early Warning system in the City, 20 special cultural campaigns/special initiatives have been planned in the Vijayawada City hill areas. The two cultural agencies from Krishna District have been invited for performance of event in the most land/hill slide zones in the coming week after approval by Executive Authority, Vijayawada Municipal Corporation. Prepared by Sattar, UNDP CRM Project, VMC

Mass Wasting. Revisit: Erosion, Transportation, and Deposition

Mass Wasting. Revisit: Erosion, Transportation, and Deposition Mass Wasting Revisit: Erosion, Transportation, and Deposition While landslides are a normal part of erosion and surface processes, they can be very destructive to life and property! - Mass wasting: downslope