Malin Landslide: A Case Study

Mr. Shivaji M. SarvadeMr. Pratik S. Khadatare(Fabtech Technical Campus, College of Engineering & Research. Solapur, Maharashtra.)

One Day Workshop on Forensic Geotechnical Engineering, GNDEC, Ludhiana

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"Engineering is a noble sport . . . but occasional blundering is a

part of the game. Let it be your ambition to be the first one to

discover and announce your blunders. . . . Once you begin to feel

tempted to deny your blunders in the face of reasonable evidence

you have ceased to be a good sport. You are already a crank or a

grouch.”

~ Karl Terzaghi

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Introduction

• A massive landslide wiped out the village of Malin located at 110

KM from Pune city, in the Western Ghats on July 30.

• Mound of mud and debris that came down from a nearby hillock,

swallowed up almost the entire tribal village of around 50 families.

• Final death toll was 153 when the rescue operation was stopped

and around 100 people were missing

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Introduction

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GEOGRAPHICAL BACKGROUND • Malin village is a part of western ghat which is a UNESCO World

Heritage Site and is one of the eight "hottest hotspots" of biological diversity in the world with average rainfall of 1171 mm.

• Basalt is the predominant rock found in the hills reaching a thickness of 3 km. Other rock types found are granite gneiss, metamorphic gneisses etc. with detached occurrences of crystalline limestone, iron ore, dolerites and anorthosites.

• Malin is southern part of Ambegaon taluka which falls to the foothill of Sahyadri Mountain range and is towards the west side of Pune city.

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CULPRITS…

• Very Heavy Rainfall.

• Deforestation and Levelling Of Land on the Hill for Cultivation.

• Change in Agriculture Practice

• Backwater of Dimbhe Dam.

• Human Interference in Nature.

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CULPRITS…

TRMM time series precipitation graph for the Malin in the last week of July

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CULPRITS…

• Very Heavy Rainfall.

• Deforestation and Levelling of Land on the Hill for Cultivation.

• Change in Agriculture Practice

• Backwater of Dimbhe Dam.

• Human Interference in Nature.

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CULPRITS…

• Very Heavy Rainfall.

• Deforestation and Levelling Of Land on the Hill for Cultivation.

• Change in Agriculture Practice

• Backwater of Dimbhe Dam.

• Human Interference in Nature.

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CULPRITS…

• Very Heavy Rainfall.

• Deforestation and Levelling Of Land on the Hill for Cultivation.

• Change in Agriculture Practice

• Backwater of Dimbhe Dam.

• Human Interference in Nature.

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CULPRITS…

Backwater of Dimbhe Dam.

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CULPRITS…

• Very Heavy Rainfall.

• Deforestation and Levelling Of Land on the Hill for Cultivation.

• Change in Agriculture Practice

• Backwater of Dimbhe Dam.

• Human Interference in Nature.

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MITIGATION • Land Assessment.

• Slope Stabilization and Development.

• Prepare Slope Stability Maps.

• Prepare Landslide Inventory Database.

• Redirect Debris Channel.

• Vegetation.

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MITIGATION • Land Assessment.

• Slope Stabilization and Development.

• Prepare Slope Stability Maps.

• Prepare Landslide Inventory Database.

• Redirect Debris Channel.

• Vegetation.

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MITIGATION

Slope Stability

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MITIGATION • Land Assessment.

• Slope Stabilization and Development.

• Prepare Slope Stability Maps.

• Prepare Landslide Inventory Database.

• Redirect Debris Channel.

• Vegetation.

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MITIGATION • Land Assessment.

• Slope Stabilization and Development.

• Prepare Slope Stability Maps.

• Prepare Landslide Inventory Database.

• Redirect Debris Channel.

• Vegetation.

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MITIGATION • Land Assessment.

• Slope Stabilization and Development.

• Prepare Slope Stability Maps.

• Prepare Landslide Inventory Database.

• Redirect Debris Channel.

• Vegetation.

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MITIGATION

Redirect Debris Channel

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MITIGATION • Land Assessment.

• Slope Stabilization and Development.

• Prepare Slope Stability Maps.

• Prepare Landslide Inventory Database.

• Redirect Debris Channel.

• Vegetation.

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MITIGATION

Vegetation on slopes

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PRECAUTIONARY MEASURES• The natural drainage shouldn’t be disturbed or blocked on the

slope.

• For support wall, wider base and slightly incline (towards hill) are to be provided.

• Care should be taken for anything that may move/fall downward.

• Exposing a very high vertical face should be avoided.

• Avoid adding load very close to the edge of the slope.

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ALERT SYSTEMS

• Efforts shall be taken to devise a program which can generate

alerts for prospective landslides in the potential zones.

• One such system is NASA-TRMM (Tropical Rainfall Measuring

Mission).

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ALERT SYSTEMS

TRMM data for the Malin landslide, sourced 30th July

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Concluding Remarks. • Landslides are common in the area during the monsoon season,

which runs from June through September.

• Similar deforestation and environmental damage have caused floods and landslides in other parts of India.

• Last year, more than 6,000 people were killed as floods and landslides swept through Uttarakhand state during the monsoon season.

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Concluding Remarks. • According to the information obtained under RTI, In Mumbai city over

22,483 hutment in 327 hilly areas across 25 Assembly constituencies

in the city, including Western and Eastern suburbs, are dangerous and

the people living there need to be shifted as soon as possible.

• In the main city, 49 spots are dangerous in which total hutments are

3986, while in Mumbai Suburb 278 spots are most dangerous.

THANK YOU.