Reduce climate changeinduced risks and vulnerabilities from GLOF in the Punakha Wangdue and Chamkhar

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Reduce climate change-induced risks and
vulnerabilities from GLOF in the Punakha- Wangdue
and Chamkhar Valley,
By Deo Raj Gurung Geomorphologist
Department of Geology Mines, Ministry of Trade
Industry January 24, 2007
Department of Geology and Mines Ministry of Trade
and Industry, Thimphu
UNDPGEF
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• Topics
• Global warming
• glaciers response
• Update on DGMs
• activities
• Recommendations from
• earlier works
• Future plan
• Present project
• Dissemination

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Glaciers Global Warming
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Relationship between climate and glacier
response (modified from Meier,1965)
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Global Warming and Glaciers in the Himalayas

• Nepal Himalaya
• - Retreat rates from 3 m to 66 m
• (Yamada et al 92,Kadota et al 00, Samjawal, 05)
• Chinese Himalaya
• - 5.5 shrinkage in last 24 years (CAS)
• - 45m 68m retreat-Xixiabangma mts (Mool,05)
• Indian Himalaya
• - 4m to 23 m retreat rate (Various authors)

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How is the picture in Bhutan Himalaya?

• 30 - 35 m retreat rate for large glaciers
  associated with lakes (Ageta et al, 2001)
• Shrinkage (area) of glaciers in Bhutan 10.7
• Rate of enlargement (surface area) of lakes
  3.28

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Karma et al. (2003)

• More rapid glacier retreat in Bhutan than in Nepal

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Other aspects of climate change

• Signs from Nepal
• (Manang Mustang)
• Erratic pattern
• Intensity of Rainfall
• Declining of
• Himalayan grass land
• Problems related
• to Mosquitoes at
• 2700m
• Shift in the Agriculture
• practice

Rice harvest in Bumthang ( 2800m)
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Update on DGMs activity 1. Lunana Complex

• 1986 Joint DGM-GSI
• Lunana Expedition.
• 1994 DGM was part of
• multidisciplinary to assess
• the situation after the
• GLOF.
• 1995 Expedition to Lunana by Indo-Bhutanese
  team to
• identify the cause of 1994 GLOF.
• 1996 Expedition to Roduphu glacial lake by
  multidisciplinary
• team (NEC, DGM, DoR, Bhutan Survey)
• 1996 1998 Mitigation exercise for Raphstreng
  Tsho in
• collaboration with GOI, under
  coordination of MoHCA.

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Schematic sketch of excavation work carried out
for the mitigation of Raphstreng Tsho in 1996
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• 1998- Joint Bhutan
• Japan Project for risk
• assessment of GLOF.
• 1999-2001- Joint
• Bhutan-Austria Project
• for risk assessment
• of glaciers and glacial
• lakes.
• 2002-2004 Regular monitoring of glaciers and
  glacial lakes
• by DGM
• 2005-2006 - Detailed topographic survey by DGM.

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Detailed topographic map of Lunana complex
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2. Activities in headwater of Chamkhar Chu

• 1999 Expedition to head water of Chamkhar Chu
  (Upe Tsho
• Chubda Tsho).
• 2002 Joint Bhutan-Japan expedition to Chubda
  Tsho to assess
• the risk of GLOF.
• 2004 Expedition to Chubda Tsho to assess the
  risk of GLOF.

Click here for time series expansion of Tsobda
Tsho
Next
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Back
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Inventory works on glaciers and glacial lakes
for the entire country
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Summary of works on inventory of glaciers and
glacial lakes DGM-
ICIMOD
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Potentially dangerous glacial lakes in Bhutan
Pho Chu Sub Basin 9 Mo Chu Sub Basin
5 Chamkhar Chu Sub Basin 3 Kuri Chu Sub Basin
1 Mangde Chu Sub Basin 7
Out of 2794 glacial lakes, 25 has been identified
as potentially dangerous lakes.
Source DGM ICIMOD publication
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Recommendation from earlier works

• Construction of control
• structure at the outlet of
• Luggye Tsho.
• Controlled breaching
• of Thorthormi Tsho
• manaully to lower water
• level by 5m.
• Hazard zonation mapping for GLOF along
  downstream.
• Installation of early warning system (EWS)
• Regular monitoring

Details
Next
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Brauner et al, 2003 - Manually controlled
breaching of Thorthormi lake to reduce
water level by 5m.
Project duration 4 working months for 4
years. Project cost 2.3 million Euro (Approx.)
Back
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Follow up action

• Hazard mapping along
• Puna-Tsang Chu basin
• (DGM-Austria project,
• DGM-NCAP project).
• Hazard mapping along
• Chamkhar basin
• (Present project).
• Early Warning System (EWS) 2 staffs of Flood
  Warning
• Section (FWS) under Department of Energy (DoE)
• presently stationed in Lunana with wireless
  facility.
• Continuing monitoring exercise.
• Mobilizing funds for manually lowering of
  Thorthormi level.

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DGM Camp, 2005
Future Plan

• Continue regular
• monitoring
• Monitor other basins
• (Pa Chu, Mangde Chu)
• Manual widening of
• Thorthormi outlet
• Update glaciers and glacial lakes inventory
  regularly.
• Installation of TEWS in Chamkhar Chu

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Tsobda Tsho, 2004

• Detailed survey (topographical bathymetric)
• of Tsobda Tsho.
• Dissemination of information to planners and
• policy personnel.

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Reduce climate change-induced risks and
vulnerabilities from GLOF in the Punakha-
Wangdue and Chamkhar Valley.
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Course of action - Nutshell
What ??
How ??
Collection of Existing Data from Different
Organization
Desktop Study (Office)
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Input Phase
Work Flow stages

• Field Work
• Remotely Sense data
• Existing data and
• reports

Data Acquisition
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Using RS/GIS tool
Assessment of suitable EWS and Location
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Outcome Phase
Data Processing, Analysis, and creation Database
Final Report and Dissemination
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In put data

• Field Data
• Geomorphologic
• Geological
• Material
• Slope
• River course Data
• Land use Type
• Socio economic survey
• Landslide inventory
• Past Historic on GLOF
• Property Survey
• River cross section
• Infrastructure/built up

• Data on Desk
• Topographical Map
• 150,000
• Aerial Photos
• Quickbird Imagery
• DEM, 15x15m
• GLOF Inventory 2001
• GIS Data from DOE
• GIS data from MOA
• National Parks data
• Road network data
• Schools and Institution
• Hydrology and
• Metreological data

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Punakha-Wangdue Component
QuickBird Image (Dec, 2005)

• Most studied basin
• in regard to GLOF
• Hazard mapping
• done upto Khur-
• uthang by DGM-
• Austrian Team
• Hazard zonation
• mapping below
• Khuruthang is in
• progress (NCAP
• Funded)
• Feasibility study for installation of TEWS.

We are here!
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TEWS Feasibility study

• Identification of
• appropriate TEW
• System (Study tour).
• Identification of site
• for installation of
• TEWS using Spatial
• Analysis in GIS
• platform.
• Field visit for verification.

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Source
Water level
Sensor
Pressure change
Manually
Ground vibration
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Chamkhar component
Hazard zonation mapping Between Khakthang to
confluence between Chamkhar Chumme Chu
Kurjey Lakhang
Jakar Dzong
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View (north-south) of Study Area
Chamkhar
Sapchithang
Naspe
Khakthang
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Project objective

• To produce high quality
• hazard map of Cham-
• khar Chu basin betwe-
• en Khakthang and
• confluence between
• Chamkhar Chu and
• Chumme Chu.
• Disseminating of
• information thus generated to grass root level.
  
• Generate baseline database using Geographical
  Information
• System (GIS).

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Source data a major constrain for hazard
zonation mapping.
Handicapped
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(No Transcript)
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• Flood hydrographs is
• vital for flood hazard
• zonation

Dam Breach model

• Lake volume
• surface area
• Topographic data
• Geo-technical
• parameters of
• moraine.

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Alternative 1 (Back Calculation)

• There are five tiers of fluvial terraces in
  Chamkhar
• valley (Gurung, 2002).

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Alternative 2 (Subjective analysis)
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Hazard zonation map of Punakha (Punakha Dzong to
Khuruthang) -
Austro-Bhutan Project
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Output

• Chamkhar Component
• Technical Reports and
• Hazard Zonation Map
• GIS Database

• Puna-Tsang Chu component
• Feasibility report on assessm-
• ent of EWS and finding suitable
• location

Dissemination (through series of workshops)
National level workshop (stack holders)
Department of Local Government
Dzongkhag level workshops
Geog level workshops
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Thank you very much for you attention
Team Members
Mr. Yeshi Dorji, Project Director
Mr. Tika Thapa, Field Geologist
Mr. Dowchu Drukpa, Project Manager
Mr. Lalit Chhetri, GIS Specialist