Monday, March 29, 2010

Revealing a hidden secret - landslides below Bong Bustee (village) and East Main Road (Kalimpong)




1. Much has been written and said about the Sindebung bustee (village) landslides which lie in the under-belly of Kalimpong, infact STH has regularly taken scientists, media people and students there and even produced a small video.
However, the landslides in lower Dungra and Bong bustees  (Map ‘A’) which lie below the most stable parts of Kalimpong ie (Bong Bustee and East Main Road area) have escaped such scrutiny and interest. The reasons maybe twofold :-

a) The area is inaccessible except to those who are prepared to slog it out on foot.
b) The people of the area, for some reason, have not spoken out.

2. On 27Mar2010, STH with the help of local volunteers trudged the area (Map ‘B’) on foot. The five hour trek revealed what was expected:-

a) The surface runoff rain water from the built up areas of town lying on the eastern face of the Kalimpong ridgeline (approx area circled in green - Map ‘A’) feed into a network of small tributaries which in turn empty into 4-5 major natural rivulets (or jhoras) which drain this area.

b) These major jhoras are causing intense scouring and loss of land to farmers in lower Bong and Dungra bustees.

c) Pasang jhora (Slide ‘1’) which emanates from the Baghdhara/ Mela ground area is a major cause of landslides in the Adhikari gaon and the people of the area have suffered major land loss here.

d) Gokulay jhora (Slide ‘2’) which originates from the Savitri Ghising road area in Bong Bustee is another major source of landslides in the area.

e) A smaller jhora called Naali Khola (Slide ‘3’) which originates from the SD hospital and then Gos Khan drains thru the Lower Dungra area and has caused some damage there. It is the source of a huge amount of pollution in this area since originates from a densely populated part of Kalimpong town.

f) The drainage from the Golf Course / East Main Road area has created huge landslide problems in the upper reaches - luckily in the lower areas, they pass thru areas with little or no population.


g) Villagers of the area said that almost the entire landslide problem was the result of the rains in 2009 and that prior to this period the jhora problem was not as acute.

3. As in the many other landslide zones visited the cause of landslides here is also wholly anthropogenic.
The pattern is now established and familiar – unplanned and rapidly expanding urban areas in the upper reaches causes a huge increase in the volumes of high velocity water flowing in the jhoras (natural drains) which are not designed to handle these volumes- this in turn causes erosion and landslides.


So if we humans are causing the landslides…it is upto us to try and prevent and mitigate them – and having seen the scale of devastation that is taking place in these mountains, I can predict that should we continue to neglect this issue as we are doing, much of our landscape will change not in a 100 years but in the next 15-20 years.


Praful Rao

Friday, March 26, 2010

STH Activities - 4 (How to prepare a 'Family Survival Kit' published in 'Himalaya Darpan')

Himalaya Darpan is the largest local daily with a circulation of over 40,000 in this region (a large part of which is affected by landslides).
They have agreed to allow STH to publish articles regularly regarding the landslide hazards ....the first one appeared today and it is about keeping a family survival kit handy in landslide prone areas so that people do not waste valuable time in an emergency and are able to survive on their own for 2-3 days until help arrives.

The article (in Nepali) is placed above.

My thanks to the Darpan team for giving space to highlight the most serious environmental challenge facing us who live in this region - landslides.

Praful Rao

Sunday, March 21, 2010

STH Investigation...NHPC Stage III Lo Dam at 27th Mile (20Mar2010)


At max magnification
on Google maps one could see lines resembling cracks at the ridge of a hill overlooking the National Hydroelectric Power Corporation (NHPC) Stage III Lo dam (Teesta River) at 27th Mile near Kalimpong , refer Slide 'A' (top).
STH organized a trip there on 20Mar2010 and walked the areas where the "crack" should have been with 2 local youths acting as guides ( see attachment 'B'jpg.).
We found no evidence of  "cracks/fissures" and the local village people whom we talked to verified this finding.

A possible explanation to the mysterious lines/cracks has been offered by Dr David Petley ,BSc (Hons) AKC PhD FRGS FGS ILTM CGeog (Wilson Chair in Hazard and Risk in the Department of Geography, Univ of Durham UK), whom I contacted yesterday. He writes:-

"Interpreting satellite imagery is notoriously difficult in situations like this, which is why we need either a good elevation model or (preferably) stereo coverage to do so properly. One particular problem is that when the sun angle is low (as per the Google Earth image), small features create shadows that make them look far more substantial. I suspect (though of course cannot say for certain) that this is the case in the images that you have looked at. I suspect that there is a small path or suchlike up there and the edges are casting shadows that look like cracks.I think if there really were cracks up there that one can see on Google Earth then they would have been very obvious on the ground."

That's the good news, the downside is that there are sinking areas below Deorali village (towards 28th Mile) and just above the dam site.

Praful Rao

Wednesday, March 17, 2010

SaveTheHills Activities (17Mar2010) ... (3)

As we continue our Community Based Disaster Risk Management (CBDRM) work in the rural sector (viz CHIBO- PASHYOR villages, our pilot project), today, we had a  meeting  with some young men and women at the village school.
We asked them to mark the vulnerable areas of their regions in printouts of  high resolution maps of the area which are now available. We will use their inputs to draw up a disaster management plan at the village level.

My thanks to Mr Yashwant Pradhan and Zion Lepcha of Chibo for organizing the many workshops in their area and also to Ranit Chatterjee, a young Disaster Management student from Tata Institute of Social Sciences (Mumbai) who has been doing his internship with STH for 3 weeks now - his contribution and work with us has been invaluable.

Praful Rao

Tuesday, March 16, 2010

High resolution images from Google


I am glad to inform you that Google has updated their images of this area recently as such one can obtain really good images and maps of the region (FREE!!!).
Placed on top is a satellite image of the CHIBO- PASHYOR landslides (Captions in Green are mine). The other photos show the same landslides from the ground.

Praful Rao

Saturday, March 13, 2010

SaveTheHills Activities (10Mar2010) ... (2)

I am extremely glad to state this is the second consecutive year that STH has been invited for the Seminar at NEPA. The occasion always gives me an opportunity to interact with other people working in the field of Disaster Management and see the many demonstrations that are put up by the National Disaster Response Force and in Mar2010, an excellent demo given by the civil defense department of Meghalaya state.

Praful Rao

Sunday, March 7, 2010

SaveTheHills Activities - (04/06Mar2010) .....(1)






Activity Log of STH for the past few days...

a) On 04Mar2010, we arranged a tour of the CHIBO/ PASHYOR landslides by Dr C Ghosh (NIDM) and Dr V Joshi (GB Pant Institute).
b) On 06Mar2010, we attended a Geo - Hazard Seminar at North Bengal University.

Praful Rao