Survey Report on Landslides: Sep2007

Report on survey of some landslide affected areas in the vicinity of Kalimpong by Kalimpong Consumer Association

Introduction

It is well known and documented that North Bengal and Sikkim lies in an area which receives some of the heaviest rainfall in the country. Also it is a fact that the area is weather sensitive being prone to sudden heavy to very heavy rainfall which can cause landslides. The monsoon season here lasts almost 6 months (April - Sept) and with the impact of global warming on climate change, the severity of the monsoons can only be expected to increase. Along with this is the factor that over the years this area has seen a drastic reduction in forest cover and an explosive increase in urban development which is largely unplanned.

Survey Report

Following almost a week of heavy and incessant rainfall in the first week of Sep2007, members of the Kalimpong Consumer Association made a survey of some landslide affected areas in the vicinity of Kalimpong town on 11Sep2007. A sketch of the affected areas in the immediate vicinity of Kalimpong town is attached as appendix “A”.

Observations of the team are as follows:-

a) Though the damage appears to have been mostly caused by the recent heavy and incessant rains in Jul and Sep2007, there is no doubt the erosion/landslide is the cumulative effect of rainfall over the years and also various other factors such as loss of forest cover, urbanization and lack of proper drainage.

b) The rains and other factors appear to have triggered off dormant landslides in new areas which were otherwise considered stable such as the 12^th mile and Gumba Hatta areas.

c) With the exception of some areas in the town , extensive havoc has been caused by rainfall in densely populated areas immediately adjacent to the main town area; these include

i) 11^th mile - a petrol pump has been destroyed at Topkhana. Several landslides have also taken place in this area and a 50’ section of the road to Algarah has sunk and is in imminent danger of collapsing.

ii) Gumba Hatta - A big crack has developed on HD Pradhan road in this area (which was till date stable.) The potential landslide here poses a direct and grave hazard in a very densely populated area.

iii) Tharpacholing monastery, Tirpai – a landslide near this monastery on DM Moktan road has blocked this road totally and threatens several buildings in this area.

iv) Hospital area - A huge crack has developed on KD Pradhan road just above doctor’s quarters and below the SDMO’s office. Any slip here will impact the residence of the doctors. There is also danger to the hospital (old surgical block) from the dhobi dhara area below.

v) Leprosy colony - A major landslide has taken place behind the colony kitchen. Further landslips or rock falls from this area poses a great danger to the village located below (Chota Bhalukhop).

vi) Chota Bhalukhop - Many landslips have taken place along the road between Munal Lodge and this area; two people died in a landslide at Chota Bhalukhop.

vii) Dhong dara - A crack has developed on the road leading from Tirpai to Dr Graham’s homes school (at Dhong dara) and some landslides have taken place in this area. It might be recollected that this area was always vulnerable and a large number of casualties occurred here I in the 1968 landslides; in the intervening years however, this area has been transformed into a densely populated area. Due to the imminent threat of landslides from Dhong dara, people of the area directly below ie next to the DD TV tower vacated their houses for almost a week and slept in the market place next to the Central School for Tibetans.

d) In the areas outside the town limits, the assessment made by the team was equally grim:-

i) Dr Graham’s Homes dispensary - There are several places where the road has sunk in this area (especially around ‘jhoras’- mountain streams) endangering not only those who are living in its proximity but also those who live below, in the path of the landslide.

ii) Sangsay Phatak - This is beyond the Hanuman statue at Dello. The entire hill has started sliding down and one can see huge cracks on the hillside, endangering not only an entire village above the road ie Dalapchand, Echay but also a huge area below. As on date this is the only motorable route from Kalimpong to the satellite towns of Algarah , Pedong and Lava and a breach on this road would maroon entire villages as well as close an alternate route to Siliguri from Kalimpong [since the lower route ie Rishi road has been closed for a week due to landslides at 14^th mile (see para v)]

iii) Dalapchand - The same type of situation exists here only perhaps a more dangerous one. The road is caving in at numerous places. Houses in these areas were evacuated for some time.

iv) Reshi road, 12^th mile -On this road, in the vicinity of Orchid Retreat, the road has caved in at least two 100 feet stretches and is in danger of collapsing.

v) 14^th mile - The survey team could not proceed towards Algarah beyond 14^th mile on Reshi Road because the road was closed due to landslides.

vi) Chibo – a “landslide prone area” which has suffered extensive damage in this period. The road to LK Pradhan nursery has been all but washed away, the Church and many other buildings are cracked and unsafe for human occupation.

vii) Sindebung - Another "landslide prone" area, like so many other places in Kalimpong. The only difference this time is the scale, some places here have sunk as much as 5' due to the rains of 2007 and villagers here quickly draw a parallel to what happened in1968. Perhaps the worst affected is the Gairi gaon area where the landslides and depressions pose a direct threat to 10th/11th/12mile area of Kalimpong.

viii) Teesta - Towards 27^thmile the situation is equally worrisome particularly in the vicinity of the NHPC Dam Stage IV at 27^th and 28mile where NH31 is reduced to small strips of kutcha road, much of the road having collapsed into the river below.

Findings

The survey team found that without sounding alarmist, there is a danger of a large scale catastrophe taking place in the areas visited if there is heavy precipitation on the scale that occurred in the first week of Sept2007 and this is entirely possible as the monsoons are still active in this region.

The team is also of the opinion that a similar situation exists in other parts of the subdivision (which were not surveyed) since the topography, soil structure and rainfall received is more or less the same.

Should no calamity take place this year, the same is entirely possible during heavy and incessant precipitation in the near future since with global warming the severity of weather is expected to increase sharply.

Recommendations

The team, though only comprising of concerned citizens and not experts in any related field urges concerned government agencies and NGO’s to give this document the highest priority in order to avoid large scale loss of life and property in the future. It also urges other bodies to independently verify the above findings in the whole of the subdivision since due to limitation of resources and time, the team could only survey a small portion of the subdivision and that too superficially.

It further recommends the following:-

a)A detailed study be carried out on the drainage pattern of rain water in the hills and a network of drains be planned and built in both urban and rural areas to channelize the huge amounts of storm water without damage to life and property.

b) Existing drains be broadened and maintained properly. All drains be cleaned at least once before the commencement of the monsoon period. It is also recommended that blockages of drains be cleared as soon as possible by local self help groups without waiting for government agencies/municipality to initiate action.

c)Jhoras are ultimately responsible in channelizing the entire water from the hills to rivers. Many of the sinking areas and much damage in the survey was observed adjacent to jhoras since most are in a state of disrepair. All jhoras may therefore be trained, strengthened and cleaned.

d) It is recommended that bamboo cultivation be avoided in landslide prone areas since it was evident that bamboo groves did not really bind the soil and had a counter productive role. Instead deep rooted trees which could hold soil be planted on active landslides and landslide prone areas.

e)Live disaster management exercises may be carried out by government agencies with the public both in rural and urban areas at least once a year to test the efficacy of the plan.

f) The Soil Conservation Dept was once very active in the past; working extensively in the catchment and sinking areas to conserve soil and prevent land slides. This maybe be taken up with renewed vigour.

g) The Social Forestry Dept must also be activated to educate people on the types of trees to be planted in landslide prone areas. Free saplings must be distributed in all such areas.

h) Many of the landslips were observed in the vicinity of recently constructed roads in rural areas; the fact that no drain had been constructed alongside the road and the walls of the newly excavated road were left without protection had made these new roads very susceptible to landslides. Suitable corrective measures maybe implemented.

j) Not withstanding the above, experts may be deputed from government agencies and NGOs to study the above issues and submit short and long term recommendations in order to avoid a catastrophe in the hills.

Conclusion

With the withdrawal of the monsoons and the onset of winters it is all too easy to forget the havoc and near disaster we have just experienced. Failure to act decisively and fast during the dry season (Oct-Apr) in all the affected areas however, may lead to a catastrophe on an unprecedented scale in the hills in the years to come.

praful rao