Extreme rainfall event in the Darjeeling district: 04/05Oct2025 (Part IIIB - damage caused by 'non- fatal landslides')

 Non - fatal landslides

The intense storm of 04–05 October 2025 triggered numerous non-fatal, rain-induced landslides of varying types and magnitudes across the Darjeeling–Kalimpong region (see above). Official estimates place the number of landslides in Darjeeling district alone at nearly 500. Given the scale of the event and the difficulty of surveying each site, this report focuses on a selection of the major landslides.

Seeyok Tea Garden - Sukhia block.

a. Area involved: Goddam dhura Ward 10 consists of 336 people in 87 homes.

b. Circumstances: Heavy rainfall began across the region on the evening of 04 October 2025. As the intensity increased, several residents—most of them tea garden workers—woke their neighbours and urged them to move to safer ground. One woman, an ASHA worker who had received RED alerts on her mobile phone, also went door-to-door warning others of the danger. Around 2 a.m. on 05 October 2025, a massive landslide struck, accompanied by a deafening roar reminiscent of an explosion. The Rangli River, normally a small stream, had swollen into a torrent, altered its course, and swept away two bridges in the area.
c. Damage: 7 homes completely damaged, 3 partially damaged. Livestock has been lost and vegetable gardens are ruined. Roads in the area are in a mess. 32 people were living in a relief camp. Many vehicles and two wheelers belonging to the community were washed away.

Goddam Dhura after the deluge of 05Oct2025. It is amazing that even after such devastation,
no one died - in large part due to the alertness of the community and timely evacuation to safer ground.

The tea industry, both in the Dooars and the hills, suffered huge losses because of the heavy rains. Here you see large landslides ruining parts of a garden - Goddam Dhura is visible in the valley below.

Drone image of Goddam Dhura on 17Oct2025. The rampage and destruction by the river is very apparent.

Taba Koshi, Mirik Subdivision (Coords 26.921391N 88.173500E)

a. Area: Taba Koshi is a series of around 40 homestays along the Rangbangh river which came up during the time of Subash Ghisingh and which started flourishing once road communication links from the area to Siliguri, Mirik and so on were established.
On 04Oct2025, due to the festive season, almost all the homestays were full with tourists from the plains.
b. Circumstances: As in other areas, rainfall started during the day on 04Oct2025 but intensified after 6pm and became really heavy later. Noticing the Rangbangh river had started crossed all danger levels, the locals started evacuating their guests to safer places after midnight. The power supply which had been erratic, thru the day because of the intense lightning on 04Oct2025 went OFF altogether at night so everything had to be done in pitch darkness and in heavy rain. So it was nothing short of a miracle that no one died.

c. Damages/loss: Many of the homestays were damaged as the Rangbangh river surged into the compounds and swept away vehicles as well as parts of the homestays in the early hours of 05Oct2025. There was significant damage to roads as well as to power lines and poles.

Damage to homes and infrastructure at Taba Koshi by the Rangbangh river - photo taken on 17Oct2025 more than two weeks after the deluge.

The Rangbangh river seen here is by all accounts a tiny stream which on the 05Oct2025 became a roaring torrent after the heavy rainfall on 04/05Oct2025. The river changed its course and threatened many homestays which were otherwise quite far from the river. Here, an earthmoving equipment is being used to correct the river's path.

The rampaging Rangbangh river caused extensive damage to roads and bridges at Taba Koshi on 04/05Oct2025.

A vehicle drives over a temporary bridge made of hewn pipes because of damage to the original bridge by the river on 05Oct2025

A smashed vehicle lying on the banks of Rangbangh river. Many such vehicles were lost because the homestay owners never believed the river, otherwise a tiny stream was capable of such devastation.

Massively eroded part of a homestay at Taba Koshi.

Damaged parts of a homestay and power lines at Taba Koshi, Mirik.

On 05Oct2025, a tiny stream (Rangbangh river) transformed into a rampaging torrent and brought down these massive boulders to a homestay at Taba Koshi.

This is the heart of tea country in Darjeeling district and the havoc wreaked by the rain and ensuing landslides is huge. Large parts of tea gardens have been severely mauled by the disaster o 04/05Oct2025.

Report by STH Survey team (which will be updated as and when possible)

From Left to Right
Steve Rai(interviews and videos with Praveen)
Yukta Acharya (Interviews and records): yuktaa1999@gmail.com
Shreya Gurung (Interviews): shreyagurung07@gmail.com
Praveen Chhetri (all drone images and photographs): junkeristudio@gmail.com

with sincere thanks and appreciation to Roshan, Rajen bhai and Priya of Darjeeling Himalaya Initiative (DHI)
and also to Aachal (Anugyalaya DDSSS) for helping with resource persons and information.

Praful Rao
savethehills@gmail.com
9475033744

Impact of the Oct 2023 Teesta Valley GLOF: Photosurvey of the Geil khola - Likhu bhir section of NH10 on 23Aug2024

NH10 winds itself along the banks of the Teesta river. Gangtok and Kalimpong are towards the right hand side whereas Siliguri is towards the left.

The monsoons have been playing truant in our region recently. Broadly speaking, after the heavy rains in Jun2024, going into mid July, we had less rain towards the latter part of July2024 and deficient rains in August2024.
The deficient rainfall is worrisome in terms of water availability in our region but has allowed the NH10 repairs to progress and yesterday (23Aug2024) the highway was declared open once more:

I photographed the Geil Khola - Likhu Bhir section on 23Aug2024 and have placed several large images of this area which has been one of the most troublesome part of NH10 for maintenance after the Oct 2023 Teesta Valley GLOF in the hope that it may benefit  researchers, engineers and especially lay people who use the highway. You might even like to compare these recent images with our report of the same area done on 18Oct2023.

With the river flowing 4-5m above pre-GLOF levels, it is now running close to the level of the road (and also closer to the IRCON tunnel as well), increasing erosion of the road and the maintenance problems. Teesta bridge is in the top right hand corner.

This image clearly shows how close the river is to Teesta bazar (top right hand corner) of which several areas are sinking and the level of the river between Rabi jhora (see map) and the Teesta bridge thru which the Darjeeling- Kalimpong is routed.

Notice the level of the Teesta as it hugs the NH10 in between Geil Khola (extreme right) and the settlement (29Mile or Baluatar) at the center of the photo.

Section of NH10 between Baluatar (settlement on the right hand side) and Teesta Low Dam Project III (TLDPIII), left top.

The Likhu Bhir section of the NH10 - perhaps the most troublesome part for maintenance as well as traffic jams.

Geil khola - Likhu Bhir - Teesta Bridge (top right) section. The post -GLOF Teesta river is flowing bank to bank even with deficient rainfall in Darjeeling -Sikkim Himalaya over the past two weeks. We still have a month or more of rains left.

Documentation of the above report supported by Royal Enfield, as part of its Social Mission Initiative

Praful Rao
SaveTheHills,
Darjeeling-Sikkim Himalaya
savethehills@gmail.com
9475033744

Impact of the Oct 2023 Teesta Valley GLOF on road communications at Likhu Bhir on NH10 ( Kalimpong district, 13-14Apr2024)

On what is becoming a familiar story, NH10 is closed for maintenance work and again at Likhu Bhir - an old landslide, who's ghosts were resurrected by the GLOF of 04Oct2023 and is causing headaches to the District Admin & PWD and nightmares to those using the highway. It is closed again this weekend, seven days after it was shut down for repair last week.

Images of maintenance work taking place on NH10 at Likhu Bhir on 13Apr2024

My thanks to Mr Mukesh Sharma, reporter from Kalimpong for sharing these images with STH


Praful Rao
Kalimpong district
Darjeeling Sikkim Himalaya
savethehills@gmail.com
9475033744

The National Highway 10 (NH10 - Siliguri to Gangtok) maintenance problem (post GLOF) begins in Mar2024

NH10 and Likhu Bhir in 2017 & 2023

MoRTH website on NH10 reads as follows:
'The highway starting from Indo / Bangladesh Border connecting Fulbari Siliguri in the State of West Bengal connecting Sivok, Kalimpang near N.H-10 and terminating at Gangtok in the State of Sikkim'. 52kms of the highway is in Sikkim, the remaining 65.97kms being in W Bengal.
Further to our earlier report on National Highway 10 (NH10), the recent rains in our region caused landslides along parts of NH10 which resulted in road blockages and traffic jams and as such the Kalimpong District Administration has closed parts of NH10 for traffic as per the letter below:

 

 

Prolonged closure of NH10 dates
Road closures for several hours on NH10 due to landslips, erosion and rockfalls etc are commonplace and take place almost daily during the monsoons. Prolonged closure dates of the highway in the recent past are as follows:-
* In 2007 and 11Jun2010 at HaatiSurey, near Coronation bridge – blocked for a week.
* 26Jun-03Jul2015 due to landslide at SetiJhora (near TLDP IV)
* 14-15Jan 2016 due to landslide at BhoteyBhir (near Rangpo)
* 06Jul2019 for almost a week at Seti Jhora

Despite several alternate routes now being available (see map below), NH10 remains the shortest distance with the least gradient changes and is the quickest way to commute from Sikkim and Kalimpong to SIliguri and the plains of North Bengal - however, it may not be the safest route anymore.

NH10 and alternate routes

DATA ON NH10 (and the alternate routes from Gangtok and Kalimpong to Siliguri)

Distances - Siliguri to Gangtok
Via NH10 - 114kms out of which approx 90kms is in mountainous terrain. Approx 60kms from Singtam to Sevoke is along the banks of the Teesta river.
a. Alternate route 1 (via Pakyong- Reshi-Algarah-Lava-Sevoke-Siliguri) - 241kms
b. Alternate route 2 (via Rangpo-Chitrey-Kalimpong-Algarah-Lava-Sevoke-Siliguri)  - 205kms

Distances- Kalimpong to Siliguri  
Via NH10 - 67kms
a. Alternate route 1 (via Ghoom -Kurseong) - 99kms
b. Alternate route 2 (via Algarah-Lava- Gorubathan-Sevoke) - 132kms
c. Alternate route 3 (across Relli river- Samthar- Panbu-Kalijhora-Sevoke)

It is estimated that approximately 3000 vehicles use the NH10 daily when permitted.

Images of landslide and traffic snarls in that part of the road

Rockfall at Likhu Bhir after rains on 23Mar2024

Traffic jam at Chitrey (Teesta) due to rock fall at Likhu Bhir, 23Nov2024

Traffic jam at Likhu Bhir on 24Jan2024 at around 6pm

 

As we have reported earlier, Likhu Bhir is an old landslide which was dormant for many years until the GLOF of 04Oct2023 reactivated it.

File photo from July2019

Also as reported, the Teesta river bed has risen by almost 4m all along the valley due to the silt and sand deposits brought down by the GLOF, which makes NH10 much more prone to subsidence/erosion (the TLDP III and IV dam activities and the IRCON tunnelling having contributed their share to making sections of NH10 more prone to subsidence, rockfalls and landslides)

Rainfall (at Kalimpong) from 19Mar to 23Mar2024
107mm.
It was surprising that very moderate rainfall, after almost 4 months of complete drought could trigger so much instability in the Likhu Bhir area.
Recently, I met a geomorphologist who said that the Oct 2023 Teesta Valley GLOF was the biggest such event in the Himalayas in the recent past. I believe him entirely.

My thanks to our WhatsApp group 'HA' members who's photos I have used :)

Praful Rao
Kalimpong district
Darjeeling-Sikkim Himalaya
savethehills@gmail.com
9475033744

Photographic record (18Oct2023) of Geil khola section of NH10 - post Lhonak Glacier GLOF.

One of the main casualties of the devastating Lhonak glacier GLOF on 04Oct2023 was the road communications and that too mainly the impact of the floods on NH10 which is the lifeline for the landlocked, mountain state of Sikkim and of Kalimpong district in W Bengal. Of the approx 114km distance from Siliguri to Gangtok, 65kms of NH10 winds itself along the banks of the Teesta.
More than two weeks after the GLOF of 04Oct2023 which shredded the highway at many places the road communications from Gangtok to Siliguri along NH10 has not been restored till date - neither the state highway which connects Darjeeling to Teesta Bazaar.

On 18Oct2023, I photographed the above section of NH10 from the sheer cliffs of Kalimpong district which overlook the highway from the opposite hill - with the intention of preserving the images of what was an extraordinary event for us living in this region.

The above image of Oct 2021 shows a very active landslide (A) at 29th Mile on NH10 (27 01.013N 088 26.087E) and Bangay bazar (B) on the banks of the Teesta.

Telephoto Image of NHPC's TLDPIII and parts of Bangay bazar on 18Oct2023, submerged by the GLOF. Dam operations on TLDPIII has been stopped by the local political party (GTA) for the time being. Do notice the width of the Teesta river and the color of its water which indicates it is still loaded with silt.

                                       A very active 29the Mile landslide zone in 2021.

This year the 29th Mile landslide remained stable even during the GLOF period.

Close up view of the same area on 18Oct2023. The huge mounds of sand on the right bank indicate river levels during the GLOF. NH10 also appears to have been eroded at places.

Likhu Bhir (27 02.181N 088 25.661E) was the most serious landslide on this route decades ago (see image below). After being relatively stable for years, it was reactivated by the GLOF. One can see trucks carrying construction material plying over the slide.

Geil khola (27.028965N 088.427644E) was one of the places which was hit by the GLOF of 04Oct2023. Notice the partly buried homes on the river bank. The District Administration has set up a relief camp at Geil Khola.

Geil khola and its surroundings on 18Oct2023.

Geil Khola - Likhu bhir section of NH10 on 18Oct2023.

It seems ironic that the Kalimpong element of Darjeeling Himalaya Railways (DHR) which used to operate the narrow gauge train from Siliguri to Geil Khola, discontinued its Kalimpong operations after the 1950 disaster in our region.

Damage to DHR tracks in Darjeeling by the June 1950 disaster (photo kind courtesy Das Studio, Darjeeling)

File photo of the Geil Khola - Teesta Bazaar section of NH10 in May 2017.

The same section of the road after the GLOF - notice the level and size of the Teesta river and the many places eroded on NH10.

This place is in the vicinity of the Teesta bridge. The erosion of the road along the banks of the Teesta can be seen here.
Will the NHPC TLDP III dam operations under circumstances where the level of the river has now risen significantly affect NH10?
Also the safety of the thousands of vehicles which will ply on the highway when it is reopens and especially during the monsoons of 2024 are questions which need to be pondered upon.

Praful Rao
Kalimpong district
Darjeeling Sikkim Himalaya
savethehills@gmail.com
9475033744