Caught amidst a flash flood in Bahrabise

Mandira Singh Shrestha
Pradeep Man Dangol
Gushing flood waters of the Sun Koshi at the Jure landslide area
Photo: Pradeep Man Dangol

By the mid-monsoon, flash floods of Bhote Koshi had already swept away more than 65 houses and placed 200 more at risk. With rains becoming heavier, further damage was expected. Searching for a better understanding of the increasing risks along the Bhote Koshi river, a team of four from the International Centre for Integrated Mountain Development (ICIMOD) went to Bahrabise searching for firsthand accounts of the transbounary floods that originated in the Tibetan autonomous region of China. 

The trail of destruction of the Bhote Koshi floods was visible from the Khadichaur area. Though there were no reported human causalities we found the flash floods had created havoc and fear in peoples mind. The community was well connected — everyone had been warned by mobile phone or word of mouth to move to higher ground. 

‘I ran uphill clutching my granddaughter’, said 57-year-old Puta Maya. According to Ms Maya, she had not been able to rebuild her house that was destroyed by the earthquake and now faced the risk of flooding. Ironically, locals seemed happy with the fish they captured immediately after the floods which sold for around Rs 400/- per kg.

Upstream of Lamosanghu at the Sun Koshi barrage, all four gates of the intake were closed before the floods arrived to the intake site preventing damage to the canals and the turbines. 

‘Due to timely warning from multiple sources including the head office, friends at Khasa and Bahrabise, we could fully open the sluice gates and close the intakes that protected the bypass and main canal’, said Rajesh Thapa, operator with the Nepal Electricity Authority. Huge boulders and sediments brought down by the floods were deposited on the right bank completely closed down power production of the 10 MW Sunkoshi HEP.

Sand casted flood plains of the SunKoshi
Photo: Pradeep Man Dangol

At Jure we could still see the remnants of the houses that were destroyed by the massive landslide in August 2014. The temporary road seemed to have further been eroded with visible signs of toe undercutting. The landslide landscape in the background looked beautiful with some greenery and a few waterfalls. We looked for the scenic lake that was formed by the landslide our during last visit in 2015. As the road turned, we were shocked to see a sand casted flood plain with the Sun Koshi river diverted toward the left bank. Out of the many houses underwater, only one was visible with the remaining completely buried under the fine sediments. The floods had completely changed the landscape. Instead of standing water, large deposits of silt and sand on the floodplains gave it a deserted look leaving the Sun Koshi river a narrow opening through which to flow.

Just a few kilometers upstream of Jure, we stopped to chat with a few of the local shopkeepers along a row of small shops on the road leading to Bahrabise. Krishna Maya Tamang of Kolbari Tole, Ramche 7 said they were living in a multi-hazard environment with floods, landslides and earthquake. 

Consultation with the local community near Bahrabise
Photo: Ujol Serchan

‘Often, when it is raining we spend sleepless nights taking turns to watch the river. In 2014, there was a massive landslide in Jure, in 2015 the Gorkha earthquake, and now in 2016 the flash floods that came down the Bhote Koshi’, she said. When Krishna Maya heard about the floods coming from the Tibetan border, she and her family and friends fled up hill for safety despite the fear of landslides. They came back down after a few hours when the flows had receded somewhat. Besides Krishna Maya, there were hundreds of such people living above the banks that have been their homes for years. 

The once bustling Bahrabise town looked deserted. The shops on either side of the road had fewer items displayed, indicating the loss of trade due to the closure of the route to Tatopani. Fewer women, men and children were on the streets occupied with their normal chores.

Water level monitoring of the Sun Koshi at bahrabise
Photo: Pradeep Man Dangol

The bridge across the Bhote Koshi was lucky to be still standing after the powerful flood eroded the left embankment of the bridge. The road department dumped several truckloads of boulders on the embankment and abutment to protect it from further erosion and to ensure Bahrabise town remained linked with Kathmandu. Real-time monitoring of the water level is essential to provide warning to the downstream. The Department of Hydrology and Meteorology had installed a new radar sensor to monitor the water level at the bridge as an earlier water level sensor was damaged by the flood. We talked with several local people about the flood and the preparedness measures in place. They seemed to be more worried about the disruption in the road connectivity than the risk of floods. 

As we finished our lunch the clouds became darker. A few drops of rain started as we made our way back toward Kathmandu. As we approached the Jure landslide area about the 3 km from the Bahrabise town, the intensity of the rainfall increased. The slightly barren steep hill-slope no longer appeared to be the beautiful landscape we saw a few hours earlier. The slopes were dotted with multiple gullies bringing down huge volumes of water towards the temporary road built roads that were washed away by the 2014 landslide. Within seconds one of the larger gullies brought down large boulders in a swift muddy flow — known locally as a ‘ledho’ — washing away everything in its path. Nature’s destructive force was overwhelming to watch. Had it not been for a series of gabion walls, we too would have been washed away. Vehicles from both sides came to a standstill. The road to Kathmandu was completely destroyed. We turned around to travel back to Bahrabise only to see the raging Bhote Koshi river change colours from grey to muddy brown, fresh sediment washed down from the steep mountain slopes. 

Oddly, to the people living along the river banks, it seemed a normal monsoon day and life went on as usual; it was a reminder of how resilient the people were despite enduring a multi-hazard environment with floods, landslides and earthquakes.

Locals filled a truckload of boulders: opportunity after the landslides
Photo: Mandira Singh Shrestha

The following day the road was made operational by the road department with the help of a few standby excavators. Along the way we found numerous landslides due to the previous day’s rain. Occasionally we saw locals collecting the large boulders that had come down to sell in local markets. Despite large scale destruction, there are a number of opportunities where communities stand to benefit.

Concerted efforts and actions are needed to minimise the impact of such hazards. While living in hazard-prone areas increases the risk of disasters, proper mitigation measures — for example early warning systems — can ensure timely preparedness and avert risks. An early warning system in the upstream can provide adequate lead-time and save lives and infrastructure from floods. Assessments of risk and vulnerability are required to reduce the exposure of people to these multi-hazards and minimises adverse impacts. The International Centre for Integrated Mountain Development (ICIMOD) in collaboration with the World Meteorological Organization and hydromet agencies from Bangladesh, Bhutan, Nepal and Pakistan has established a regional flood information system to share real-time data and information and promote transboundary cooperation. At the community level, ICIMOD has also piloted a community based flood early warning system.