downtoearth-subscribe

The earth may shake, but life goes on

The earth may shake, but life goes on RAIN IN the hills usually evokes romantic images. But in the Himalaya, the monsoon often becomes macabre.

It had been raining incessantly through the evening of September 2 and the inhabitants of the seven villages in the Angoth gram sabha of Chamoli district were getting ready to sleep. In nearby Gadni Bazaar, at the confluence of two gadheras (mountain streams), the owners of the 17 shops there downed their shutters -- for the last time as it turned out, because a cloudburst touched off a sudden flood in Meduli gadhera. The furiously flowing waters swept the entire bazaar away and 14 persons sleeping there were drowned.

Floods in the Garhwal region, through which the Bhagirathi and Alaknanda flow, usually occur when tributaries flood the main rivers with enormous quantities of debris from landslides.

The Alaknanda valley has been scourged repeatedly by landslide-generated floods, including an 1893 landslide -- the largest known in the Central Himalaya. It blocked the Birahiganga to form a colossal, 350-metre high dam. A lake, Gohana Tal, behind the dam, sent a tidal wave surging down the valley when the dam collapsed, erasing the entire town of Srinagar, which lay 100 km away. When the wave hit Hardwar, another 100 km away, the level of the Ganga rose by nearly four metres.

Recalling the night Gadni Bazaar was washed away, Chandra Singh, whose house was 100 metres above the bazaar, said, "I woke up to a peculiar rumbling noise. In a matter of seconds, water gushed into my room. I ran outside and leaped up the slope to escape the swirling waters." Besides the bazaar, the flash flood destroyed 27 gharats (water mills), nine bridges and vast number of paddy fields -- all in a few hours. Only five bodies were recovered from the debris left behind.

Flash floods are a natural phenomenon in the region, which is a geologically fragile area. Garhwal residents understand the quirks in their environment and Murali Lal, a social worker in Gopeshwar, pointed out, "Nobody would have built houses at the site of the bazaar, but it was an ideal location for a market-place. We have a Garhwali saying, Nadi teer ka rokda, jath kar saunre paar (Move away from the river, or one day you will have to face its wrath)."

As for the soil conservation department's attempts to check erosion by building bunds, terrace walls and irrigation channels, the villagers are openly critical, and one commented, "They are only contributing towards the instability of the slopes by dislodging and breaking up boulders and rocks in the area and using it to build a bund."
The Uttarkashi earthquake Bhagirathi valley villagers remember vividly the earthquake that devastated the region last October 20. Measuring about 6.6 on the Richter scale, the earthquake left behind a trail of destruction as a reminder that the villagers live in a geologically unstable area. In Jamak, one of the worst-hit villages, the residents refer to the tremor as "Mata ka prakop (wrath of the goddess)".

Discussing the long-term impact of the earthquake in Uttarkashi, Surendra Kumar of Wadia Institute of Himalayan Geology in Dehra Dun, noted presciently in January, "It is too early to realise the gravity of the potential dangers. Probably the next monsoon will bear out the full implications of the fragile state of the hills." When the monsoon broke, the worst fears were realised. Under the force of the showers, unstable slopes gave way and there were many flash floods. Uttarkashi residents became apprehensive of landslides and falling rocks and boulders. "Our experience shows that instances of landslides have increased after the earthquake. Duration of road blocks due to repeated slides have surpassed previous records in Uttarkashi," noted district magistrate Chanchal Kumar Tiwari.

Five consecutive days of rain in January were a sign of what was in store. Life came to a standstill and even relief operations had to be called off because of frequent landslides triggered by the action of the water.

Scientists from all over the country rushed to the area after the earthquake and identified Agora, situated 22 km northwest of Uttarkashi at a height of 2150 metres, as the original point of rupture. Ground ruptures, cracks, fissures and cases of subsidence appearing in the area, indicated the occurrence of a highly localised burst of high-intensity energy.

But few scientists followed up their preliminary survey. Says P N Agarwal of Roorkee University's department of earthquake engineering, "Sustained monitoring and study requires considerable finances. But scientific organisations do not have that kind of input." The result is that little scientific information is available on the earthquake's long-term effects, particularly the ecological effects.

The 1950 earthquake, which devastated the catchment area of the Brahmaputra river in Arunachal Pradesh caused massive landslides which, in turn, increased for decades the silt load of the river and raised the river bed of the Brahmaputra in some areas by a few metres.

The 1991 earthquake, though less intense may also have had far-reaching impact on the slopes and water bodies near Uttarkashi. A K Saraf and R P Gupta of Roorkee University compared before-and-after satellite images and found "definite proof that the earthquake had a marked and immediate impact on the glaciers, vegetation, and on the land mass."

Rains aggravate danger
The 1992 monsoon has made some areas so unsafe, residents, such as those in Saloo village, have already started relocating to safer sites. And, in Agar, Tihar, Siri and a few other villages, the demand for resettlement is increasing. But what has put the district administration in a predicament is a dharna by Khanera villagers, demanding resettlement because about 40 ha of their agricultural land has slipped following the earthquake. One of the officials explained, "This is a new dimension that has been added to the problem after the rains. People are safe here, but their source of livelihood is endangered."

An official meeting was held in Uttarkashi last December to formulate a rehabilitation plan for villages identified as geologically unsafe. Ten villages from Bhatwari block and nine from Dunda were recommended for either rehabilitation or resettlement. But, the district administration have delayed action till after the monsoon, stating in a letter dated August 4, 1992, "The scientists of the Geological Survey of India have warned that after the monsoon, the soil will settle and only after that will it be possible to decide treatment for landslides."

Rehabilitation is going to be difficult in terms of getting land for resettlement, say local officials. In January 1992, the district officials, noting that existing laws can empower the district magistrate to acquire land only during floods have urged the state government to amend the law so it can apply to earthquake areas, too. The officials are also in open confrontation with the villagers, insisting that as "there is no real danger", resettlement of entire villages is unnecessary and all that's needed is for a few families to be shifted within existing village boundaries. Some officials contend the demand for resettlement in safer sites is in pursuit of a desire to acquire land in Dehra Dun or Hardwar.

Angry villagers complain district officials ar indifferent to their plight. On September 3, 1992 those living in Matti filed a petition alleging that the sub-divisional officer in Dunda had offered to relocate only six families though 30 families were endangered by a landslide. PWD officials countered by saying that when they went to the village to build a retention wall, the villagers opposed them saying the wall posed a greater danger.

The natural tension was released in a matter of minutes by the earthquake; the social tensions built up in its aftermath will take much longer to subside.Unstable slopes
Uttarkashi residents can readily recall their experiences when the fateful earthquake struck. In the Maneri area, close to the epicentre, a huge cloud of dust remained in place for a few days and reports of fire and escaping gases poured in from a number of places. Scientists explain that friction caused by landslides was converted into light and it illuminated the cloud of dust, giving it an eerie glow.

A district geological task force headed by geologist N A Ansari surveyed cracks, fissures and landslides following the earthquake and reported a number of settlements were threatened by unstable rock. A crack, 55 cm wide, was declared a potential slide capable of destroying Sungar village and in Kaligaon Paturi, parallel cracks appeared on the hill slopes. A 100-metre-long scar was caused near Pilangarh by a huge slide, which also obstructed the natural flow of Pilang stream and damaged an iron bridge. Another set of cracks measuring upto 100 cm in width, was visible above Kakrati and Burha Kedar, there were three major cracks whose length extended upto 12 km. In the epicentre of Agora, a crack on the hill overlooking the village had assumed dangerous proportions and villagers complained that rock falls were virtually continuous. And, V H Joshi of the earthquake engineering department of Roorkee University, warned, "A huge fissure above Pata village with a reported length of 200 m even threatens the town of Uttarkashi."

His warning reinforced horrifying reports from the area of men and mules being crushed to death by falling rocks. About 150 persons are said to have died in this manner.

Reports of widespread destruction of agricultural terraces have poured in from several villages and loose rock from collapsing terrace risers wreaked havoc with the crops. Some of the terraces in Manpur village still have large cracks and because of them, water cannot be retained in the terraces.

A large number of guhls (irrigation channels) were damaged by boulders tumbling downstream destroying the masonry heads of the diversion channels. In some villages, women have stopped going into the forests to collect fuelwood and fodder after one woman from Dhedsari village was killed by a rockslide in a nearby forest.

Water bodies
In Uttarkashi on the morning after the earthquake, there was panic as residents found the main course of the Bhagirathi totally dry. This was caused by a tributary of the Bhagirathi, called Pilangarh, which contributes about 10 per cent of the discharge into the main Bhagirathi channel, was blocked by a rockslide. The channel remained blocked for a few hours but a timely, natural clearance averted a major catastrophe. "As a precautionary measure," explained U D Gupta, executive engineer of the Maneri dam project, "the dam tunnel was closed and this led to a temporary drying up of the Bhagirathi beyond the power house point in Uttarkashi town." But some environmentalists who visited Maneri dam immediately after the earthquake, insisted the dam tunnel's shutters came down on their own under the tremor's impact. The possibility of a flash flood loomed large again in late July when a massive landslide completely blocked the Bhagirathi near Loharinag, on the Gangotri road. The water level in the river rose about 3.5 metres and created a huge reservoir, which submerged the road behind the slide.

What has not been possible, however, is to avert flash floods in the smaller streams, one of which devastated Dhedsari village (see box). The villagers fear blockage by debris set loose by the earthquake, may yet trigger more flash floods in the area. Ghaveti villagers, for example, have petitioned the district administration saying, "An irrigation channel close to the village is getting filled with debris, which may ultimately give way."

Sediment load
Though possible ecological fallout of the earthquake could be an increase in the rate of siltation of the Bhagirathi, B L Jatana, director of water and soil conservation at Rishikesh, says, "There are a number of reasons that determine soil erosion. In the case of a channel block induced by an earthquake, some impact on the silt load of the river can be expected".

Numerous landslides activated by the earthquake will slowly add to loose debris that will ultimately find its way into the drainage system. The maximum number of slides have occurred along the banks of the Bhagirathi and scientists at the Wadia Institute of Himalayan Geology have reported a collapse of the river's left bank at Gangori.

A meticulous study of the ecological consequences of the earthquake would have helped in the planning of relief and rehabilitation efforts. Meanwhile, the devastated land mass and disturbed water bodies continue as threats to local villages. As Purandas, one of the villagers, puts it, "Mrityu ne to chaaron or se gher rakha hain hamen. Hum kahan bhaage (It is a virtual death-trap for us. Where do we go)?"

Related Content