Trading activity on the historic Nathula Pass situated 14,400 ft above sea level in the Himalayan region has started threatening the fragile ecology of the region.
A team of the Central Pollution Control Board, which visited the fabled Silk Route in 2007, a year after it was reopened for cross border trade between China and India, found that expansion of the trade route was disturbing the ecosystem of the area.
"Reopened with an aim to boost trade between China and India, ongoing expansion of one of the world's highest navigable roads is in progress without any precaution of the possible environmental impact," the board said in its latest report.
"Earth cutting for expansion of the route is going on even in high altitudes where many natural water springs have sprung up. The spring water carries away the soil from top and causes siltation in the streams and rivers disturbing the ecosystem," the CPCB said, seeking urgent intervention to check the ecological degradation.
The path, which is being expanded for making it a major Indo-China Trade route, has left the CPCB concerned about the future of ecology in the region.
Expansion of the Route Trading Point is likely to impact on the sensitive Himalayan environment if proper precautions are not taken to safeguard it, it said.
The board said since the route passes through high altitude having limited vegetation comprising short and stunted growth of plants species mainly due to thin top soil of the area, the disturbance will be long lasting.
"The whole ecosystem (flora, fauna, soil, air and water) is no doubt very sensitive to any change of environment. Once this ecosystem is disturbed it will take very long time to recover the original ecosystem or it will never recover," the report warned.
The premier pollution control board has also taken note of the damages being caused by the earth cutting for route expansion on high altitude Tshangu lake situated in the region.
"The Tshangu lake in the area is also being affected by the trade route expansion. The lake is receiving surface rain water from the slightly inclined mountain side where the extension work of the trade route is in progress. There is no arrangement to check the surface water carrying the soil from the earth cutting," the board noted.
It is likely that the depth of the lake will decrease due to siltation of the soil particles carried down from earth cutting. Also, there are no management of solid and liquid discharges from the market places on the bank of the lake, it added.
Trading through the route is done four days a week during May to November wherein four Chinese and Indian goods vehicles each come to Sherathang Trade Mark, an immigration and rest house, five km away from Nathu La Pass under the Sikkim government.
"The solid wastes generated from this trade activity as well from the Trade House is found scattered in the area without management. The wastes including plastic wastes are burnt together in an open area in the back side of the trade House," CPCB said.