GUWAHATI, Nov 22 - Anthropogenic interferences in the natural system are at the root of the problems of flood and erosion that have emerged to a menacing proportion in the State these days, said Chief Secretary VK Pipersenia. He was inaugurating a two-day workshop on application of bioengineering techniques for mitigating riverbank erosion, organised by the Assam State Disaster Management Authority (ASDMA) here today.
�Erosion occurs essentially due to the increased load of silts on the rivers and these silt loads find their way to the rivers from the hills due to denudation. Geo-engineering solutions are virtually no solution, as, until you reduce the silt loads the geo-engineering structures are not going to help the people in their fight against erosion,� he said, setting the tone of the deliberations at the workshop.
The ASDMA organised the workshop with the objective of understanding the causes, factors and situations responsible for the Brahmaputra riverbank erosion hazard, to analyse the success and limitations of the present erosion control mechanisms implemented by the Water Resources Department, the Brahmaputra Board and other organisations and to analyse the best practices on riverbank erosion control using bioengineering techniques through case studies/field experiences.
Experts from the United States of America, Japan, Bangladesh and some other parts of the country, besides from the State government departments, are taking part in the deliberations.
The workshop is an outcome of the interest shown by Chief Minister Sarbananda Sonowal, who directed the ASDMA to explore low-cost eco-friendly measures for erosion control to mitigate the riverbank erosion caused by the Brahmaputra and its tributaries.
Speaking on the occasion, Prof Chandan Mahanta from the Indian Institute of Technology Guwahati (IIT G) cautioned against jumping into conclusions abruptly on the efficacy of the erosion control measures. He laid stress on developing local expertise taking into consideration the best practices available in other parts of the globe and underlined the need for a robust Brahmaputra research centre.
The Brahmaputra is a complex river system, reminded the IIT G Professor and said, �You allow the river to flow on as it wants and tackle it very softly applying a bioengineering approach. But, the fact remains that the Brahmaputra cannot be tackled on a piecemeal basis. There is a need to adopt a comprehensive approach to tackle this river.�
Jadab Payeng, the Forest Man of India, while addressing the gathering of experts, laid stress on making the Brahmaputra sandbars green with a cover of indigenous vegetation. The need of the hour is to expand the green cover and to make environmental science a compulsory subject right from the primary level, he said. He also pleaded for a university for teaching environmental science.
Moreover, he said education and forest and environment should be placed under the President�s jurisdiction so as to make them free from political interference.
Making a presentation on bioengineering techniques using vetiver system for slope stabilisation in respect of riverbank erosion, Prof Shariful Islam from the Bangladesh University of Engineering and Technology (BUET) said that growth of vetiver roots is the highest in the sandy soil. Cost of vetiver planting is also very low.
Moreover, vetiver also helps a sustainable economy for the local people. For vetiver farming, they should be motivated, said Prof Islam.
George Koshy, Principal Consultant, Earth and Water, Chennai and Shantanoo Bhattacharya highlighted the application of bio-mimic systems to control bank erosion.