BBMB to assess Bhakra Dam hills for landslide risks amid monsoon concerns

Bhakra Beas Management Board (BBMB) is planning to undertake a detailed geological assessment of the hills surrounding the Bhakra dam due to increasing incidents of landslides during the monsoon season. Sources said that the BBMB management is in the process of signing an MoU with Geological Survey of India (GSI) to conduct a comprehensive study of the slopes and hill formations around the dam structure. The Board has already written to GSI, and formalities for finalising the MoU are currently underway.

The hills flanking the dam and the approach routes from Nangal have witnessed recurring landslides over the past few monsoons. Last year, heavy rainfall triggered multiple slope failures, leading to the blockage of both road and railway tracks connecting Nangal to the dam site. The disruptions affected the movement of personnel and essential supplies. Muck and debris from the slopes had even entered the power house complex of the dam. However, the BBMB authorities managed to contain the situation in time, preventing any major operational disruption.

Officials now believe that a scientific reassessment of the slope stability is necessary to avoid future risks. When the Bhakra dam was constructed in the 1950s and early 1960s, the adjoining hills were reinforced using concrete supports and iron bars to stabilise vulnerable slopes. However, nearly seven decades have passed since those reinforcements were put in place. Experts point out that continuous weathering, water seepage, vegetation growth, and repeated cycles of heavy rainfall may have weakened the original protective structures. Climate variability, including more intense rainfall events, has further increased the vulnerability of hill slopes in the region.

The proposed geological survey by GSI is expected to assess rock strength, fault lines, drainage patterns, and slope stability. Based on the findings, BBMB may undertake fresh reinforcement measures to safeguard both the dam and associated infrastructure.

The Bhakra dam, built across the Sutlej river, is one of India’s tallest gravity dams, standing at about 226 metres. The dam created the massive Gobind Sagar reservoir and plays a crucial role in irrigation, flood control, and hydroelectric power generation for Punjab, Haryana, Rajasthan, Himachal Pradesh, and Chandigarh. Its powerhouses together generate over 1,300 MW of electricity, making it a backbone of northern India’s power supply.

The Bhakra dam is located in the lower Himalayan region, an area characterised by young and geologically active mountain formations. The hills around the dam primarily consist of sedimentary and metamorphic rocks that are prone to weathering and erosion. The Shivalik and Lesser Himalayan ranges in this belt are known for fragile slopes, loose debris material, and susceptibility to landslides, particularly during intense rainfall.

Geologists are of the view that slope instability in such terrain can be triggered by natural factors such as heavy precipitation and seismic activity, as well as human interventions like road cutting and construction. BBMB officials view the proposed study as a preventive step rather than a response to any immediate structural threat to the dam. By engaging GSI, the Board aims to obtain expert recommendations on modern slope stabilisation techniques, including rock bolting, retaining walls, improved drainage systems, and bio-engineering solutions.