How climate change, dams & silt are choking Punjab’s rivers

THE people of Punjab are once again facing widespread destruction due to floods in rivers passing through the state. Just two years ago, large parts of Punjab were similarly ravaged, reviving memories of past floods in 1947, 1955, 1988 and 1993.

After the 1955 floods, the state government built drains and embankments, and later dams, to regulate water flow. These measures helped for a while, but climate change has worsened the situation. Sudden cloudbursts and torrential rains in the hills and plains, such as those in Himachal Pradesh and Jammu, now trigger floods with little warning.

While Punjab normally receives an average of 550 mm of rain in a year, on a single day — August 28, 2025 — Jammu received 380 mm of rain, resulting in severe floods in the Ravi. On the other hand, cloudbursts in the Kullu and Bilaspur resulted in huge releases in the Beas. This flow of water, carrying silt and debris from the mountains, passes through dams into rivers, causing heavy destruction.

The flow of rivers follows the laws of nature. To understand the science behind the flow of water in the Sutlej, it is important to study the Sutlej Valley Project of 1926, which documents detailed data on levels and distances of various headworks to control the water flow.

It shows that the slope of the Sutlej is 1.78 feet per mile for a distance of 55 miles from the Ropar Headworks to the Phillaur bridge. From there, up to the Harike Headworks, this slope is 1.50 feet per mile, which further reduces to 1.1 feet per mile in a distance of 32 miles from Harike to the Ferozepur headworks. The slope of the river reduces to just one foot from Ferozepur to the Suleimanke headworks in Pakistan (just opposite Fazilka) in a distance of 78 miles.

Thus, due to the very low slope of Punjab’s rivers, the flow of floodwater downstream remains a challenge, causing massive destruction during heavy rains. This is complicated by heavy silt deposition at dams and headworks. As water slows before each structure, silt settles and raises riverbeds, while scouring downstream erodes soil. Over time, this cycle reduces the carrying capacity of rivers, leading to embankment breaches and floods.

Several villages along the Sutlej and Beas have become chronic flashpoints, where silt accumulation causes severe inundation. For instance, the Sutlej water released from the Nangal dam deposits its silt near Anandpur Sahib, where the people have to bear the brunt of floods. Likewise, after the construction of the Harike headworks in 1956, several feet of silt has accumulated upstream in the Beas up to the bridge of Goindwal Sahib.

Decades of silting have also drastically reduced the storage capacity of headworks and dams. For example, the Ferozepur Headworks, which was built in 1928, had a water storage capacity of 24,000 acre feet (one acre-foot is water with one foot depth on one acre). Today, it has been reduced to only about 5,000 acre feet.

The Harike Headworks’ water storage capacity is down from 67,900 acre feet to about 10,000 acre feet. The Bhakra Dam (1956) on the Sutlej, Pong Dam (1972) on the Beas and Ranjit Sagar Dam on the Ravi (1999) were designed with the water storage capacity of 9.34, 8.57 and 3.28 bn cubic metres, respectively. Their storage capacity is down by 20%.

During heavy rains, excess water from dams is released into rivers to avoid risk of dam failure, which can cause unimaginable devastation.

For example, during the 1988 floods, 4.78 lakh cusecs of water passed through the Ropar Headworks on September 26, which increased to 5.74 lakh cusecs by the time it passed through the Harike Headworks on September 28 and the same swelled to 7 lakh cusecs at the Ferozepur Headworks on September 29. Similarly, 4 lakh cusecs of water passed through the Ropar Headworks in 1993.

Today, the condition is such that even moderate releases of 1.5 lakh cusecs in the Sutlej and Beas cause devastation, compared to past floods when much higher flows were absorbed.

Interestingly, an Indus Valley civilisation study shows that over 5,000 years, the Ravi has risen about 50 ft above the original level of Mohenjodaro due to continuous silt deposition.

The solution lies in effective flood management, which depends on keeping the riverbeds silt-free and maintaining river embankments. Silt coming from mountains through rivers and accumulating in the plains is a natural phenomenon. But with dams, headworks and other structures built on rivers, silt accumulation has increased. Thus, continuous cleaning and desilting of all rivers is necessary for maintaining their natural surface level, allowing the smooth flow of floodwater.

The desilting of dams and headworks, though a difficult task, should be a continuous exercise in maintaining the water storage capacity for the benefit of the people. The annual task of strengthening the embankment of the rivers should remain the top priority of every government.

Substantial funds are required to accomplish these projects. This remains a challenge, especially as the financial health of the state is weak. A portion of the state disaster response funds must be allowed for this purpose with a view to preventing floods rather than responding and managing the destruction after disaster has befallen.

The Bhakra Beas Management Board receives management and maintenance funds from the member states of Punjab, Haryana and Rajasthan. Regulating the water released downstream into rivers is also its responsibility. If other states take free electricity and water as products of these dams, they must also help maintain the rivers at their designed water-carrying capacity to prevent and control floods caused by these dams.

There is a protocol for filling the dams, releasing water for irrigation and power needs and controlling water during floods. But it is of the pre-global warming era. Its re-evaluation is needed — as was done after the 1988 floods, when the full filling date of the Bhakra dam was extended beyond September 15 to accommodate the sudden flow of water.

Regular technical evaluation and time-bound actions can solve the flood problem. Political will at Central and state levels is needed to provide leadership and funds. Otherwise, people will keep suffering similar destruction of life and property.

Kahan Singh Pannu is ex-Secretary, Dept of Water Resources, Punjab.