The fate of the Indus

Climate change is the latest threat to the Indus, and without immediate attention, there will be hell to pay

In May 2022, reports began to emerge that the cotton crop in Sindh was wilting. In Sanghar, one of the largest cotton producing districts in Sindh with cotton grown on 300,000 acres of agricultural land, less than 200,000 acres were being used to cultivate cotton. And on the 200,000 acres that were being used to grow cotton, crop performance was abysmal. Over the past 10 years, according to figures available with the Pakistan Cotton and Ginners Association, Pakistan’s cotton yields have fallen by 26% from 880 kg per hectare to 652 kg per hectare over the last decade. While the cotton crop in Sanghar suffered, other agricultural areas dependent on the down-river water from the Indus were affected as well. In Thatha, fishing villages were left without any source of livelihood as the nearly three kilometre stretch of river that crossed the region dried up completely and was replaced by huge deposits of sand. At the Kotri Barrage of the Indus in Sindh, water levels had fallen from 15,000 cusecs of water to barely over 2000 cusecs. Figures from May this year showed that a major dip in the Indus of 10,000 cusecs (an outflow of 105,000 cusecs on May 19 and 95,000 on May 20) occurred at Tarbela dam, raising fears that the dam may have hit dead levels. Its inflows plunged to 77,900 cusecs on Friday from 98,000 cusecs on May 14. These flows are to be used Taunsa upstream in Punjab and in Sindh. The dam’s level stood at 1,406 feet on May 20 against 1,414 feet on May 16. All of these are signs of the times. For decades, the Indus River has been suffering. Since the middle of the 19th century, it has undergone severe changes due to the development of the Indus Irrigation System, the building of dams and barrages. Since the 1947 partition, the Indus River Treaty of 1961 has also contributed to the unnatural ebbs and flows of the river. All of these have had adverse effects on the water levels of the river and its different tributaries, and in turn has had an effect on the country’s agriculture. Now, however, we are beginning to see the emerging effects of climate change as well. In addition to the many historic reasons for the state of the Indus River, climate change is causing direct consequences already, adding another layer of complexity to an already troublesome issue. As climate change continues to wreak havoc on both lives and livelihoods, its effects are only just making themselves known. Over the decades to come, unless dire actions are taken, things are only bound to get worse. About 50 million years ago, in the Mesozoic era, the shallow sandy Tethys Sea upfolded and formed the Great Himalayan Ranges because of the collision of the Indian plate and the Siberian plate. The Indus basin comprised lofty Himalayan mountains in the north and flat plains of Punjab and Sindh in the east and south. These mountains with immense snow cover gave birth to the Indus River and its tributaries.

The river originates from Lake Mansarovar in Tibet, China, which stretches over 3200 kilometres. It flows through the Hindukush, joined by tributaries from Gilgit, Swat and Kabul, before flowing into the Punjab near Kalabagh. This is where five different freshwater tributaries which give the Punjab its name — Jhelum, Chenab, Ravi, Beas, and Sutlej — join the Indus before flowing together in a single mighty river all the way down Sindh and into the Arabian sea.

For centuries this has been the flow of the Indus. It has changed course, warped itself around cities, and spurned them when they have grown too large. It has, at the same time, been open to the manipulations of human civilization.

Since the middle of the 19th century, the construction of dams, barrages, and canals to divert the maximum river water for irrigation resulted in drying up the natural pathways of the rivers, except during monsoon season. “The aquifer in the irrigated areas became high and created problems of waterlogging and salinity, but due to extensive groundwater extraction, the water table near urban centres is lowered now. Water quality was degraded due to addition of fertilisers, pesticides, chemicals, municipal sewage, and industrial effluents,” says an article titled “Vulnerability of Environmental Resources in Indus Basin after the Development of Irrigation System,” published by the World Bank in 2019.

In the British era, the irrigation system was developed to increase crop production in order to develop the agriculture-based economy, which turned the basin into a densely populated area. Food demand and British economic interests in the agricultural products, specifically cotton, were a major driving force for the development of an extensive agriculture system in British India. By the development of irrigation systems and introduction of fertilisers and pesticides, agricultural production increased many folds. This extensive human intervention in the Indus basin resulted in the adverse effects on the ecosystem of the Indus plain from the Himalayas to the Indus delta.

Between 1872 and 1929, the British rulers built weirs across all the eastern tributaries of the Indus to divert the river water into canals. Weirs were also constructed on the Kabul and Swat rivers and on three sites on the Indus itself and its inundation channels. Most of the upper Indus plain, thus, received perennial water and the desert was brought under the plough. Because the irrigation system was such a huge success, areas that were formerly rainfed now became dependent on river-water.

After partition, and the Indus River Treaty of 1961, Indus River System (IRS) was developed into a complex network of canals, and 74% of its water was utilised for irrigation. Since 1947, the Indus irrigation network has been continuously extended, and cropland area has increased from 8.5 to 18.2 MH in Pakistan and 2.02 to 8.5 MH in India, according to the earlier mentioned report.

It has never remained a single entity. Like all great rivers, it has shifted course and brought both destruction and life with it. The river has been unpredictable in its moods, but the one thing it has always been has been reliable in is the amount of water it has been providing. A large reason for that reliability has been that, according to a book titled “Irrigation” edited by Sandra Ricart, Antonio Rico, and Jorge Olcina, the Indus gets “more than 50% water from the glaciers followed by well-defined monsoon system in the upper catchment during monsoon season.”

Enter climate change

This was a very brief history of what has happened to the Indus since the middle of the 19th century. The point is not to say that the Indus was destroyed by the Indus Irrigation System or that it was a mistake. On the contrary, the irrigation system and the changes the Indus has undergone is testament to its adaptability. The number of dams and barrages built on the Indus have generally been identified as a major reason for the end of communities in the deltaic region dependent on the Indus. One example is Keti Bunder, which lies to the east of Karachi. This was once a bustling port and trading centre with a population of 40,000, but is today a ghost town with most of its population moving to more economically viable areas. Shah Bunder tells a similar story, as do several other port towns which once dotted the coast.

However, the Indus has never been a monolith. It has never remained a single entity. Like all great rivers, it has shifted course and brought both destruction and life with it. The river has been unpredictable in its moods, but the one thing it has always been has been reliable in is the amount of water it has been providing. According to a book titled “Irrigation” edited by Sandra Ricart, Antonio Rico, and Jorge Olcina, the Indus gets “more than 50pc water from the glaciers followed by a well-defined monsoon system in the upper catchment during monsoon season.” This explains why it is reliable.

Line-graph-shows-the-Indus-River-water-flow-rate-from-Kotri-barrage-during-the-period

While it has faced both natural and human changes, the Indus has thrived off the basis of these glaciers. With climate change knocking on the door, that too might be a thing of the past. It is an issue facing many of the rivers that are fed from the Tibetan plateau. Mountains are the water towers of the world, especially in the case of Asia, whose rivers are all fed from the Tibetan plateau and adjacent mountain ranges. More than 1.4 billion people depend on water from the Indus, Ganges, Brahmaputra, Yangtze, and Yellow rivers which are fed by these water towers. Upstream snow and ice reserves of these basins, important in sustaining seasonal water availability, are likely to be affected substantially by climate change, but to what extent is yet unclear.

What is clear is that the early effects are already visible. In an article published in the journal for Global and Planetary Change, a report on the state of the Tibetan Plateau published a few years ago reads that the region has faced “evident climate changes, which have changed atmospheric and hydrological cycles and thus reshaped the local environment.” The report claims that “the Tibetan Plateau (TP) exerts strong thermal forcing on the atmosphere over Asian monsoon region and supplies water resources to adjacent river basins, and the effect of climate change on this region will have an impact on the Plateau energy and water cycle.”

What does this mean?

According to a 2020 study on the threat of climate change to the Indus Water Treaty, climate researcher Rameez Mohib Bhat explains that climate and water have a close relationship, and depend on each other. Any change in climate affects water resources and alters water levels. On the one hand, climate change causes a rise in temperatures which means greater evaporation off the river’s surface, leading to more humidity and stronger and more destructive monsoons. On the other hand, the melting of the glaciers that feed rivers like the Indus also has an adverse effect.

“Scientists have predicted a decrease in precipitation over the lower Indus Basin leading to drought-like conditions and an overall warming effect. Although the forecasts of climate change for the region may not be completely reliable, it is largely predicted that trends will continue towards this pattern,” says Bhat. ”Extreme flooding in the basin also leads to chaos on farms and in communities along riverbanks. Flooding transforms the soil and makes surrounding areas more vulnerable to erosion and degradation, resulting in the pollution of waterways and a reduction in agricultural productivity.”

The results of studies have not been encouraging. An analysis of the melting rate of glaciers entering the Indus Basin is limited due to the inaccessibility of the Himalayan Mountains and high altitudes. However, forecasts obtained using the hydrological modelling approach in combination with the calculation of the mass balance of the glaciers show that the most probable glacial scenario as a result of a “decrease in mean upstream water supply from the upper Indus”.

Himalayan glaciers, an important source of rivers in South Asia, have lost more mass since 2000 than in the entire twentieth century, according to a report from the International Food Policy Research Institute (IFPRI). Meanwhile, a Dutch study predicts that a reduction in glaciers would reduce the Indus flow by 8% by the year 2050. The reduction would be extremely detrimental as the Indus River is the main source of water for all downstream areas. All of this will have a major impact on agriculture.

According to Bhat, Pakistan’s position is precarious because it relies entirely on the Indus River system and has no other alternative if the Indus were to run short. Agriculture accounts for 23% of Pakistan’s national income and about 68% of the rural population depends on it as a source of livelihood.

“Water stress will increase, as the population and demand for water grow but supply

is no longer increasing,” says Bhat. “Reduced water availability for irrigation due to reduction or reallocation of the flow of water may happen for the following reasons. A reduction in groundwater resources, a decline of reservoir storage due to sedimentation, a rise in environmental flow and growing urbanisation which increases domestic and industrial demand for water. Furthermore, it is estimated that the number of people living in the Indus Basin is likely to rise to 400 million by 2050 as compared to 300 million people today,” it reads.

The effects - the example of cotton

Here is the situation in short. Over the centuries, the Indus changed course many times, like mentioned above, but always remained consistent in the amount of water it supplied. However, over the course of nearly two centuries, unplanned irrigation, badly placed dams and barrages have all caused the river to become erratic. With the threat of climate change looming over the Indus, the river may be in for some trying times in the days to come, and the consequences will be widespread. Due to a lack of data, it is difficult to determine how much of the Indus’ current plight is due to climate change, but if immediate steps are not taken, it will not be a pretty picture. The Indus is the spine of the nation’s agriculture, and it being affected by climate change will have a massive impact on the sector. Outside of the Indus, agricultural outputs have already been under pressure because of rising temperatures. Global warming and a lack of advancement in seed science has meant that our crops are not resistant to the rising temperatures and are withering under the pressure. Time series data from 1982 to 2012 for the Punjab province observed that the minimum temperature during February and November considerably impacted the wheat production in rain-fed areas, and had risen over the years by as much as 1 degree. The study found that if the temperature increases by even 3 degrees in 2050, per capita wheat availability may decline to 84 kg per annum from a level of 198 kg per annum in 2012. Similarly, the study also found that water availability and temperature will be key variables for wheat production in the future. This is one small example of how climate change and rising temperatures have had an adverse effect on agriculture in Pakistan. And these are not connected to the Indus River. As discussed earlier, the Indus is facing an existential threat because of the situation of glaciers in Tibet that are its major source. If those glaciers continue to melt at the rate that they are going, the immediate result will be an increase in water supply followed by a steady decrease as the glaciers melt and disappear. Eventually, a few years of massive flooding will be followed by drought.

At the beginning of this story, we discussed how the cotton crop in Sanghar had been affected by a lack of water supply. The cotton crop is not new to these kinds of environmental pressures. The cotton belt of Pakistan, spreading around 1,200 km along the Indus river, faced extreme damages in 2010 flooding. Studies report that nearly 20% of the crop land was completely washed away with the flood water. Loss of production caused the textile industries to rely on the foreign import of cotton to keep their production process smooth. A total of 2 million bales of cotton were destroyed, which affected the competitiveness of textile exports of Pakistan on the global level.

This was at a time when the cotton crop was in harm’s way because of flooding. A similar situation could now, as a result of climactic pressures on the Indus, be happening because of a lack of water. According to the 2012 National Study on Agricultural Investment in Pakistan, “water shortages in Pakistan due to possible drying up of the Indus river would create pressure on food crop production. This will likely divert already scarce water resources to food crop production and would further stress the cotton supply. It is important to note that these reductions in cotton production not only have serious implications for the textile industry but also for the livelihood of millions of people. According to a rough estimate, the textile sector is linked to the livelihoods of approximately 10 million people.”

“Sindh, being at the tail end of the Indus River, is directly impacted by a 60% shortage of water in the Indus, putting at risk the provincial population, agriculture and livestock,” said Sherry Rehman, minister for climate change. “Kotri barrage downstream should have an adequate 15,000 cusecs of water, but instead less than 2,000 cusecs are being released. It is a grave calamity to see that there is no river flow after Kotri. Due to this severe shortage, farmers are dangerously at a risk of losing their cotton, rice and other crops in Sindh,” she added.

“Policymakers need a better understanding of why the flow of the River Indus to the sea is important. It is not a waste. If freshwater does not flow towards the delta, there is a huge loss of biodiversity, culture, and heritage. Rehabilitation of the Indus ecosystem and flow would be a solution where interprovincial efforts would be seriously required,” she explained. “We need to give this mighty river its flow back, and clean it off toxins. Like all great rivers, we will give its own species rights and declare it a living entity with its own environmental rights, which is being done for big water bodies and rivers in the world. If the Indus is at risk, Pakistan is at risk. The Climate Ministry will work on a Recharge Indus policy and report back with an action plan for the provinces.”

Conclusion

In May this year, the ‘Global Food Policy Report 2022’ warned that summer heatwaves are projected to increase at a rate of 0.71 day per decade in Pakistan, while in India it is estimated to triple or quadruple by 2100. The report’s conclusions were that Pakistan’s water supply woes were going to worsen because of climate change. Climate change presents immediate and long-term challenges for South Asia such as glacier melt, sea-level rise, groundwater depletion, extreme weather events, and frequency of natural hazards that are likely to worsen in the coming decades. This is a problem faced in unison by the Global South, particularly South Asia. In Pakistan, where the entire agricultural set-up is based on one river, it is a terrifying realisation that climate change permanently altering the river could have long-lasting effects on our food security and largely agrarian economy. What is needed is immediate action. Whether that will happen or complacency will continue is anybody’s guess. n