The Indus River, the vertebra of our country, runs 3,200 kilometres in total and, if cared for, is capable of providing sustenance to all, from Kashmir to the Arabian Sea. But without the release of freshwater into the Indus, the coastal region of Pakistan is running dry. The fifth-largest delta in the world is shrinking.

A delta is formed at the mouth of a river, when the river sheds its sediment load, before meeting a slower moving water body such as an ocean, sea, lake and sometimes another river.

The currents of a fast moving river eventually become weak, making it difficult for the river to carry its sediment load any further. The sediment is then dropped at a delta, making it a highly fertile area, before the river concludes its journey by joining another water body.

The Indus Delta, this meeting between the Abasin (Pashto for ‘Father of Rivers’) and the Arabian Sea, was once a union of prosperity. Residents there used to be traders, agriculturalists and fishermen. Today, it is home to suffering, despondency and death.

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Spread out in the shape of a fan, the Indus Delta covers an area of 41,440km² and approximately 210km where it meets the sea. It has shrunk manyfold over the decades. It is a complex ecosystem, consisting of swamps, streams and the seventh-largest — and now threatened — mangrove forest in the world.

It is also home to various species of fish and the famous pink Indus dolphin, along with being an important stop on the route for migratory birds. A dying Indus Delta restricts migration and may lead to the extinction of many species of rare birds.

A source of ecological services and economic benefits, the Indus Delta was added as a wetland site to the 1971 Ramsar Wetland Convention, an international treaty for the conservation and sustainable use of wetlands. Pakistan currently has 19 wetlands designated as areas of international importance under the convention, and nearly half of them are under medium or prominent levels of threat.

Villain one: Government

Discriminatory water policies in Pakistan have left the Indus Delta dry. Data reveals that water flow below the Kotri Barrage gradually decreased after the construction of the Mangla and Tarbela dams, except in high flood years.

As per the Water Apportionment Accord of 1991, Sindh demanded at least 10 million acre feet (MAF) of water to be released below the Kotri Barrage. But between the years 2000 and 2010, the highest number was 5.8 MAF in 2008-9, with the lowest being 0.2 MAF in 2004-2005.

The flow of water from the Indus into the delta is controlled through the Kotri Barrage, situated around 174km from the mouth of the river. This flow is now only seen during the rainy season or in high flood years, when surplus water is supposed to be drained below the barrage in any case.

Without the release of freshwater into the Indus — a consequence of the construction of dams — the river loses its velocity by the time it meets the Arabian Sea. In the absence of flowing freshwater acting as a rival shield, opposing saline seawater forcefully invites itself into the delta and hurts the soil, plants, animals and fish species there.

Without freshwater, depleting fish stock and mangrove forests are causing loss of livelihood and food sources for communities dependent on it. 80pc of fish caught off the coast in Pakistan spend at least a part of their life cycle dependent on the mangrove creeks. Freshwater flows are also supposed to help resist cyclones and tsunamis.

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Furthermore, as seawater intrusion submerges and erodes large tracts of land, saltwater starts creeping into the ground aquifers rendering them unfit for human consumption. A direct consequence of all this is migration, generally to already over-populated urban areas.

The link between lack of freshwater flow and seawater encroachment is not rocket science. If I were to take a guess, the government has made a calculated choice to ignore the need of releasing freshwater into the Indus under the pretense of saving it for agricultural needs. If managed properly, there is plenty of water for both.

The Hindu Kush-Karakoram-Himalayan glaciers — our largest sources of freshwater — are melting at an unprecedented rate. Logic dictates that this glacier-melt should be entering into our rivers and creating a surplus. But we are told that apparently Pakistan has no water. If the country can’t manage and conserve water now, imagine what we’ll do once we lose our treasured and neglected glaciers — which we will, as things stand.

While many parts of the country were falling victim to a bogus ‘dam awareness scheme’, the people in Sindh were dreading further water diversion. Inequitable water distribution policies that typically serve the interests of only two provinces are a massive policy failure on the part of our successive governments.

Villain two: Climate change

Climate change has further exacerbated the issue, with rising sea levels a glaring consequence of it.

According to the Pakistan Fisherfolk Forum, sea intrusion has eroded nearly 3.5 million acres of agricultural land since 1956 and more than 2.2 million acres of farmland in the districts of Thatta and Badin. On top of it, mangrove forests that serve as a barrier between the sea and the coastal region and assist in reducing soil erosion, are steadily depleting.

An Asian Development Bank report suggests that sea levels are expected to rise by further 60 centimeters by the end of the century and "will most likely affect the low-lying coastal areas south of Karachitoward Keti Bander and the Indus River Delta." Seawater intrusion will also cause water-logging and large-scale soil erosion in upland areas due to higher tides. The creation of dams on the Indus will drastically aggravate the situation by reducing sediment load and river flow downstream.

Furthermore, reports suggest that by 2050, Thatta will be completely underwater. In fact, many coastal areas in Badin and Thatta have already been submerged by rising sea levels.

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As the third-largest ice mass outside the global poles — the Himalayan-Karakoram-Hindukush glaciers — melt, they may initially bring more water into the Indus Delta (and also fuel sea level rise), but will eventually leave the area at the mercy of rains.

The Indus Delta already experiences low rainfall, with an estimated average of 25cm to 50cm annually. With altered weather patterns, including prolonged heatwaves and persistent droughts, depending on rainfall alone for agriculture in the region is rather impossible.

Erratic, climate change-induced weather patterns — altered precipitation levels, heightened frequency of torrential rains and frequent tropical cyclones — are another episode of misery for the inhabitants of the Indus delta. A five degree Celsius rise in temperature is expected over the deltaic region by the end of this century. This would increase the amount of water required for domestic consumption, animals and crops by almost 1.5 times.

Caught in a unique cross-road between being submerged by seawater and living through a state of drought, the Indus Delta and its inhabitants are suffering the most intense impacts of climate change.

A possibly happier chapter?

The National Climate Change Policy, 2012 acknowledges the vulnerability of the Indus Delta to climate change. When exactly the government intends to adopt the measures mentioned in the policy, though, remains a mystery.

The construction of dikes that work as walls to stop sea intrusion along the coastal belt has been a partially successful measure. They are cheap and effective solutions in the short term. However, the problem is that dikes do nothing to prevent seawater seepage into the ground aquifers.

A Rs125 billion Sindh barrage project was approved by the federal government this August. This would include the construction of a 12-metre-high barrage on the Indus at a distance of 45km from the sea. The project, expected to be completed by 2024, is aimed at addressing the issues of land erosion and degradation due to seawater intrusion.

A sad conclusion

While tireless efforts by some organisations to revive the delta continue, we need to make a promise to ourselves: that other fragile ecosystems in Pakistan shouldn’t end up this way.

In July this year, almost 1,500 farmers marched 140km to Thatta to protest against water shortage in the Indus Delta. They sang a song that translates to: Wake up, O’heirs of Sindhu, save her, help us cross on this broken boat to the other side.

If things don't drastically change, there will be no need for any boats. We’ll have nowhere left to go.

Are you exploring the impacts of climate change in Pakistan? Write to us at prism@dawn.com