A Vanishing Delta: How New Canals Could Destroy Sindh’s Coastal Biodiversity

The proposal to construct six new canals on the Indus River to irrigate the Cholistan Desert in Punjab poses a grave threat to Sindh’s already fragile ecology and irrigation system. Historically, Cholistan relied on rainfall and underground reservoirs for irrigation, and diverting water from the Indus to this arid region is widely regarded as unjust, especially when Sindh’s water demands remain unmet.

Any further canals on the Indus would exacerbate the already dire situation in Sindh, jeopardizing the Indus Delta’s future. The Sindh government has expressed profound concerns regarding this project, emphasizing the province’s dependence as a lower riparian region on adequate water flow downstream of Kotri to sustain the delicate ecological balance in the Indus Delta.

The Indus Delta, the fifth-largest delta in the world, is renowned for its rich biodiversity and critical ecosystem services. It supports diverse mangrove forests, fisheries, and serves as a buffer against coastal storms. Despite being designated as a Ramsar wetland of international importance on November 5, 2002, the Delta faces severe degradation due to reduced Indus River flows, sediment shortages, and rising sea levels.

Sindh’s coastal mangroves, which once spanned 600,000 hectares, have shrunk to approximately 88,000 hectares, driven by reduced freshwater inflows, seawater intrusion, and human activities. Upstream water diversions have drastically diminished Indus River flows, failing to meet the 1991 Water Accord’s minimum requirement of 10 million acre-feet (MAF) downstream of Kotri. This has led to salinization, impeding mangrove regeneration. Seawater has intruded 100-120 kilometers inland in coastal districts like Badin and Thatta, while urban expansion around Karachi, including industrial projects at Port Qasim, has cleared mangrove forests for development. Overharvesting for fuelwood and fodder by local communities, alongside pollution from untreated waste and oil spills, has further degraded mangroves.

The loss of mangroves has resulted in a 90% decline in shrimp and Palla fish production, threatening livelihoods of over 100,000 coastal households and reducing natural barriers against storms and flooding. Key species such as shrimp and the prized Palla fish have seen production plummet by over 90%. This decline impacts over 100,000 coastal households that rely on fishing for their livelihoods.

Coastal districts, particularly Badin and Thatta, are witnessing seawater intrusion extending 100-120 kilometers inland. This has salinized arable land, displaced communities, and degraded freshwater ecosystems. Further, this belt is also popular for vital wintering grounds for migratory birds on the Central Asian Flyway, supported by the Indus Delta’s mangroves and wetlands. Over 200 species migrate here annually, including several globally significant birds. Key species include the Greater Flamingo, Dalmatian Pelican, Eurasian Spoonbill, and Black-tailed Godwit. Ducks like the Northern Pintail and Common Teal arrive in large numbers, while waders such as the Kentish Plover thrive in intertidal zones.

Sindh’s coastal wetlands host over 150,000 migratory birds annually, but habitat destruction has caused a 30-50% decline in populations over recent decades. Threatened species, including the Lesser Flamingo and Indian Skimmer, are particularly affected. The loss of mangroves and freshwater flows disrupts their feeding and nesting, worsening their conservation status.

Sindh, as the lowest riparian province, faces severe water shortages due to upstream diversions and climate change, threatening its agriculture and the Indus Delta’s ecology. The 1991 Water Apportionment Accord, which allocates 117 MAF annually among provinces, has been undermined by insufficient flows. From 1999 to 2022, the annual ecological flow downstream of Kotri Barrage dropped to an average of 14 MAF, compared to 40.69 MAF between 1976 and 1998, exacerbating seawater intrusion and land salinization.

The Indus Delta, crucial for supporting biodiversity and over 0.1 million livelihoods, is deteriorating due to reduced freshwater flows. Climate change further worsens the situation, with erratic rainfall, frequent droughts, and increased water demand. This has diminished agricultural output in Sindh, impacting staple crops like wheat and rice. Sindh’s objections to new canal projects under the Green Pakistan Initiative stem from concerns about worsening shortages and violations of the accord’s provisions.

The Indus Delta is more than just an ecological treasure—it is a lifeline for millions of people and a shield against climate-induced disasters. Any proposal that further reduces the river’s flow downstream must be reconsidered to prioritize the survival of Sindh’s coastal biodiversity and the livelihoods it sustains.

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