Salinity Challenges in Pakistan's Indus Basin

Salinity in Pakistan’s Indus Basin has evolved into a systemic agrarian and environmental crisis, shaped by decades of hydrological mismanagement, climate variability, and intensive irrigation practices that fail to account for natural salt balances. The widespread use of canal irrigation without adequate drainage has accelerated secondary salinization, gradually raising groundwater tables and mobilizing dissolved salts into the root zone. Climate change has further compounded this process through higher evapotranspiration rates and erratic river flows, reducing the natural flushing of salts from soils. As a result, large areas once considered fertile have experienced declining crop yields, land abandonment, and rising production costs, directly undermining food security and rural incomes.

Empirical evidence underscores the scale of the problem. The Indus River system transports approximately 31.6 million tonnes of salts annually, of which nearly 20 million tonnes are deposited within irrigated command areas, steadily degrading soil structure and water quality (Qureshi, 2020). According to the Pakistan Council of Research in Water Resources, more than 6.8 million hectares of land are currently affected by salinity and sodicity, with the most severe impacts concentrated in Sindh and southern Punjab regions that are simultaneously critical to national food production (PCRWR, 2023). Conventional remediation approaches, such as gypsum application or large-scale drainage projects, are costly, slow to implement, and often beyond the reach of smallholders.

Against this backdrop, saline aquaculture emerges not simply as a coping mechanism, but as a strategic adaptation and diversification pathway. By utilizing brackish groundwater and salt-affected soils for the cultivation of salt-tolerant fish and shrimp species, saline aquaculture offers a means of converting degraded resources into economically productive systems. This approach aligns climate-resilient development by reducing pressure on freshwater resources, generating alternative income streams, and enhancing livelihood resilience in marginal areas.

The Salinity Crisis in the Indus Basin: Scale, Drivers, and Socioeconomic Consequences

Salinization in Pakistan’s Indus Basin represents one of the most pervasive and persistent constraints on agricultural productivity, arising from an interaction between adverse geo-hydrological conditions and decades of human-induced mismanagement. Naturally saline parent materials, flat topography, and shallow groundwater tables make the basin inherently vulnerable. These risks have been greatly amplified by intensive canal irrigation systems that lack adequate drainage, allowing salts to accumulate progressively in the soil profile rather than being flushed out of the root zone.

Groundwater exploitation is a central driver of this crisis. In both Sindh and Punjab, excessive pumping to supplement canal water has induced the upward movement of saline groundwater into cultivated soils and, in some areas, into freshwater aquifers. The situation is particularly severe in Sindh, where more than 80 percent of groundwater is classified as saline to very saline, rendering it largely unsuitable for conventional crop production and forcing farmers into a cycle of declining yields and rising input costs (World Bank, 2022).

Climate change further intensifies salinity pressures. Higher average temperatures increase evapotranspiration rates, concentrating salts in surface soils, while greater variability in rainfall and river flows reduce the natural leaching of salts. The IPCC (2022) projects that water scarcity and salinization will worsen across arid and semi-arid regions, placing additional stress on already fragile farming systems in the Indus Basin.

The economic and social costs are substantial. Salinity contributes to the annual abandonment of an estimated 40,000 hectares of farmland, undermining rural employment, accelerating poverty, and increasing pressure on urban labor markets (IUCN, 2021). At the national level, yield losses and land degradation translate into billions of dollars in foregone agricultural output each year. Recognizing this threat, Pakistan’s National Water Policy (2018) and National Climate Change Policy (2021) identify salinity as a strategic challenge and call for integrated land-water management alongside the promotion of saline-tolerant livelihood options, including aquaculture.

Harnessing Saline Aquaculture as a Strategic Adaptation Pathway

Saline aquaculture represents a transformative opportunity to convert degraded, salt-affected lands and brackish water resources into productive economic assets. By cultivating salt-tolerant species such as tilapia, mullet, milkfish, shrimp, and certain carp species in water with salinity levels ranging from mildly brackish to fully saline, this approach aligns naturally with the ecological realities of Pakistan’s Indus Basin. Rather than attempting costly and often unsustainable soil reclamation for conventional crops, saline aquaculture works with existing conditions, offering a pragmatic adaptation strategy.

The livelihood potential is particularly compelling. For farmers operating on marginal or abandoned lands, saline aquaculture provides a viable diversification pathway that reduces dependence on climate-sensitive cropping. Empirical evidence from Southern Punjab indicates that fish farming under saline conditions can achieve Benefit–Cost Ratios as high as 2.9 for species such as grass carp, significantly outperforming many salt-stressed crops and offering more stable returns (Gul et al., 2023). This income stability is critical in regions where salinity has eroded agricultural profitability and increased rural vulnerability.

Beyond income generation, saline aquaculture contributes meaningfully to food and nutrition security. Pakistan’s per capita fish consumption remains alarmingly low at around 2 kg per year, compared to a global average exceeding 20 kg (FAO, 2022). Expanding aquaculture production can help bridge this protein gap, improving dietary diversity and addressing micronutrient deficiencies, particularly in rural communities.

Saline aquaculture also delivers environmental co-benefits. Well-managed ponds can improve local microclimates, reduce wind erosion, and, when integrated with salt-tolerant crops or agroforestry, support gradual soil reclamation. Despite these advantages, brackish-water aquaculture remains underdeveloped. Although Pakistan has approximately 80,000 hectares of fishponds, the sector contributes only about 0.4 percent to national GDP, far below its potential and in stark contrast to countries like Bangladesh, where aquaculture has become a major engine of rural growth and export earnings.

Current Status and Evidence from Field-Based Research

Recent empirical research has significantly improved understanding of saline aquaculture’s feasibility and constraints in Pakistan. A comprehensive scoping assessment conducted during 2022–2024 by the International Water Management Institute (IWMI), with support from the Australian Centre for International Agricultural Research (ACIAR), surveyed saline aquaculture practices across selected districts of Sindh and Punjab (Khalid et al., 2024). The findings reveal both promising potential and structural gaps that must be addressed to scale up the sector.

In terms of farm structure, saline aquaculture is largely small- to medium-scale. The average pond size across surveyed farms is approximately 1.66 hectares (4.1 acres). However, there are marked provincial differences. In Sindh, nearly 88 percent of farmers own their ponds, reflecting a stronger tradition of landholding and greater availability of saline groundwater. In contrast, only about 39 percent of farmers in Punjab own ponds, with the remainder operating on leased or shared arrangements, which can discourage long-term investment and infrastructure upgrading.

Species selection is relatively narrow but informed by local adaptability. Tilapia, major carps (Rohu, Silver carp, Grass carp), and catfish dominate production systems. Experimental and on-farm evidence suggests that Silver carp and Grass carp perform particularly well under saline conditions, achieving strong growth rates and favorable economic returns at electrical conductivity levels of 8.5–9.0 dS/m (Gul et al., 2023). This indicates clear scope for developing species-specific production packages tailored to salinity gradients.

Farmer demand for public support is consistently high. Respondents emphasized the need for structured training programs, subsidized access to quality seed and feed, disaster compensation mechanisms especially after shocks such as the 2022 floods and targeted incentives to attract youth into aquaculture. Although interest among women and young people is evident, effective participation remains limited due to social norms, lack of tailored skills training, and constrained access to finance. Addressing these institutional and human capital gaps is essential for inclusive and sustainable sector growth.

Structural Constraints and a Phased Roadmap for Saline Aquaculture Development

Despite its strong potential as a climate-adaptive livelihood, the development of saline aquaculture in Pakistan is constrained by a set of interlinked structural, institutional, and market-related barriers. At the policy level, institutional fragmentation remains a central challenge. Responsibilities for fisheries, water management, agriculture, and climate adaptation are dispersed across federal and provincial agencies, resulting in uncoordinated initiatives, regulatory gaps, and the absence of a cohesive national vision for saline aquaculture. This fragmentation limits scale economies and discourages private sector participation.

Technical and infrastructural deficits further constrain productivity and commercialization. Research on saline-tolerant species, selective breeding, and optimized production systems remains limited, while the availability of quality seed from specialized hatcheries is inadequate. Farmers also face high feed costs and poor access to extension services. Downstream infrastructure is particularly weak: cold chains, processing units, and quality control facilities are largely absent, leading to post-harvest losses and restricting access to higher-value markets.

Financial barriers compound these challenges. Smallholders have limited access to formal credit and insurance, and aquaculture is widely perceived by lenders as a high-risk activity. Without tailored financial products or risk-sharing mechanisms, investment in ponds, aeration, and water management technologies remains subdued. Environmental and disease risks add another layer of vulnerability. Water pollution, weak biosecurity practices, and exposure to floods and droughts undermine production stability and discourage long-term planning. On the demand side, weak domestic market linkages, low consumer awareness of farmed fish quality, and stringent non-tariff barriers constrain export prospects.

Addressing these constraints requires a phased and strategic approach. In the short term (0–2 years), priorities should include targeted capacity development especially for women and youth focused on pond management, water quality, and enterprise skills. GIS-based mapping of salinity hotspots and aquaculture potential, alongside pilot demonstration farms, can build an evidence base and farmer confidence. In the medium term (2–5 years), system strengthening should focus on public–private partnerships to establish saline-tolerant hatcheries, feed mills, and pilot processing units, supported by tailored credit and index-based insurance products. Investments in basic cold storage, transport, and cooperative-based marketing are essential to strengthen value chains. In the long term (5–10 years), scaling and integration require a harmonized National Saline Aquaculture Development Strategy, robust biosecurity and disease surveillance systems, and the development of certification and branding to position Pakistani saline aquaculture products in niche regional and international markets.

Conclusion

Salinity in Pakistan’s Indus Basin represents one of the most persistent and structurally embedded challenges to agricultural sustainability, rural livelihoods, and national food security. Conventional responses aimed at reclaiming salt-affected soils have proven costly, slow, and often inaccessible to smallholders, underscoring the need for alternative, context-appropriate solutions. Brackish and saline aquaculture offers a pragmatic and forward-looking adaptation pathway, one that works with, rather than against, prevailing ecological realities. By converting degraded land and saline water into productive assets, saline aquaculture can diversify rural incomes, reduce pressure on freshwater resources, and contribute meaningfully to food and nutrition security.

Empirical evidence from Pakistan demonstrates that saline aquaculture is economically viable, nutritionally valuable, and socially relevant, particularly in salinity-prone regions of Sindh and southern Punjab. However, realizing this potential at scale requires overcoming deep-rooted institutional fragmentation, technical and infrastructural deficits, financial constraints, and market limitations. A phased development strategy anchored in capacity building, public–private partnerships, tailored finance, and coherent national policy emerge as essential for long-term success.

Ultimately, saline aquaculture should be viewed not as a niche activity but as an integral component of Pakistan’s climate-resilient agricultural transformation. With sustained political commitment, coordinated governance, and inclusive investment, it can evolve into a resilient livelihood system that enhances rural stability, strengthens food systems, and turns the salinity crisis into an opportunity for sustainable growth.

References: FAO; Gul et al; IPCC; IUCN; Khalid et al; PCRWR; Qureshi; World Bank.

Please note that the views expressed in this article are of the author and do not necessarily reflect the views or policies of any organization.

The writers are affiliated with the Drainage and Reclamation Institute of Pakistan (DRIP), Pakistan Council of Research in Water Resources (PCRWR) and can be reached at nazargul43@gmail.com

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