Пакистан борется с серьезным водным кризисом, 80% населения которого не имеет доступа к чистой питьевой воде. Более 90% производства зерна в Пакистане приходится на орошаемое земледелие, что подчеркивает незаменимую роль воды в обеспечении продовольственной безопасности. По данным Института водных ресурсов, Пакистан занимает 23-е место среди 33 стран, которые, по прогнозам, столкнутся с эскалацией водного стресса к 2040 году. 

Ресурсов пресной воды больше не хватает для удовлетворения растущего спроса на воду из-за колебаний предложения, вызванных изменчивостью климата и ограниченной емкостью хранения воды (30 дней в году). Этот надвигающийся кризис угрожает сельскохозяйственному сектору, а также промышленным и бытовым потребностям, что делает потребность в устойчивых методах управления водными ресурсами как никогда актуальной.

Потенциал очистки и повторного использования сточных вод огромен

Нетрадиционные водные ресурсы, такие как очищенные сточные воды, представляют собой ценную и надежную альтернативу, которая может быть использована для решения водных проблем Пакистана. К сожалению, Пакистан упускает эту возможность, очищая только 1% своих сточных вод и не создавая основу для повторного использования сточных вод. Сточные воды, если они очищены и используются повторно, служат двойной цели: защите окружающей среды, удаляя опасные вещества, и продвижению социальной справедливости за счет минимизации потерь воды, восстановления питательных веществ, выработки энергии и перенаправления ресурсов. Этот переход от линейного к циркулярному подходу необходим для того, чтобы превратить этот кризис в возможность для устойчивого будущего. 

As per the World Bank Report 2006, around 2,000 million gallons of sewage is discharged daily into the surface water bodies in Pakistan. If treated and reclaimed, wastewater can meet water requirements in areas such as groundwater recharge, construction, firefighting, toilet flushing, vehicle washing, and cooling in thermal plants, in addition to agriculture. Countries around the world, such as the USA, Spain, Australia, China, and Tunisia are using treated wastewater for augmenting the existing water resources and reclaiming essential nutrients present in the wastewater. The usage of treated wastewater for irrigation in Saudi Arabia has saved 60% of groundwater.

Experts call for context specific wastewater management solutions at the Pakistan Water Week 2024

One of the priority research areas identified under the global IWMI Strategy 2024-2030: research and innovation for water security is to reduce water scarcity using circular management approaches. At the Pakistan Water Week 2024 led by IWMI Pakistan, a consultative meeting of experts from UNICEF, GIZ, PCRWR, FAO, NUST, WASA, CDA, and international researchers from Sri Lanka and South Africa IWMI offices, was held to share and explore global solutions for transforming wastewater into a valuable resource. The experts emphasized the need for context-specific solutions tailored to Pakistan's unique challenges. 

Due to the high infrastructure costs of conventional centralized wastewater treatment plants (WWTPs), investing in small or decentralized wastewater treatment and reuse systems presents a practical starting point for resource recovery in Pakistan.

Decentralized treatment systems also support the implementation of the polluter pays principle by fostering accountability through localized mechanisms.

The experts highlighted that mechanized decentralized WWTPs are suitable for urban settings while rural and peri-urban areas could benefit from nature-based solutions such as constructed wetlands. When selecting technology options, it is crucial to incorporate resource recovery, nutrient recycling, and reuse in the design from the outset.

To devise an effective treatment method, a thorough assessment of the contaminant load in the wastewater is essential. 

To ensure the long-term functionality of these facilities, robust operation and maintenance (OandM) frameworks are crucial. Cost-sharing models for capital expenditure (CAPEX) and operating expenditure (OPEX) should be explored to address financial sustainability. Integrating a surcharge within water bills, a practice common in many countries, could provide a consistent revenue stream to support WWTP operations.

For the effective reuse of treated wastewater, well-designed distribution networks must be established to ensure safe and efficient delivery.

A significant barrier to changing the status quo is the widespread lack of understanding about resource recovery and its practical implementation. Advocacy efforts aimed at both the public and government are essential to enhance understanding of treated wastewater reuse and promote acceptance of its benefits by addressing social and religious concerns of consumers. 

Capacity building at the municipal level is crucial by engaging communities through targeted training programs.

Another research area suggested by experts was dry sanitation systems, which conserve water and recover resources by being waterless and energy-efficient, and produce fertilizer as an additional product. Such systems would also help in closing access gaps by providing sustainable sanitation services to marginalized and vulnerable populations with low access.

Farmers in various areas of Pakistan are currently utilizing untreated wastewater for irrigation which poses serious public health risks. Immediate action must be taken to combat the use of untreated wastewater by launching effective awareness campaigns, strengthening regulations, and ensuring the implementation of wastewater treatment standards for irrigation.

Strengthening wastewater management framework is essential to mitigating contamination risks 

Wastewater from industrial, agricultural, and domestic sources often contains heavy metals, which can seep into the groundwater. The IWMI team in Pakistan, under the UK Foreign, Commonwealth, and Development Office (FCDO) funded Water Resource Accountability in Pakistan (WRAP) program, evaluated groundwater quality in District Okara, Punjab, under an extensive water quality sampling initiative.

A total of 151 samples were collected from various groundwater sources, including handpumps, submersible pumps for drinking water supply, and tube wells used for irrigation, across spatially distributed sites to assess physio-chemical and heavy metal parameters. Sample water quality analysis was undertaken at the Pakistan Council of Research in Water Resources (PCRWR). A GIS-based spatial analysis of laboratory results identified significant variations across multiple parameters, revealing five major contaminants - Arsenic, Total Dissolved Solids (TDS), Nitrate, Iron, and Fluoride. Arsenic emerged as the predominant contaminant present in 32.5% of the collected samples, followed by TDS (18.5%), Nitrate (10.6%), Iron (9.9%), and Fluoride (8.6%). The concentrations of these five parameters surpass the World Health Organization (WHO) permissible limits for drinking water quality. 

These contaminants pose significant health risks for communities using groundwater as a source for drinking.

Focus groups discussions were conducted with the Okara and Renala Khurd communities to gauge if the health risks associated with poor water quality were prevalent in the community. Discussions revealed that constipation, stomach pain, nausea, diarrhea, joint pain, fatigue, hepatitis, thyroid problems, and skin allergies were common among the community. To safeguard public health and ensure sustainable groundwater management, Pakistan must strengthen its wastewater management framework through a comprehensive and coordinated approach, including regular water quality monitoring, effective wastewater treatment solutions, community awareness programs, and policy interventions.

Circular solutions for waste management and resource recovery 

Globally, IWMI promotes the circular approach through research focused on cost-effective methods for treating agricultural and septic waste. Drawing from its Resource Recovery and Reuse (RRR) series, IWMI Pakistan aims to explore solutions suitable to the local context for reducing the waste burden. Learning from successful models, such as in Ghana, where fecal sludge is transformed into fertilizer pellets through a public-private partnership, Pakistan can adopt similar initiatives. The aim is to develop a closed-loop system that efficiently recycles resources with minimal environmental impact.

Time to rewrite the narrative

Recycling and reusing wastewater are a critical necessity in the context of rapidly depleting surface and groundwater resources in Pakistan. It offers advantages in improving both quantity and quality of water through reducing groundwater abstraction and preventing untreated wastewater from returning to rivers and seeping into the ground. There is no doubt that Pakistan has a high potential for water recovery, and it should not neglect this opportunity to improve water security. It is time to rewrite the narrative, considering wastewater not as a burden but as a catalyst for a more resilient and prosperous economy.

The Nation