Despite being the country with the lowest carbon footprint, Pakistan experienced one of the worst climate change induced flash floods of its history. Rather than being reactive, the authorities must become climate proactive to adapt to the new reality of climate change.
The recent unprecedented floods in Pakistan were caused by heavier than usual monsoon cycle, believed to be due to rise in sea water temperature and excessive and consecutive heatwaves in the southern parts of the country in May and June. The rise in temperatures also triggered glacial flooding in Gilgit-Baltistan (GB).
Pakistan Meteorological Department (PMD) forecasted about 40% above normal rainfall all over the country during 2022 monsoon season. However, the rainfall received were around 208% above the normal across the country. Province wise, the rainfalls were 515% above normal for Sindh, 476% for Balochistan, 87% for Punjab, 45% for Khyber Pakhtunkhwa and 129% for GB. The highest rainfall recorded in the last 70 years was about 700 mm in Larkana Division of Sindh and about 500 mm over the eastern part of Balochistan resulting in severe flash flooding in these areas. Heavy rains all over Sindh worsened the situation due to flat topography and lack of adequate drainage.
According to Pakistan’s National Disaster Management Authority (NDMA)1, the floods have affected more than 33 million people with 1,663 deaths including 614 children. Overall 12,865 people were injured. Around 663,869 people are living in temporary camps. Infrastructure damages included destruction of 410 bridges, 13,074 km roads and more than 2 million houses. The floods also caused partial damage to 1.2 million houses. It is estimated that over 1.1 million livestock and over 2 million acres of crops and orchards were destroyed.* The Government of Pakistan has estimated a loss of over USD 30 billion so far from flooding across the country. Sindh and Balochistan are the most affected provinces in terms of human and infrastructure losses.
Climate change has become one of the most important non-traditional security threats and is directly linked to water and food security of the country. Climate change was given a serious thought at the global level when an international environmental treaty to combat "dangerous human interference with the climate system" was adopted and enforced under the United Nations Framework Convention on Climate Change (UNFCCC). Since then, the Intergovernmental Panel on Climate Change (IPCC), the Kyoto Protocol and Conference of the Parties (COPs) have been warning the countries and nations across the globe to take climate change seriously. The UN agencies and scientists from Pakistan and from around the world have been warning that Pakistan is among the top ten most vulnerable countries to climate change. They have been urging to develop climate-smart and eco-friendly infrastructure, agriculture and industry, preparedness for climate adaptation and resilience, climate proofing, and climate financing to mitigate the climate change and its impacts.2
Lessons Learnt from 2010 Floods
The main causes of 2010 floods were: (i) record-breaking extreme precipitation; (ii) high flows in the Indus River and its tributaries; (iii) infrastructure development in floodplains; (iv) improper drainage system in Sindh; (v) debris and high sediment loads in flood waters changing the rivers’ morphology; (vi) neglect of hill torrents; and (vii) lack of watershed management activities.
After 2010 floods, Pakistan’s National Climate Change Policy was approved in 2012, which helped efforts to raise the awareness and recognition of climate change at the top political, bureaucratic and professional levels. Similarly, the National Water Policy 2018 and National Food Security Policy 2018 were also approved, all of which recognize climate change as the emerging issue and proposed solutions to cope with it.
Pakistan Meteorological Department (PMD) forecasted about 40% above normal rainfalls all over the country during 2022 monsoon season. However, the rainfalls received were around 208% above the normal across the country. Province wise, the rainfalls were 515% above normal for Sindh, 476% for Balochistan, 87% for Punjab, 45% for Khyber Pakhtunkhwa and 129% for GB.
The above actions after the 2010 floods appear very well taken. However, the issues of implementation hampered the achievement of the policy vision. Also, the lack of awareness at different levels of society did act as an impediment in being a climate adaptive nation. During the 2010 floods, maximum damages were caused by the high flows in the rivers whereas during 2022, maximum damages have been caused by the hill torrents.
After the 2010 floods, Lahore High Court established a Judicial Flood Inquiry Tribunal, which in its report, greatly emphasized the importance of managing hill torrents.3 The Tribunal made the following recommendations:
▪ It is recommended that the government sets up Hill Torrent Management Policy as soon as possible and preferably before the start of the flood season 2011. This will not only act as a flood mitigation measure, but will also bring agriculture and prosperity to the “barani” area in the foothills of the Suleman Range.
▪ A detailed audit be conducted before the next flood season to assess the allocation and utilization of funds and verify the results achieved through various heavily funded hill torrent projects done till date. The audit must give elaborate reasons why these projects failed. The audit report must be put up before the Chief Minister of the province so that firm action be taken against the delinquents and the road to flood and hill torrents’ management in this country be paved in stone, once and for all.
▪ Large quantity of fresh water resource that comes down as hill torrents is not being tapped and harnessed. In the modern water scarce world, this passes for criminal neglect. There can be no other national or provincial priority more urgent and pressing than finding ways and means of conserving freshwater resources of our country. The sustainability of our future generations depends on the water management and planning we do today.
▪ Any future Flood Management Plan will be incomplete without Hill Torrent Management. Detailed planning and mechanism is provided in FFC's Manual. Government needs to start implementation”.
Similarly, the National Water Policy 2018, National Food Security Policy 2018 and National Climate Change Policy 2012 place great importance on the management of hill torrents.
Watershed management is one of the most important components of the entire water cycle. It prevents soil erosion and regulates the water that flows to the streams and to the rivers as surface and subsurface flow. Over time, watersheds of all the rivers and streams have been modified due to urbanization, development of infrastructure (roads, and bridges, etc.), cultivation of crops, cutting of trees, and over grazing etc.
Climate change has become one of the most important non-traditional security threats and is directly linked to water and food security of the country.
The same is also true for all the urban centers. With the modification of watershed/catchment areas, the runoff potential has increased manifolds and the lag time (the time taken between peak rainfall and peak discharge) has been reduced. It means that at a particular point (confluence), the runoff reaches much earlier than before with compound effects. The channels or streams (even if those are well maintained and are in their original condition) carrying the runoff water would not be able to discharge it, resulting into ponding and overtopping of the streams. Moreover, sediments in the flowing water increases current of the water many times and changes morphology of the streams/rivers. Any encroachment in the carrying channels in the form of construction or solid and/or wastewater further reduces the carrying capacity. This is what exactly happened at E-11 Sector Islamabad on July 28, 2021, and caused urban flooding in many other cities including Lahore, Quetta, Karachi and Hyderabad.
The Way Forward
Following are the focus areas that outline the way forward for the nation to take.
Water Storage Capacity
In the wake of climate change, floods and droughts have become a concurrent phenomena. To cope with these challenges, one of the most important ways is to regulate the flow of water within the years, within the seasons and within the regions. Provision of water to irrigate crops in Rabi and early Kharif entirely depends on storage and its optimal reservoir operation. Particularly, storage on Indus is essential to control floods in the downstream areas because storage and then controlled release of water in the Indus River will allow more water to be drained from its tributaries and from the hill torrents. Moreover, storage is also required due to reduction in reservoirs’ capacity of Tarbela and Mangla dams due to sedimentation. Therefore, storage capacity of the country needs to be enhanced by constructing large, medium and small dams where possible.
Watershed management is crucial as it helps regulate water within the catchment area and outside it by reducing the sediment and velocity of flow. It should be an integral component of all hydropower and hydraulic structures. Long-term programs of watershed management would bring tremendous results in controlling and mitigating floods. Moreover, controlling grazing in the catchment areas is very important to reduce degradation of the watersheds.
Mangla Dam watershed management program that lasted for 45 years is a classic example of watershed management. Its positive effects became apparent when the annual silt load entering the reservoir was found to have been reduced by almost half, thus doubling the lifespan of the reservoir. Increasing the effective life of a reservoir indirectly helps in attenuating flood flows that are routed downstream. It is rightly said that watersheds are the first line of defense against climate change, heatwaves, soil erosion, droughts and floods.
All the three national policies mentioned earlier place great emphasis on watershed management. The National Water Policy 2018 highlights the importance of: (i) improving watershed management through extensive soil conservation, catchment area treatment, preservation of forests and increasing forest cover; (ii) identification and protection of watershed management zones in upland areas; (iii) promotion of re-afforestation, soil conservation and improvement in land use in the watersheds; and (iv) promotion of studies of integrated watershed management for sustainable upland development and poverty reduction. The National Climate Change Policy 2012 emphasizes on promoting integrated watershed management, including ecological conservation practices in uphill watersheds, carrying out afforestation programs in the barren and degraded lands as well as uphill watershed areas to control sediment and various types of soil erosion, identifying and declaring uphill fragile watershed areas as sensitive and bringing them under special silvicultural management to check floods and siltation of water reservoirs. The National Food Security Policy 2018 focuses on the promotion of integrated watershed management for livelihood improvement in the mountainous areas.
Hill Torrent Management
As discussed earlier, previously major investment has been on building and maintaining the irrigation infrastructure, neglecting the rainfed and hill torrent areas. The recent floods have shown the vulnerability and potential of these areas. If managed properly, these areas could contribute significantly towards achieving the food security besides controlling floods and mitigating the impacts of droughts. What we require is a paradigm shift from building infrastructure (roads, and buildings, etc.) to water resources development, management and better governance in the Indus Basin and the areas outside the Indus Basin. Moreover, in the light of the recent unprecedented high rainfall (both duration and intensity), the hydrologists and engineers need to relook at the peak flows while designing the hydraulic structures and other related infrastructures.
Building Eco-friendly Cities
As discussed before, unplanned expansion of cities, cutting of trees for the construction of roads, buildings and related infrastructure are converting the eco-friendly lands to concrete jungles, ultimately reducing the recharge to the groundwater and increasing urban flooding. As a consequence, besides land subsidence, the groundwater is depleting in almost all urban centers. For example, in Islamabad, inspite of the fact that it receives an annual rainfall of over 1400 mm, groundwater is depleting at a rate of about one meter per year; in Lahore it is depleting at a rate of half a meter whereas in Quetta valley, the groundwater is depleting at a rate of about six meters per year.
The world is now moving from the concept of smart and high-tech cities to the forest cities where climate-smart housing, water (lakes and ponds) and trees (forests and national parks) are the main components. These cities have lot of aesthetic value as well besides having the benefits of controlling heatwaves, air and water pollution, droughts and urban flooding, besides improved physical and mental health of its residents.
Rainwater harvesting and artificial groundwater recharge should, therefore, be an integral part of all urban expansions, housing societies, and residential/commercial sectors. Imagine a small lake in the city where all the storm water (from rooftops, pavements, and roads etc.) of the area is diverted. Besides providing recreational activities, these lakes would control flooding, absorb heat, change the microclimate of the area, increase biodiversity and improve the aesthetic value of the areas. Artificial groundwater recharge also offers huge socioeconomic and environmental benefits by recharging the depleting groundwater aquifers, protecting the water from evaporation and pollution and controlling the urban flooding.
Pakistan Council of Research in Water Resources (PCRWR) has developed simple, smart and cost-effective rainwater harvesting, rooftop rainwater harvesting and groundwater recharge technologies that are now being adopted by many national and provincial institutions. The Council has built more than 100 rainwater ponds in Cholistan desert. Following it, the Cholistan Development Authority has also developed an almost similar number of ponds in the desert. Now after every 10 to 15 kilometers in the desert, there is a pond that provides water to the local community (mostly nomads), their livestock and acts as a buffer against climate change and droughts besides improving the microclimate and biodiversity. These ponds have practically stopped migration of the people and livestock which was a common feature before, resulting into a huge loss of human (mostly infants) and animal lives.
With the technical support of PCRWR, the Capital Development Authority (CDA) is installing 100 recharge wells in Islamabad.4 Moreover, UNHABITAT is installing 5,000 rooftop rainwater harvesting systems in Nowshera and Rawalpindi districts where the Council is providing technical assistance for the proper design of these systems. However, there is a need to adopt this technology at a larger scale due to its multiple benefits. For this purpose, these technologies should be given legal cover such as by including them in the building codes of Pakistan Engineering Council.
Proper Drainage System
Appropriate drainage system is very important, particularly for the lower Indus due to relatively flat topography and high water tables. With high water tables, there is less or no capacity of the soil to absorb water. Four districts on the left side of the Indus River (Shaheed Benazirabad, Sanghar, Mirpur Khas, and Badin) are covered by the network of Left Bank Outfall Drain (LBOD) consisting of Kadhan Pateji Outfall Drain (KPOD) and Dhoro Puran Outfall Drain (DPOD). These drains are connected to the Tidal Link system and is the only source for the disposal of rainwater into the sea on the left side of the River Indus. Due to inappropriate design, siltation and poor maintenance, the LBOD overflowed, causing widespread flooding in the adjoining areas. Moreover, the LBOD was also breached at several locations. Therefore, rainwater could not be disposed of timely through this poorly maintained drainage system.
On the right side of the River Indus, western boundary of Sindh is connected with Balochistan through Kirthar hills. The flash flood caused by the torrents, after impacting vast areas of Balochistan, entered Sindh. This flood water joined Nai Gaj River and inundated parts of Larkana Division, Hamal Lake, Dadu and Jamshoro districts, draining off through Right Bank Outfall Drain (RBOD) system to Manchar Lake and finally to the Indus River. Since RBOD-II is not connected to the sea, therefore, the flood water could not be drained and as a result, huge number of people, crops and infrastructure were impacted. According to Provincial Disaster Management Authority, Sindh (September 12, 2022), more damages have been reported on the right side of the River Indus.
The above analysis of causes and effects, and the discussion on the mitigation measures suggests that proper basin wise flood management measures should be taken into account from upstream to downstream. Reactive, single, isolated or piecemeal solutions will neither be effective nor sustainable on the long-term basis.
Climate change has become a reality and a non-traditional security threat. It has and is taking its toll in the forms of droughts, heatwaves and floods. The country needs to look into its strategies and move from a reactive to proactive approach, from disaster response to disaster preparedness, climate change response to climate preparedness, climate resilience to climate adaptation, smart, high-tech concrete to eco-friendly forest and lake cities. The federal and provincial governments need to shift their focus from infrastructure development to climate proofing and climate financing, water resources development and management, particularly at the catchment/watershed levels. Moreover, hill torrents which offer a huge potential for harvesting need to be managed on priority. Drainage system in the country, particularly in Sindh, should be well maintained to dispose off any excess water.
The writer is Chairman, Pakistan Council of Research in Water Resources, Islamabad.
E-mail: [email protected]
1 National Disaster Management Authority (NDMA), Report 89, September 19, 2022.
2 Ashraf. M. (2021). Changing Climate and Its Implications for Pakistan. Hilal Magazine, August 2021, pp. 65-68.
3 Report of the Judicial Flood Inquiry, Tribunal on the causes of major breaches in River Indus during the “exceptionally high floods” of 2010. Available at: https://lhc.gov.pk/system/files/flood_report_2.pdf
4 Ashraf M. (2021). Recharging aquifers for sustainable groundwater management. Hilal Magazine, November 2021, pp. 41-44.
* Note: Updated figures as of September 27, 2022.
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