After the widespread destruction wreaked by the 2010 floods in Pakistan, it took the government five years to devise a comprehensive national flood protection plan. This ten-year plan envisioned several new infrastructural interventions including the construction of more embankments, dikes, spurs, retaining walls and diversion channels. This plan also identified the need to improve the largely neglected national drainage infrastructure. Many of these ambitious plans, however, remained confined to paper.
The massive devastation caused by the 2022 floods again prodded policymakers to reiterate the need for Integrated Flood Risk Management, which proposed pursuing a blend of ‘hard’ infrastructure and more nature-based solutions to minimise flood damages. Yet, the lack of attention paid to implementing such a holistic strategy was again evident given the havoc wreaked by the current monsoonal floods.
It is time for our policy planners and implementers to take the need for flood mitigation more seriously. Nature-based solutions merit particular attention as they offer the possibility of bolstering flood resilience without requiring a lot of capital, which is often secured via taking on more foreign loans. Pakistan already has some flood diversion and storage infrastructure in the form of barrages and canals, but these structures are heavily geared towards enabling irrigation rather than flood absorption. Varied experts have recommended building more flood retention reservoirs and reviving natural floodplains to ecologically manage the increasing intensity of climate charged monsoonal floods.
Attention has also been drawn to the possibility of channeling floodwater into ponds, wetlands or artificial lakes. ‘Floodwater harvesting’ or ‘managed flood retention’ can reduce peak flows downstream, thus lowering the risk of destructive floods. This stored water can then percolate down to aquifers via recharge basins to replenish depleted groundwater reserves and be pumped out for use during dry months. These are not merely theoretical suggestions.
Adelaide in Australia has created many recharge basins. Pakistan now seems poised to do the same via the ‘Recharge Pakistan’ initiative, which finally began its implementation phase last year. One major activity of this initiative is to create recharge basins and retention areas across DI Khan, Ramak, Manchar and Chakar Lehri watersheds. Lessons learnt from these efforts must be used to create replicable retention models which can be scaled up significantly to curb flooding.
Major rivers like the Indus carry enormous flood volumes, so creating a small number of small ponds or other retention areas will not be enough. Floodwater is also silt-laden, so ponds and artificial lakes will also silt up quickly and thus need regular maintenance. Also, creating new flood retention areas may require resettlement of communities, which is always a contentious process. However, these are not insurmountable problems, and adopting such nature-based solutions is much less damaging and disruptive than creating more concrete-laden dams or barrages.
Other innovations worth paying attention to include Chinese ‘sponge cities’ which aim to integrate green infrastructure (parks, wetlands, permeable pavements, green roofs) to absorb, store and reuse urban floodwater. In Karachi, some ‘sponge city’ principles are being piloted to reduce urban flooding. Lahore has set up some underground rainwater storage tanks as well. And Islamabad has established several groundwater recharge wells. If these initiatives yield positive results, then housing societies and commercial buildings could be required to invest in such measures to better manage flash floods and help stabilise urban water tables.
The private sector and civil society can also step forward to help devise more small-scale flood retention areas. Cumulatively, such efforts have the potential to not only make Pakistan more climate resilient, but more water secure as well.