Muhammad Luqman

Pakistan is ranked among the countries worst hit by the climate change phenomenon. Rising temperatures and extreme weather events like heat waves and storms have become the new norm in this part of the world. Intense but brief rainfall spells usually turn the roads and streets of cities like Lahore into mega lakes within a short span of time.

 With rapid urbanisation, the situation has turned worse. The combination of concrete structures in catchment areas, encroachment of waterways and outdated drainage systems cause flooding in cities. Urban flooding not only causes traffic jams and immense inconvenience to residents but also puts an additional burden on the country’s already strained exchequer as huge amounts are spent on reconstructions and repairs.

Such an alarming situation demands an adaptive response to climate change, with a strong focus on effective rainwater management, especially the techniques like the rainwater harvesting systems such as rooftop rainwater harvesting, rainwater reservoirs, recharge wells, recharge pits, etc. Lahore Development Authority (LDA) and its subsidiary, the Water and Sanitation Agency (WASA), have launched a rainwater harvesting project in the metropolis, which receives an average annual rainfall of 758.8 millimeters.

“We have completed three rainwater reservoirs in Lahore, i.e., Lawrence Road, Alhamra Cultural Centre and Qaddafi Stadium. These water tanks have the capacity to store rainwater up to 1.6 million gallons,” Managing Director WASA, Lahore, Ghufran Ali, told WealthPK. He said that similar water tanks were being built at the Walled City locality of Sheranwala Gate, Waris Road, Garden Town, Cooper Road, Rasool Park, Karim Park, Tajpura, Farrukhabad, Allama Iqbal Town and Jauhar Town.

WASA built the first ever rainwater reservoir in Lahore at Lawrence Garden in 2020 to collect rainwater for reuse and reduce flooding in the city. Similar water tanks have also been constructed in Rawalpindi, which receives more rainfall than other cities in the Punjab province.

However, the water management experts, while supporting the construction of rainwater tanks in the city, suggest the development of low-cost rainwater storage areas such as depression grounds as well as artificial recharge wells as these initiatives can store rainwater and replenish the aquifer.“The infrastructure presently being developed by WASA to store the rainwater is not sufficient,” said Dr Sohail Ahmad Naqvi, a water resource management expert.

Talking to WealthPK, he said that the best way was to recharge groundwater with the collected rainwater, instead of collecting it in tanks for reuse – which requires resources for treatment, pumping and conveyance. “Recharging is cost-effective, and can help address urban flooding and improve the water table,” he said. Naqvi said that Pakistan would have to follow countries like Australia, Brazil, India, Japan, and Sri Lanka, which have introduced regulations to make rooftop rainwater harvesting (water collected from rooftops) mandatory in certain regions or for specific types of buildings.

“Pakistan needs to enforce similar regulations for public and private buildings — exceeding a certain plot size — in cities to direct collected rooftop water into boreholes and recharge wells to replenish overstretched groundwater resources,” said Naqvi, who is also the director of WWF-Pakistan. He said that rainwater harvesting can be carried out for the agriculture sector too by constructing small and mini dams, especially in the areas like Potohar region of Punjab province.

“The Punjab government has already provided subsidies for such structures in some northern districts,” he said. He said that international donors such as the World Bank and Asian Development Bank can provide financial assistance for such a project.

Credit: INP-WealthPk