Pakistan wastes 30 to 35maf rainwater annually

FAISALABAD: Pakistan loses approximately 30 to 35 million acre-feet of rainwater annually due to floods and lack of proper storage facilities.

Water management experts suggest that this lost water is equivalent to the total storage capacity of major reservoirs like Tarbela and Mangla dams, and can be preserved by constructing water storage reservoirs or recharge wells. Pakistan receives between 300 to 1,000 millimeters of rainfall annually, and due to climate change, the intensity and frequency of rainfall have increased significantly in recent years.

According to the Meteorological Department, Pakistan recorded 16 percent more rainfall than usual in 2023, while in August 2024 alone, rainfall was 142 percent above normal levels. This highlights the potential of using rainwater for recharging groundwater, which could bring a significant positive change.

Additionally, due to population growth, the demand for daily water consumption in urban areas has increased from 4 million acre-feet to over 10 million acre-feet in the past five years. The continuous extraction of groundwater without recharge is causing its quality to deteriorate and levels to decline rapidly, making groundwater recharge more critical than ever.

Pakistan’s ten largest cities account for approximately 24 percent of the country’s total population, and their annual average rainfall levels are as follows: Karachi (6.87 inches), Lahore (23.9 inches), Faisalabad (13.6 inches), Rawalpindi (37 inches), Gujranwala (22.8 inches), Peshawar (15.1 inches), Multan (4.1 inches), Hyderabad (5.36 inches), Islamabad (31.13 inches), and Quetta (9.6 inches). However, neither federal nor provincial governments nor district administrations have any system in place to store and utilise rainwater in these major cities. Experts claim that over 30 million acre-feet of rainwater in urban areas is wasted every year as it mixes with sewage water and becomes ‘black water’.

According to Dr Rai Niaz, an international water management expert and former Vice Chancellor of Barani University, the amount of groundwater being extracted in cities far exceeds the amount being replenished, leading to rapid contamination and depletion.

He emphasised that instead of allowing rainwater to mix with sewage and go to waste, it can be stored in designated ponds or wells in different areas and even directly channelled underground. The stored rainwater can be used for irrigating parks, trees, and plants. Additionally, households should be required to install rainwater recharge systems that direct rainwater from rooftops into the ground through boreholes, improving both the quality and level of underground water.

New housing colonies can also incorporate these systems at the design stage, ensuring that rainwater is collected in designated locations and stored in wells for gardening or other purposes.

Experts warn that Pakistan’s groundwater levels are depleting by more than one meter annually as the country extracts over 65 billion cubic meters of water per year, while the natural replenishment rate is only around 55 billion cubic meters. Given these alarming trends, urgent measures are needed to store and utilise rainwater in urban areas for daily use and groundwater recharge.