25% Rainwater Harvesting Enough to Sustain Groundwater: IWMI Official
ISLAMABAD, (APP - UrduPoint / Pakistan Point News - September 19, 2026) Dr Mohsin Hafeez, Global Director for Water, food and Ecosystems at the International Water Management Institute (IWMI), has stated that capturing just 25% of annual rainfall can substantially alleviate groundwater depletion and mitigate urban flooding in Islamabad.
He shared with APP that IWMI successfully demonstrated an innovative groundwater recharge model at Kachnar Park, Sector I-8, accumulating over 566,000 litres of rainwater at a single site within four years while enhancing groundwater levels and quality.
The pilot project was implemented at a flood-prone area where surface runoff from a nearby parade ground frequently inundated surrounding areas during the monsoon season. A small recharge pond was constructed to trap the flow, allowing water to naturally filter through layers of sand and stones before replenishing the aquifer.
Dr Hafeez explained that the site is equipped with advanced monitoring tools, including a real-time rain gauge, water flow meters, and groundwater sensors, enabling researchers to gather scientific data on groundwater recharge and quality for the first time in Islamabad. Data collected since June 2022 reveals that the project has successfully recharged more than 566,000 litres of water and elevated the local groundwater table by approximately 4.5 mm, while maintaining water quality.
Inspired by these outcomes, the Capital Development Authority (CDA) approved 100 groundwater recharge sites across Islamabad in 2024, subsequently expanding the initiative to another 100 sites. Currently, around 200 recharge sites are operational throughout the city.
Beyond enhancing groundwater recharge and mitigating rainwater flooding, these initiatives have relieved pressure on stormwater drainage systems. Residents living near recharge sites report reduced flooding during monsoons and increased water availability from household boreholes, allowing them to access groundwater for longer periods daily.
Dr Hafeez noted that IWMI's research indicates that harvesting one-fourth of Islamabad's annual rainfall is adequate to stabilize groundwater depletion. The project's success has significantly influenced public policy; the CDA now incorporates groundwater availability assessments into its by-laws, making them mandatory for new housing schemes.
In collaboration with the Pakistan Engineering Council (PEC), Pakistan Council of Research in Water Resources (PCRWR), and other stakeholders, IWMI also contributed to the development of Green Building Codes requiring rainwater harvesting systems in newly constructed buildings.
Moreover, the Federal Cabinet, under Prime Minister Shehbaz Sharif, approved the Green Building Code of Pakistan and Rainwater Harvesting Provisions in a significant step towards sustainable water management practices.