With the rising population in Pakistan, the country's receding ground water reserves are a particular concern. In a new project in the capital city Islamabad, rainwater is now being harvested to address the problem.
The Faisal Mosque in Islamabad
When heavy rain comes down on the roof of the Faisal Mosque in Islamabad, around 3 million liters of water a day run through its drainage pipes. The biggest mosque in Pakistan and South Asia is no longer only an inspiration for believers, it has recently become a source of people's well-being.
Drainage pipes laid to collect water
Sanullah Aman is the director general of the Islamabad water management wing."We have a very comprehensive plan, that no water should be wasted. We want to save and conserve the water for our future. And for that we have planned rain harvesting. We have started a pilot project at the Faisal Mosque and till now we have been very successful."
While monitoring wells throughout Islamabad over the past two decades, it has been found that the groundwater level has been falling every year by one or two meters. So the Pakistan government in collaboration with the United Nations Develpoment Programme, UNDP initiated the pilot project at the Faisal Mosque to harvest the rain water.
Abdul Majeed from Pakistan Council of Research in Water Resources says, "I installed this project just a few weeks back. The salient feature of this project is that I have installed two bore holes. They are just acting like tube wells. We pump the water in the tube wells but in these bore holes we are letting the water flow through gravity. The immediate result that I noticed was a 14 feet rise in the local water table, after 3 days of rain. So that was a tremendous success."
Water reservoirs in a forest near the mosque
Filtering the rain water
According to Abdul Majeed, the drainage network of the Faisal Mosque was in place before to protect the building from being flooded. But instead of wasting the rain water, the water research expert has invented a new system to convert rain water into clean drinking water.
Hidden under metal lids in a forest close to the mosque, there are huge reservoirs. Here the water is filtered with the help of sand filter-beds. After the filter the water runs down vertical pipes up to the ground water level. According to Abdul Majeed, the Capital Development Authority, CDA is very interested in the project. "Of course the water level will slowly go down again as the water goes into the ground and disappears into different directions.
Drainage network under the mosque
200 million liters needed every day
"So if this technology could be replicated by the CDA all over Islamabad in different places, where they have a dense network of rainfall collecting systems, it would automatically go into the ground and recharge the aquifers.The CDA chairman was very excited after seeing the project demonstartion and said that they would replicate this project at 100 different places in Islamabad."
Islamabad's two million citizens have a daily consumption of 200 million liters of water. Meanwhile, Islamabad's building code has been amended to include rain water harvesting design specifications for buildings with a footprint of more than 400 square yards.
Author: Jutta Schwengsbier/ jb
Editor: Grahame Lucas