The largest source of drinking water for Islamabad is ____?

The largest source of drinking water for Islamabad is ____?

اسلام آباد کے لیے پینے کے پانی کا سب سے بڑا ذریعہ ____ ہے؟
Explanation

Khanpur Dam is a dam located on the Haro River KPK near Potowar Plateau, about 50 km from Islamabad.