This book is a compilation of Philippine regulations on water supply systems. This is an attempt to address the scarcity of such readily available reference materials that will guide a Civil or Sanitary Engineer in the practice of his or her profession in the Philippines, particularly on water supply systems. Since water supply is also the concern of other groups, this compilation is also intended for the use of other related professionals, local government units, planning officers, researchers, policy makers, teachers, consultants, business firms, board examination reviewees, students, and the public in general who may be interested in the field of water and sanitation development, environmental health and environmental management. Important guidelines included in this book are the national standards for drinking water; regulations for water resources, bottled water, water refilling stations, and water utilities.