Bottle gulleys and traps are essential drainage components used to manage and direct wastewater from buildings to the main drainage system while preventing foul odors from escaping. Bottle gulleys, typically installed below ground level, collect surface water and wastewater from kitchens, bathrooms, and utility areas, allowing debris to settle and preventing blockages. Traps, including P-traps and S-traps, are U-shaped pipes that retain a water seal to block sewer gases from entering living spaces. Constructed from tough plastic, these components are crucial for maintaining sanitary and efficient drainage systems.