A culvert balloon is a durable inflatable plug designed to temporarily seal culverts, pipelines, storm drains, and sewer lines during maintenance, testing, repairs, or emergency situations. Made from heavy-duty rubber or reinforced PVC, it expands when inflated to create a tight, leak-resistant seal, preventing the flow of water or other liquids. Culvert balloons are available in various sizes to fit different pipe diameters and are widely used in construction, civil engineering, municipal drainage, and utility maintenance projects.