A cross-connection occurs when a pipe designed to carry safe drinking water is connected at some point to a pipe containing unsafe water or other liquid material. You may not think of your home as having such hazards, but if you have a hose that is submerged in a pool, carwash bucket, bathtub, or laundry sink, or if you have a pesticide sprayer connected to a garden hose, you’ve created a cross-connection. If a water main breaks, the potential exists for unsafe substances to be siphoned back into the water supply. This means that contaminated water in a pool, carwash bucket, laundry sink, or pesticide sprayer could be drawn into the water system. Once there, the contamination could affect many.