A burst pipe is the most expensive plumbing emergency because the damage compounds every minute the water runs. The pipe repair itself costs $150-$500. The water damage from a burst that runs for hours before discovery costs $5,000-$50,000+. Speed matters more than anything -- turn off the main water supply the moment you discover it. The repair is simple. The damage from delay is not. Here is what to expect for the plumbing repair and how to handle the water damage side.