Saturday, July 25, 2026

Question: How much water does it take to knock an average adult off their feet during a flash flood?

Answer: 6 inches. According to guidelines from the National Weather Service, floodwaters are deceptively strong due to a combination of weight, velocity, and the resistance they encounter. Experts say it takes a mere 6 inches of fast-moving water to knock an adult off their feet in a flash flood situation. It takes just 12 inches of rushing water to carry away most cars and just 2 feet of rushing water can carry away SUVs and trucks.