 Flash floods, one of nature's most terrifying forces. Every year they kill hundreds of Americans, drive thousands from their homes, destroy billions of dollars worth of property. Flash floods spare no one and no place. They happen in every state in the Union, on city streets, by rural streams, in mountain canyons, from heavy rain overhead, or from storms miles away. These are a few examples. July 1976, 139 people drowned or were crushed to death when 12 inches of rain fell in six hours, sending a wall of water plunging through Big Thompson Canyon, Colorado. August 1985, Cheyenne. 12 died in the biggest natural disaster ever to hit Wyoming. Many were trapped in cars on streets and roads when seven inches of rain fell in two hours. June 1986, Pittsburgh. Nine died, millions in damage. Five inches of rain fell in 90 minutes. And then in May and July of 1987, flash floods turned placid streams in and near San Antonio, Texas, into raging monsters. Charles Lovett and his son Charles Jr. were caught in the first one. The biggest realization that happened for me was that that water was such an awesome power, that that water could swell up against the side of the truck and totally carry us away. Trucking two human beings and knowing, I guess, that we had no control over the situation, you can't imagine that water can have that kind of awesome power. As we came over the top of the railroad tracks and saw the water situation, I saw what appeared to be a little Toyota pickup that had just driven through it. Turns out that Toyota pickup had actually made a U-turn and had driven away, thinking that it couldn't get through from the other end. But I thought, geez, if that Toyota can get through, no problem, I can get through. We started down, I saw some, further saw some people up here on the knoll here that were filming it, and I thought, boy, you know, geez, they're not making any gestures at all, there's really nothing to worry about, and I'll charge through it. And I tried to charge through the water, and I got about right here when the truck just stopped, stopped dead, and I panicked a little bit here, and it started to move a couple of inches, a couple of feet. As we moved down into the stream here, and we started to get carried away, it wasn't a floating sensation, it was if we were completely out of control, and that it was like a little teeny toy being bounced around by fabulous waters, you can imagine a little teeny top being in a toilet bowl. Few people appreciate the power of running water. Even fewer may realize how fast water can rise in a small stream. Jimmy Claus knows. He found out in his own backyard in suburban Pittsburgh during a heavy rainstorm. My mother decided to move her car because the water started coming up in the driveway there a little bit, so she moved her car, and I thought I'd better do the same, so I backed it out the driveway, by the time I got to the end, the car was floating already towards the creek, and I tried to open my door, but it wouldn't open due to the water pressure around it, so I jumped out the window, and I was trying to make it back to the house, I couldn't make it, so I grabbed the tree branch, and just as I grabbed it, I went underwater, and I pulled myself back up and climbed the tree. My car went back and hit the wall, stood straight up on end, flipped upside down and took off, and I found about a mile down the road the next day. I was probably up there an hour and a half, and as the water kept rising, I kept going up a little higher, a little higher, and so I was pretty close to the top of the tree, and the debris was slamming into the trunk, and the tree was rocking and shaking and creaking and everything else, which had me really scared. Architect Ron Duke had an equally horrifying experience at his home, near the headwaters of the Guadalupe River in rural Hunt, Texas. The house itself is built 16 foot up in the air on pilings, and is approximately 200 to 225 foot from the Guadalupe River. It is 3 foot there about above the 100 year flood plain. The night of the flood, I had gone to bed approximately 10 o'clock after watching the evening news and indicated on the weather channel and local weather, that there was a thunderstorm about 50 miles west of here, near a town of Junction, Texas. At 2 o'clock in the morning, I woke up and heard a loud noise beneath the house. I walked downstairs to see what was taking place, and at that point realized that there was a thunderstorm, and there was 2 to 3 foot of air between me and the Guadalupe River. When I was out on the deck here, about half of the deck collapsed, and I was thrown into the river, dropped into the river, grabbed a next piling and pulled myself back up on, and eventually it got to about a foot and a half above the actual deck portion, which would place at approximately 22 foot rise at this point of the river right here. I had no earthly idea that water could rise that fast. The time limit that was involved from 10 o'clock of going to bed, where there was no rain whatsoever, and 2 o'clock, and close to 20 foot of water in a given area, was beyond imagination. I absolutely scared to death, never been so frightened in my entire damn life. Downstream, the flood surged across a field and caught a school bus convoy leaving a summer camp. John Patton, National Weather Service hydrologist, describes what happened. By the time the last bus and van reached this gateway, the river had risen high enough that it trapped the bus and van. 43 young campers and counselors had to exit the van into the cold churning waters. The river would continue to rise over the next hour, reaching a crest of 30 feet near 9.40 a.m. that morning. This 30 feet was 12 feet above the point on which I'm standing, the same height this surveyors rod is. The campers and the bus were swept into the raging floodwaters. The lucky ones were carried into trees where they could take refuge. Army, Red Cross and police helicopters swarmed to the scene and began plucking the teenagers from the river. But 10 were drowned. The seams speak for themselves. Michelle, were you stuck in a tree? Yeah. How long were you in there, sweetheart? About an hour. About an hour? But what's going through your mind right there? I'm scared. Terrified because I can't swim. We prayed a lot and sang, just talked. We started crying because we was thinking of the other people's lives that had been taken that we saw float down the river. If these scenes convey some of the horror of being trapped in flash floods, remember, the worst ones could never be photographed. Listen to two Colorado residents describe the big Thompson Canyon flood. He took his wife and two children out the back door, put them in the pickup and he turned around to go back to lock his door and the wall hit. It slapped him up against the back of his house. He grabbed the gutter and pulled himself up out of the water, spent the night on his roof. And it wasn't but a few minutes, the whole front of his house tore off. But his wife and children were gone. My wife, he saw my wife come out of my garage and my scout and just like, this is fast as you could say. Scared, they were all gone. First came the law in front of the turn and then came the life gas tanks off the campers and stuff and then there came the saw logs and the wood piles and then came the cars and the trucks and the campers and cars had lights on them and the people in them and the lights are still on them. There was people in them and you couldn't even get close to this because of all the debris coming down. There's no way to help any of them. No way, no way. You couldn't even hear them screaming, thank God because the roar was so bad. A flash flood is an elemental force of nature. In most cases, there is nothing we can do to prevent them. But we can help people avoid being trapped and killed. And we can help them save at least some of their property. Meteorologist David Sisk of the National Weather Service describes what has been done in the Pittsburgh region. Beginning in 1980, the National Weather Service in cooperation with the state and counties in western Pennsylvania began installing the new sophisticated automated radio rain gauges in six counties in southwestern Pennsylvania. It collects rainfall on a real-time basis. Looking at the gauge at the top, the rain falls into the funnel. It's collected inside when enough rain is collected of approximately five one-hundredths of an inch. The tipping bucket tips sending a radio signal to a county tower where the rainfall is stored in a computer and then pulled. With the use of the computer terminal here, we can access the automated radio rain gauge data and screening the rain gauge data through the various counties. We can take a look at rainfall over an hourly basis or down to even a quarter hour basis and relate that with what we are seeing on our radar screen. We can make use of this data in order to issue watches and warnings to the potlake. A unique system is being developed in Tulsa, Oklahoma. Dr. Ray Jensen of the Applied Systems Institute. This is the Tulsa Environmental Monitoring and Warning System, a system that is being developed for the city of Tulsa. A lot of emergency management agencies or civil defense agencies have the capability to receive the radar information and to display that radar information. But in this particular system, we're able to take the radar information, both the radar echoes that are commonly seen over television and the radar estimated rainfall reports and display that data on geographical areas ranging from the sides of the state down to six by six miles. We are able to get rainfall reports from 31 automatic stations which report from time to time at operator selected intervals, but they don't have to guess in Tulsa anymore about how high the creeks are going to rise. This system has the capability through computer software to input the radar estimated rainfall over a drainage basin into what we call hydrologic tables. These are tables which relate the amount of rainfall to the amount of flooding that would occur in a particular creek in a drainage basin and also the time that will occur. Advanced systems like these will help weather service forecasters predict flash floods and issue warnings. But warnings will do little good unless people hear and heed them. One useful tool, ANOA Weather Radio, that broadcasts weather information 24 hours a day. Some models will emit a loud alarm automatically when danger occurs. Another all-important tool, this list of personal safety rules. Heed warnings of impending flash floods. Many flash floods happen at night when visibility is poor. Evacuate your area immediately when you're advised to. Climb to high ground when a flash flood is upon you. Don't try to outrun it on foot or by car. Abandon your car immediately if water begins to rise over the road on which you're driving. Above all, do not drive across a flooded road in your car or truck. Many try it. Some don't make it. How can a foot or two of water cost you your life? Water weighs 62.4 pounds per cubic foot and typically flows downstream at 6 to 12 miles an hour. When a vehicle stalls in the water, the water's momentum is transferred to the car. For each foot the water rises, 500 pounds of lateral force are applied to the car. But the biggest factor is buoyancy. For each foot the water rises up the side of the car, the car displaces 1500 pounds of water. In effect, the car weighs 1500 pounds less for each foot the water rises. Two feet of water will carry away most automobiles. There are things we can do to escape the dangers of flash floods. Whatever we do, we should remember that rain will fall again and in a flash, turn tiny streams into raging floods, sweeping away buildings, boulders, trees, cars, trucks and people with incredible force. Those who've survived will never forget them. We kept our arms wrapped around the tree for hours just waiting for help. It wasn't but a few minutes the whole front of his house tore off but his wife and children were gone. It was a great big metal building and had to be like about 60 feet long and it was totally wrapped around a trailer truck that was over there. Absolutely scared to death, never been so frightened in my entire life. You can't imagine that water can have that kind of awesome power.