STEVE INSKEEP, host:
Huge parts of this country are preparing for spring floods. The Northeast had a rough winter which left big snow packs in the mountains ready to melt. In the Midwest, some rivers are already filled, which adds to the importance of the work we're going to hear about next. Researchers are wading into the water in hopes of improving flood warnings. NPR's John Nielsen joins some flood chasers on a river in southern Indiana.
Mr. BOB HOLMES (Hydrologist): Okay. We're started.
JOHN NIELSEN: What's the water speed?
Measuring a river while it's flowing all around you can make nailing jello to a wall look easy. But flood chasers have their ways.
(Soundbite of motor)
NIELSEN: Huddled inside a beat-up 18 foot aluminum motorboat, a team of hydrologists from the U.S. geological survey is about to pull a bunch of high tech gizmos through the muddy waters of the White River. Doppler guns, says Bob Holmes, they map the speed and the direction of hidden currents.
Mr. HOLMES: Every half of meter, we're getting three-dimensional velocity all the way through the water column and all the way across, so we have literally hundreds of observations of velocity and depth before we get to other side.
NIELSEN: Holmes says flood chasing can be a risky job, but he also says it's essential to collect information from as many swollen rivers as possible. He says that makes it easier to figure out exactly how fast a particular river is rising and to predict how long it might be before the towns downstream could face a full-blown flood.
Mr. HOLMES: 'Cause you got to remember, even though it's not devastating flooding here on the White, this feeds into the Wabash, which then feeds into the Ohio, which then feeds into the lower Mississippi, sort of like dominoes, if you blow it on the upper end, that kind of cascades on down.
NIELSEN: Within hours, the data gathered by this team could be in the hands of flood experts at the National Weather Service. They combine it with satellite readings and rainfall predictions. The result is often a timely warning that can save lots of lives like this one from Southern Indiana.
Unidentified Male: River flooding will occur along portions of the Wabash, lower wide and east fork of the White River through mid-week. See latest flood statements.
NIELSEN: Actually the information gathered by the flood chasers is used for more than warnings, towns and cities use it to figure out when it's safe to swim in big rivers and when it is not safe for power plants to pull water out of small ones. Jan Crider, a flood expert with the Indiana Department of Homeland Security says she wants to start using this information to help predict the ways in which new developments might make floods bigger and more dangerous.
Ms. JAN CRIDER (Flood expert, Indiana Department of Home Security): Because as communities develop, waters get to the rivers faster, so it tends to make the height and the level of the water go up faster. So places that had never flooded before, are probably flooding now.
NIELSEN: But flood chasers say it's been getting harder to collect this information. Here in Indiana, flood chasing teams have been getting smaller due to budget cuts. About a dozen hydrologists now keep an eye on more than 200 different waterways. At the same time these researchers are struggling to maintain the state's 170 stream-high cases. Most of those gauges are locked inside big, rusted metal boxes that look a little bit like fortified port-a-potties.
Mr. HOLMES: Well let's see what we got inside here.
NIELSEN: A group of USGS researchers recently checked out this gauge on a river in northern Indiana after it started sending question marks up to a satellite instead of water level readings. It turns out the wires have been eaten by mice, but Robert Holmes of the USGS says mice may be the least of the threats faced by the river chasers.
Mr. HOLMES: You can get a beaver chewing on lines, a satellite antennae can get shot off with a deer slug, we've got gauges that you have to be very careful when we go into them, make sure our cars are plainly visible, our vehicles, because we've had people shoot deer slugs through the doors of the gauging stations.
NIELSEN: Holmes thinks people would be a lot more respectful of these gauges if they knew how often they helped people get out of the way of floods. Already, he says, the gauges have helped give early warning of two big floods in Indiana. He's worried that this spring, there could be many more to come.
John Nielsen, NPR News. Transcript provided by NPR, Copyright NPR.