Whether you drink from your tap, use electricity, or canoe down your local river, chances are you benefit from U.S. Geological Survey's streamgages. What is a streamgage and what does it do? I'm with experts finding out. A streamgage is a simple mechanical device that measures water flow in a river. The streamgage data are utilized in real-time by the National Weather Service to issue timely and accurate river forecasts and warnings necessary to ensure and promote public safety nationwide. We turn on our taps and we don't recognize where that water comes from. Few people realize who supplies their water, much less that they have relied upon a streamgage to ensure that water gets to customers. They're used to turning on their tap to get water without understanding how intricate and involved it is to make sure that tap doesn't ever run dry. The Potomac River, in the background, is shared by Maryland along with Virginia and West Virginia and the District of Columbia. They periodically have disputes that come about. Having gage information helps to resolve some of those discussions. The Western states, which are sometimes drier than in the East, they utilize gages to divide that water amongst the states.

(Lowry) The USGS is critical because they're seen as an impartial third party. Neither state's gonna trust the other one to collect data that wouldn't help their position.

(Hoffman) Drinking water providers need to know the amount of flow to base their treatment. They need to know the loading, how much is coming in, what kind of pollutants they have to address.

(Lowry) Water needs for fisheries and ecological purposes are also critical. The least tern and piping plover are both endangered species that are throughout our area. They need bare sand bars for their nesting. Again, agencies like the Corps of Engineers needs streamflow information so that those nesting habitats will be available. And hopefully, these birds will recover. Streamflow information is critical in situations of drought or low flow as well as high flow or flooding. With climate change, with increasing population resulting in increasing stresses on our limited water supply in this country, water information is becoming all the more important to what we do and to decision-makers nationwide.

(Hoffman) Streamgage information is utilized by engineering firms, consultants, by the federal and state governments as they design projects, such as this bridge in the background. The river has risen to just over 41 feet in 1936 with a flood event. When this bridge was built, they made sure the bridge was high enough. Rowers, like any paddle sport-- anybody using the river, we need to know what the river is doing. There are serious consequences for taking a rowing boat out into water that's too rough or too fast. Into the next decade, I see continuing need for streamgages. I don't think we can reduce them. We probably want more of them. We've got big infrastructure problems in the U.S.-- bridges, highways... all need to be replaced or repaired. We've got to utilize gage information in order to effectively design those replacements and repairs. I think there's a misconception that a gage placed for 15 years provides all the information you need. In fact, we need these gages to be in place for, sometimes, 100 years because there's so much seasonal variability in how water can come off. We might have a dry June or a wet July. No two years are the same. So unless you have the full range of precipitation covered by these gages, you don't have the confidence you really know and can project what kind of water may be coming. Water is probably the nation's most important commodity. It's one that's underappreciated, but it's essential for life. None of us can survive long without it. Knowing water availability in rivers and streams is critical for the national health. Using our streamgages, we can monitor that flow in rivers and know the water availability. It's important in a future with an uncertain climate, as climate change affects water availability in waterways around the country. To learn more about the USGS streamgaging program, visit water.usgs.gov/nsip. That stands for the National Streamflow Information Program. CoreCast is a product of the U.S. Geological Survey, Department of the Interior. I'm Jennifer LaVista.

Funding to purchase and make this educational production accessible was provided by the U.S. Department of Education:

PH: 1-800-USA-LEARN (V) or WEB: www.ed.gov.