Hydrography
CEGIS research investigates methods to generate, update, and enhance digital representations of the surface water of the U.S. and the territories, known as hydrography.
Hydrographic data is used to make maps and track river and lake contents.
Mapping water
Water has been represented on maps as lines shapes and images for ages.
We still use blue lines for streams and polygons, a shape with a perimeter, for lakes. But now the shapes and lines can have other data attached to them and can change as we zoom in and out as our map view changes. This collective information is known as "cartographic representation."
Water behavior
Using computers to simulate the behavior of water is known as "modeling hydrology."
Modeling surface water has been employed for a long time for things like predicting the risk of floods given a certain amount of rain or how building structures like bridges might impact stream flow.
Research is now underway to predict where streams are instead of how they might behave.
Measuring from a distance
From small cameras to big satellites, remote sensing is an important tool for mapping streams and lakes.
Remote sensing means measuring from a distance. The breadth of our country makes measuring and mapping the ever-changing surface water a huge challenge. Remote sensing increasingly allows us to understand where water is collecting.