Water resources management has grown out of competition for the use of water and the fact that mother nature does not supply water at a constant or predictable rate. Whether for human supply, recreation, or habitat, there are many demands placed on this limited resource. In order to properly manage our water resources, we must have the means to measure them. Stream gages measure the quantity and variability of our surface water resources. In addition, the analysis of streamflow data in combination with groundwater data helps us understand the relationships of the hydrologic cycle. When flooding occurs, stream gages are indispensable as tools for flood forecasting and warning along rivers and streams.

The Delaware River Basin Commission (DRBC) believes that there is a need to increase awareness of the importance of stream gages. The purpose of these web pages is to provide an understanding of what stream gages do, how they work, and who is responsible for maintaining and funding them. Stream gages are a vital tool in our management of water resources. Operation of these gages under the exacting standards of the United States Geological Survey (USGS) provides a consistent set of streamflow data throughout the United States. Reliable funding of the stream gage network is necessary in order to obtain the information needed to make good decisions about the managing of our shared water resources.