Common User Questions

Are you wondering how to use StreamStats?

A gray background can mean one of two things. Either you are zoomed in beyond the maximum resolution allowed for your chosen base map, or the web service providing the base map layer is experiencing issues.

Streamflow statistics are one of the primary products delivered by StreamStats. Here we've provided information about how StreamStats estimates these statistics for user-selected sites.

The StreamStats Application provides two primary products for its users. These products include streamflow statistics and basin characteristics. Read on to learn how these products are used.

StreamStats version 4 is a map-based web application that incorporates a Geographic Information System (GIS) to provide users with access to an assortment of analytical tools that are useful for water resources planning and management, engineering and design purposes.

StreamStats offers a variety of streamflow statistics and basin characteristics but because the application is built on state/regional data, the products offered for each will vary.

The most recent interpretive statistics that are available for streamgages within a state generally are in reports that are cited on our State and Regional-Based Info page for that state, if that state has been implemented. The State and Regional-Based Info page can be accessed through our left-hand menu or directly at https://www.usgs.gov/streamstats/state-and-region-based-info.

The blue pixelated lines are what we call the "stream grid" or "synthetic stream grid", which are used mainly as a guide for delineation. If you click off of these lines, your delineation may only include a few grid cells near the point you clicked. The grid lines are not visible until you have reached zoom level 15.

If you are trying to delineate a basin near a confluence, we have a few tips to help you select the tributary, the mainstem, or both.

Cross-hatching on a StreamStats map are how we represent areas we want to exclude or limit functionality. We refer to them as Exclude Polys and you'll see them labeled this way in the map legend.

The regression equations that are used to estimate flow statistics for ungaged sites were developed using computed streamflow statistics and measured basin characteristics for a selected group of streamgages, in other words, a small sampling of streamgages. These small samplings cannot capture all of the variability in a region.

The accuracy of drainage-area delineations for small areas depends on accuracy and scale of the elevation data used in StreamStats for the delineations. The elevation data that StreamStats uses for most areas are from the USGS 3D Elevation Program dataset, which is a seamless national elevation dataset that is refreshed regularly as new data are made available.

The short answer is: it depends which tool you use.

StreamStats is still expanding to new areas but if your state/region isn't included, here are a few other options that may help.

StreamStats is still expanding with new states/regions. If you are looking for a study area that doesn't exist in the interface we can provide direction on how to get your desired study area implemented.

StreamStats makes it easy to gather data for un-gaged sites. We also make it easy to cite the data you use.

The StreamStats application uses a generalization process to reduce the resolution of a basin for display purposes. Rest assured the computations are calculated on the full-resolution delineation.

Have you ever wondered where StreamStats users are delineating basins, what size of basins are being delineated, or how the data are being used?