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Data Access Tools

Data Access Tools include APIs and search and query forms. 

Filter Total Items: 461

Hydrologic Unit Maps

The U.S. is sub-divided into successively smaller hydrologic units which are classified into four levels: regions, sub-regions, accounting units, and cataloging units. Each unit is identified by a unique hydrologic unit code (HUC) consisting of two to eight digits based on its classification. This site provides information and data for current and historical hydrologic units, names, and numbers.

From Snow to Flow

A majority of the water in the western U.S. comes from snowmelt, but changes in the timing, magnitude, and duration of snowmelt can alter water availability downstream. This data visualization story explores what changing snowmelt means for water in the West, and how new USGS efforts can advance snow science by modeling snowpack and snowmelt dynamics and linking these results to streamflow.

Multisource Water-Quality Trends in the Delaware River Basin

Water quality is essential for understanding water availability by providing insights into the drivers of change and possible availability constraints. Using data from eight monitoring organizations including the USGS, the Multisource Water-Quality Trends in the Delaware River Basin mapper shows changing water-quality trends from 2008-2018 in rivers and streams across the Delaware River Basin.

Measuring stream flow

In this explorable interactive tool you will investigate a series of charts and sliders to explore how water level, water velocity, number of measurement points and stream channel shape influence stream flow. Great for use in the classroom, especially for student curious about coding.

Lowell Minor Planet Services - asteroid.lowell.edu

The USGS Astrogeology Science Center has collaborated with Lowell Observatory to create a graphical interface for their main asteroid characterization web portal. The portal uses data from the astorb database maintained by Lowell Minor Planet Services.

Data Query for the Water Quality of San Francisco Bay Project

Since 1969, USGS has collected water-quality data along the deep-channel longitudinal axis of the San Francisco Bay-Delta system at 37 fixed locations spaced 3-6 kilometers apart. The Water Quality of San Francisco Bay Data Query provides access to the entire dataset.

Fire Danger GACC Regional Forecast Graphs

The GACC Regional Forecast Graphs provide a look at the most recent fire risk outlook in comparison to historical information.

Fire Danger OGC Services

Fire Danger map services are available as Open Geospatial Consortium (OGC) Web Map Service (WMS) services.

Fire Danger Map and Data Products

The Map and Data Products page offers bulk download of the Fire Danger Forecast data suite.

Download Data & Maps from The National Map

This is the primary search and download application for USGS topographic maps and base-layer GIS data. The same topographic maps are also downloadable through other interfaces.

TopoView - Map Downloader

TopoView shows the many and varied topographic maps of each of these areas through history. This can be particularly useful for historical purposes, such as finding the names of natural and cultural features that have changed over time.

The National Map Viewer

The National Geospatial Program satisfies the needs of customers by providing geospatial products and services that customers incorporate into their decisionmaking and operational activities.