Data Access Tools
Data Access Tools include APIs and search and query forms.
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.
USGS Flood Event Viewer
During large, short-term events, the USGS collects streamflow and additional data (including storm tide, wave height, high-water marks, and additional sensor deployments) to aid in documenting flood events. The USGS Flood Event Viewer provides convenient, map-based access to downloadable event-based data.
Federal Priority Streamgages (FPS) Mapper
This mapper identifies USGS Federal Priority Streamgages (FPS). FPS are monitoring stations that track the amount of water in streams and rivers across the Nation to meet long-term federal information needs. They are strategically positioned to serve as a backbone for the larger National Streamflow Network that is operated in cooperation with over 1,200 federal, state, tribal, and local agencies.
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.
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 Viewer, Map and Data Products
The Map and Data Products page offers bulk download of the Fire Danger Forecast data suite.
Surface Water Flow Trends in the Nation's Streams and Rivers
Changes in streamflow conditions can affect infrastructure, water supply, and ecosystems. The IWAAs Surface Water Flow Trends mapper provides access to information about long-term changes in low flows, mean flows, and peak flows. View national trends for the last 100, 75, or 50 years, or calculate trend values for a custom time period at an individual site.
Hydrogeology of the Adelaida Area, San Luis Obispo County, CA
The USGS is conducting a comprehensive evaluation of groundwater resources of the Adelaida area. Use this map to explore the hydrogeology of the area, including land use, geology, and USGS hydrologic data by watershed or water management district.
TrendPowerTool: A web lookup tool for estimating the statistical power of a monitoring program to detect population trends
A simulation-based power analysis can be used to estimate the sample sizes needed for a successful monitoring program, but requires technical expertise and sometimes extensive computing resources. We developed a web-based lookup app, called TrendPowerTool.
Southwestern Willow Flycatcher Habitat Viewer
The Flycatcher Habitat Viewer was developed to meet the needs of organizations by providing maps of predicted flycatcher breeding habitat throughout its range. Maps are provided from 2013 to present and cover 57 satellite scenes. Maps identify predicted flycatcher habitat based upon the amount of green vegetation within a 120-m radius of each cell, and the size of floodplain within a 360-m radius.
Assessing Phytoplankton and Nutrient Abundance in the San Francisco Estuary and Delta
A data visualizatoin exploring the relationship between nutrient distribution and phytoplankton under different conditions across the San Francisco Delta and Estuary. Assessing distribution and abundance aids understanding of how managing nutrient supplies affects aquatic food webs, helping managers evaluate the potential environmental benefits of future nutrient reduction efforts agains
Decision-Making with the Multiple Objective Vireo Explorer (MOViE) Tool for the Santa Clara River
This tool is constructed around a model that integrates the major factors influencing the continued recovery of least Bell's vireo along the Santa Clara River in California (i.e., habitat quantity and configuration, habitat quality, and cowbird parasitism).