Techniques and Methods

SPARROW (SPAtially Referenced Regression On Watershed attributes) models estimate the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources. Interactive, online SPARROW mapping tools allow for easy access to explore relations between human activities, natural processes, and...

USGS develops and uses “surrogate” techniques to estimate sediment at times when it can’t be physically measured through samples.

USGS collects sediment samples at thousands of locations across the U.S. using nationally consistent methods.

Since the early 1980s the USGS has worked cooperatively with manufacturers to develop and enhance the use of acoustic Doppler instruments for streamflow and other hydraulic measurements. This site provides information on hydroacoustic technology, instruments, and their use.

Harmful algal blooms (HABs) are caused by a complex set of physical, chemical, biological, hydrological, and meteorological conditions. Many unanswered questions remain about occurrence, environmental triggers for toxicity, and the ability to predict the timing, duration, and toxicity of HABs.

The U.S. Geological Survey recognizes the need to provide sediment acoustic training and to develop standardized techniques and practices.

The USGS collects fluvial sediment and geomorphic data and conducts related research at numerous sites across the Nation. This information is essential to informed solutions to sediment-related and overall water resource management issues.

The USGS Quality Systems Branch (QSB) represents the Water Resource Mission Area’s commitment to generating environmental data of known quality. QSB produces water and sediment performance-assessment samples and data to provide the USGS laboratory users, USGS laboratories, and field personnel with quantitative performance information to assess data quality.

The National Field Manual for the Collection of Water-Quality Data (NFM) provides documented methods and protocols for USGS field personnel who collect water-quality data. The NFM provides detailed, comprehensive, and citable procedures for sampling water resources, processing samples for analysis of water quality, measuring field parameters, and specialized procedures.

USGS National Water Quality Assessment (NAWQA) studies require analyses of stream and bed-sediment samples for major ions, nutrients, sediments, and organic contaminants that are consistent across time and space. Procedures have been designed specifically to produce information that is comparable among studies in different parts of the Nation.

USGS scientists are using high-resolution handheld and airborne thermal imaging cameras in groundwater/surface-water exchange studies and other investigations where surface temperature contrasts indicate various hydrological processes. These cameras are used to quickly locate and characterize thermal (temperature) anomalies along streams, lakes, wetlands, estuaries, and across the landscape...

USGS scientists are working alongside university researchers in Alaska to understand how groundwater and permafrost conditions change over time due to seasonal variations and climate change. Changes in permafrost can pose a threat to built infrastructure (like roads, homes, and pipelines) and to valued ecological resources that provide important habitats for wildlife.