Search Results

No abstract available....

Accurate measurements of suspended sediment, a leading water-quality impairment in many rivers, are important for managing and protecting water resources; however, water quality standards for suspended sediment in Minnesota are based on grab field sampling and total suspended solids (TSS) laboratory analysis methods. These methods have underrepresented concentrations of suspended...

The erosional and depositional characteristics of meandering rivers lead to the formation and maintenance of point bars along the inner banks of meander bends. Point bars are composed of sediment layers in patterns resulting from the rate and style of channel migration, hydrodynamics, and sediment transport and deposition within the...

In early November, 2006, an atmospheric river brought heavy rainfall and high freezing levels to the Pacific Northwest. Without snowpack to buffer the hydrologic response, the storm caused widespread landslides and debris flows in drainages sourced from every central Cascades volcano. At Mount St. Helens, in southwestern Washington State, intense...

The purpose of this study is to assess the precision and accuracy of laboratory laser-diffraction particle-size distribution (PSD) analysis in support of an effort to formally adopt the method for routine use in U.S. Geological Survey (USGS) sediment laboratories. USGS sediment laboratories analyze the PSD of sediment in support...

The USGS Water Mission Area’s Sediment Science Program provides leadership, training, and methods development in fluvial sediment science for the USGS and its external partners. Overarching objectives of the USGS Sediment Science Program (which includes the Federal Interagency Sedimentation Project) include: 1) developing and promoting innovative sediment monitoring techniques that result in cost effective,...

Channel dredging and erosion in the Atchafalaya River basin have resulted in changes to the hydraulic connectivity of this floodplain swamp that have not been previously quantified. In this study, analyses were conducted to determine hydraulic and geomorphic factors that have changed since channel closure in 1962. Results indicated changes...

The U.S. Geological Survey (USGS) in cooperation with the U.S. Army Corps of Engineers (USACE), monitored a sediment flush event from Spencer Dam located on the Niobrara River near Spencer, Nebraska, during the fall of 2014. Data collected during the flush was used to validate a one-dimensional sediment transport model...

Along the San Bernardino Valley, the Santa Ana River decreases in slope, increases in width, and deposits particles from boulders to sand as it loses transport capacity. Episodic rainfalls feed very large winter floods, but dry summer and fall periods lead to extensive dry alluvial reaches due to surface water...

The U.S. Geological Survey (USGS) Geomorphology and Sediment Transport Laboratory (GSTL), in collaboration with the U.S. Army Corps of Engineers Cold Regions Research and Engineering Laboratory (CRREL), acquired remotely sensed data from several Alaskan rivers in 2017 and 2018 with the goal of developing a methodology for measuring streamflow from...

Acoustics and other surrogates can be used to accurately and cost-effectively provide time-series estimates of suspended-sediment concentration and load, which is essential for creating informed solutions to many sediment-related environmental, engineering, and agricultural concerns. Interagency efforts in recent years have advanced the testing, methods development, operational guidelines, and training on sediment acoustics. This extended...

The Salinas River is the largest river in California’s Central Coast region. Groundwater resources of the Salinas River basin are used to meet water supply needs, including crop irrigation and municipal water supply. Two large multipurpose reservoirs also supply irrigation and municipal water uses. Historical imbalances between supply and demand...

Scientific questions regarding the impact of anthropomorphic noise in the marine environment have resulted in an increasing number of regulatory requirements and precautionary mitigation strategies to reduce the risks associated with high-resolution marine geophysical surveys performed in waters subjected to government jurisdiction. An example of regulatory frameworks includes the Marine...

The worst drought in California in over 1,200 years occurred between 2012-2017 (Griffin, 2014), depleting surface water and groundwater supply and drying out the soils past wilting point. In the summer of 2015, the Jerusalem and Rocky fires burned roughly 40,000 acres within the Cache Creek watershed. To fully characterize...

Introduced pathogens causing emerging infectious diseases (EIDs) are serious contemporary threats to animal, plant, and ecosystem health. The invasive fungus, Pseudogymnoascus destructans, has established populations of European origin in North America, resulting in mass mortality of several hibernating bat species. Extensive monitoring for this pathogen exists in Europe and North America,...

No abstract available. ...

This document provides guidelines for assessing exposure to future coastal flooding during extreme coastal water level events – whether these are due to tides, surge, wave run-up, or, more likely, a combination of the three. These guidelines provide information about the current and future magnitude of extreme coastal water levels...

Local and global measurements of parasite prevalence and abundance are critical for understanding the dynamics that underlie the diversity, distribution, and evolution of infectious diseases. Here, we present a data set of gut helminths found in (1) raccoons throughout their range, based on primary literature from 1925–2017 and (2) raccoons...

Surveys of environmental DNA (eDNA) have become an important and multifaceted tool for monitoring and identifying distributions and occupancy of aquatic species. This tool is attractive because it is powerful, easy to apply, and provides an alternative to traditional field survey methods. However, validating eDNA survey...

Molecular biological techniques have revolutionized the field of geomicrobiology by providing researchers with robust techniques for identifying microorganisms and characterizing microbial communities in a wide variety of environments. These techniques have freed researchers from the constraints of classical culture-based microbiology and allowed the discovery of previously unknown phylogenetic diversity of...

Agricultural water quality projects in two distinct topographic regions in Wisconsin collected 5 to 10 yr of continuous stream discharge, suspended sediment (SS), total P (TP), and total dissolved P (TDP) in four watersheds (2100–5000 ha) from 2006 to 2016. Previous agricultural nonpoint SS and TP reduction efforts in two...

Dune erosion is an important aspect to consider when assessing coastal flood risk, as dune elevation loss makes the protected areas more susceptible to flooding. However, most advanced dune erosion numerical models are computationally expensive, which hinders their application in early-warning systems. Based on a combination of probabilistic and process-based...

No abstract available...

The 1994 Northridge earthquake generated world-record ground motions. At the time, the horizontal peak ground acceleration of 1.8 g measured by a seismometer in Tarzana was the largest ever. The same is true of the peak ground velocity of 148 cm/s measured in Granada Hills. Both measurements were within approximately 15 km...

Habitat use, diet, prey availability, and foraging ecology of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus, Vespertilionidae), was examined in the east Maui region inclusive of the Waihou Mitigation Area, Pu‘u Makua Restoration Area and the wind energy facility operated by Auwahi Wind Energy, LLC. The study was conducted...