Scott A Wright (Former Employee)

Sediment supply is important to the health of the Sacramento-San Joaquin River Delta and San Francisco Bay (Bay-Delta) ecosystem. Sediment eroded from upland source areas in the Sacramento and San Joaquin watersheds is transported through the rivers to the Bay-Delta where it is deposited in mudflats and tidal wetlands, which in turn helps protect against the effects of sea-level rise. Sediment...

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

The spawning of adult white sturgeon ( Acipenser transmontanus ) in the lower San Joaquin River was documented recently by the United States Fish and Wildlife Service (USFWS) (Gruber and others, 2012; Jackson and Eenennaam, 2013). Streamflow on the San Joaquin River has been modified by State and Federal water project operations, and there are a variety of questions regarding the effects on fish...

The purpose of the proposed work is to collect data that will support the development, calibration, and validation of numerical models of sediment transport and turbidity in the Sacramento-San Joaquin Delta.

The National Park Service (NPS) and USGS jointly will investigate impacts to the Merced River due to infrastructure and historic channel widening in east Yosemite Valley with a goal of constructing river management alternatives. Past management actions, such as gravel mining, channel riprap, and the construction of bridges that do not accommodate flood flows, have had long-lasting impacts to the...

The Fena Valley Reservoir, located in southern Guam, is the primary source of water for the United States Naval Base Guam and nearby village residents. At full capacity, the reservoir surface area extends approximately 0.30 mi 2 , and drains a watershed area of about 5.88 mi 2 . After reservoir construction, periodic bathymetric surveys, coupled with sedimentation models, can be used to produce...

Traditional methods for measuring coarse bedload sediment transport by discrete physical sampling tend to be labor intensive and expensive ( Gray and others, 2010 ). As such, bedload samples often are collected too infrequently to capture the temporal variability inherent in transport rates, which can vary significantly, sometimes by a factor of ten or more, over time periods of several minutes to...

Over time, the flow of water into the San Antonio Reservoir has caused the build-up of sediment, decreasing storage capacity. Since water storage is a crucial issue in California, up-to-date information on the reservoir is needed. To accomplish this, the San Francisco Public Utilities Commission approached the USGS California Water Science Center to conduct a bathymetric (depth) survey and other...

The Rim Fire has burned over 400 square miles of the Tuolumne River and Merced River watersheds in central California and is now the 3rd largest wildfire in state history. The burn area is largely on the Tuolumne between Hetch Hetchy Reservoir and Don Pedro Reservoir, both of which serve as critical sources of drinking water and irrigation water to San Francisco Bay area and Central Valley...

Accurate river-sediment data is fundamental to planning and managing river restoration efforts on the Trinity River, and throughout the world’s waterways. The USGS has developed a “hydrophone” that enables scientists to listen to sediment particles as they move along the riverbed in order to inexpensively and reliably record near-continuous sediment-bedload-transport data. For this study...

This project team developed a Web-hosted application (that can also be used on mobile platforms) for automatic analysis of images of sediment for grain-size distribution, using the “Digital Grain Size” (DGS) algorithm of Buscombe (2013) (“DGS-Online,” 2015). This is a free, browser-based application for accurately estimating the grain-size distribution of sediment in digital images without any ma