Rivers around the world are being regulated by dams to accommodate the needs of a rapidly growing global population. These regulatory efforts usually oppose the natural tendency of rivers to flood, move sediment, and migrate. Although an economic benefit, river regulation has come at unforeseen and unevaluated cumulative ecological costs. Historic and contemporary approaches to remedy environme...

The lowermost Mississippi River, defined herein as the river segment downstream of the Old River Control Structure and hydrodynamically influenced by the Gulf of Mexico, extends for approximately 500 km. This segment includes a bedrock (or more precisely, mixed bedrock-alluvial) reach that is bounded by an upstream alluvial-bedrock transition and a downstream bedrock-alluvial transition. Here w...

In this study, the distribution of channel-bed sediment facies in the lowermost Mississippi River is analysed using multibeam data, complemented by sidescan sonar and compressed high-intensity radar pulse seismic data, as well as grab and core samples of bed material. The channel bed is composed of a discontinuous layer of alluvial sediment and a relict substratum that is exposed on the channel...

The Tamarack State Wildlife Area in eastern Colorado is being investigated as a possible managed recharge project to redirect flows in the South Platte River for water quantity management. Two primary surface water/groundwater interactions exist at Tamarack: (1) between the South Platte River and alluvial aquifer and (2) between backwater sloughs, or secondary river channels, and the alluvial a...

Harris Wash, a tributary of the Escalante River in south-central Utah, has two wellpreserved alluvial terraces of compound origin in its lower reaches. The alluvial stratigraphy of the deposits that compose these terraces reflects the complex processes of canyon filling and erosion. The compound terraces were formed by general aggradation of the valley, by deposition from large floods that also...

Alluvial aquifers in mountainous regions cover typically a limited area. Their contribution to catchment storage and outflow is rarely isolated; alluvial groundwater discharge under gauging stations is generally assumed negligible; and hydrological models tend to lump alluvial storage with other units. The role of alluvial aquifers remains therefore unclear: can they contribute significantly to...

An alluvial aquifer can be described as a groundwater system, generally unconfined, that is hosted in laterally discontinuous layers of gravel, sand, silt and clay, deposited by a river in a river channel, banks or flood plain. In semi-arid regions, streams that are associated with alluvial aquifers tend to vary from discharge water bodies in the dry season, to recharge water bodies during cert...

Based on analysis of groundwater hydrochemical and isotopic indicators, this article aims to identify the groundwater flow systems in the Yangwu River alluvial fan, in the Xinzhou Basin, China. Groundwater delta(2)H and delta(18)O values indicate that the origin of groundwater is mainly from precipitation, with local evaporative influence. d-excess values lower than 10% in most groundwaters sug...

[1] A viscoelastic model is developed to simulate the groundwater level changes in the Cho-Shui River alluvial fan in Taiwan after the Chi-Chi earthquake. An analytical solution is derived with the assumption that no leakage occurred in confined aquifers during the coseismic period. The solution is used to analyze the data collected from a high-density network of hydrologic monitoring wells in ...

The diversion of natural river courses and subsequent filling by alluvial deposits or anthropic intervention has been hidden by urban development in the majority of the cities. The research we conducted involved monitoring the evolution of a river course and reconnaissance of the original morphology of the fluvial systems. Our research was applied to the section of the River Beiro that flows th...