Vertical Transport in the Vadose Zone by Fingering
Water containing contaminants may infiltrate through the vadose zone as a series of fingers which result from a hydrodynamic instability initiated at an interface in which a fine textured...
Nitrate and Bromide Transport Through a Vadose Zone in New Jersey
Ongoing field experiments on monitoring transport of Sodium Nitrate and Potassium Bromide in the vadose zone over a shallow groundwater table in the coastal plains of New Jersey are discussed....
Erosion Processes in Upland Areas
After a soil particle is detached and entrained, it will be transported by the surface runoff. However, depending on the eroding and transport capacities of the surface runoff, some of...
The Effect of Grain Size Distribution on the Entrainment of Interstitial Water into Overland Flow
Non-point source pollution from agricultural runoff is an important environmental problem. This experimental study considers the effect of media heterogeneity on the entrainment of interstitial...
Effect of Temperature on Settling of Fine Sediments
Results from settling experiments in an annular flume using kaolinite clay in distilled water are presented. Identical experiments carried out at different temperatures show that as temperature...
Uncertainty of Runoff Volume as a Function of Rainfall and Catchment Characteristics
The expected variability of runoff volume due to the uncertainties in spatial distribution of rainfall and catchment characteristics is quantified. A physically-based mathematical model...
Design and Construction of Soil-Cement Drop Structures
Soil-cement has been used as an effective and economical slope protection material for embankment dams and stream banks. This paper describes the use of soil-cement in the construction...
Scour in Non-Cohesive Beds at Culvert Outlets
An empirical relationship was developed to estimate the depth of scour in non-cohesive material at culvert outlets. The scour depth is expressed as a function of mean particle size of...
Maximum Scour Below Dams Caused by Over-Fall Flow
The scour of sediment below a check dam caused by over-fall flow will lead to the destruction of dams. The formation of the scour hole below the dam will lead to shorten the seepage lines,...
Bed Sediments and Bed Forms of the Lower Mississippi River
Approximately 500 bed material samples were collected from the thalweg of the Lower Mississippi River. At each sample location, a sonic record of the bed was obtained. From the appearance...
Characteristic Deformation of Alternate Bars Due to Low Flow
Experiments on the formation of a small meander-channel at low stage are conducted by supplying a proper discharge on initial bed of alternate bars that have been formed in experimental...
Sediment Concentration Measurements Below Small Headcuts
This study is designed to determine erosion rates downstream from a small headcut. The sediment concentration from a scour hole produced by a plunging jet is measured as a function of...
The Effect of Aeration on Scour
A vertical water jet was used to study the effects of entrained air, tailwater depth, size of bed material, jet diameter, and jet velocity on scour. Small amounts of entrained air were...
The Calculation of Flushing Flows for Gravel and Cobble Bed Rivers
Flushing flows are needed to remove fines and sand from a gravel or cobble bed river. A natural stream will have periodic high flows adequate for flushing of fines and sand, but the hydraulic...
River Sediment Discharge Study?San Diego Region
Procedures and general results are presented of a recent study performed to estimate the average annual sediment delivery (sand sizes and larger) from sources discharging to the southern...
Major Sedimentation Activities in the Soil Conservation Service
The Agricultural Research Service (ARS) and Soil Conservation Service (SCS) are cooperating in the development of tools to improve prediction of the magnitude of erosion processes, the...
Sediment and Aquatic Habitat Associations in River Systems
This paper results from the Task Committee's effort to summarize knowledge linking sediment transport and aquatic ecology. This paper presents one element of this work: the...
Sediment Transport, Hydraulic Retention Devices, and Aquatic Habitat in Sand-Bed Channels
Streams and rivers of all sizes and in all parts of the United States flow on sand-bed channels. Scour, Transport, and deposition of sediments particles are natural processes in these...
Delineation of Ordinary High Water
'Ordinary high water' is used in a court of law to delineate the extent of land ownership of adjacent riparian owners on navigable rivers. The most appropriate...
Sacramento's Proactive Stormwater Permit Program
In January 1990, with the encouragement and assistance of the California Regional Water Quality Control Board-Central Valley Region (Regional Board), the City and County of Sacramento,...
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