Underdrain Tube Wall, Perforation Design and OBPA to Minimize Bio-Chemical Clogging
Bio-chemical clogging of underdrains has been most frequently associated with iron deposits (ochre). The underlying sticking agents have been a variety of bacteria and their exudates commonly...

Bulk Stomatal Resistance in Operational Estimates of Evapotranspiration
General relationships for estimating canopy or bulk stomatal resistance and aerodynamic resistances of grass and alfalfa reference crops for use in the Penman-J.L. Monteith equation are...

Alternative Dispute Resolution in Water Resources Management
In recent years a variety of techniques have been advocated to resolve natural resource conflicts. These approaches have collectively been termed 'Alternative Dispute Resolution'...

Stable Channels with Loose Boundary
Recently, G. Parker suggested that the lateral transport of downstream momentum due to Reynolds stresses should be included in the momentum balance used to calculate the boundary shear...

Geotechnical and Hydraulic Stability Numbers for Channel Rehabilitation: Part II, Application
Stability numbers for bank stability (Ng) and bed stability (Nh) have been developed. Optimum placement of...

Near-Bed Sediment Concentration in Non-Uniform Flows Over Gravel Beds
The calculation of near-bed sediment concentration is formulated in terms of equations governing the dispersion of heavy particles in non-uniform turbulent shear flows over stable gravel...

Analytical and Numerical Modeling at High Sediment Concentrations
Methods for classifying sediment-water mixtures according to material concentration and rheologic properties are discussed. Results from laboratory and field measurements show that bed...

Entrainment of Bed Sediment by Density Underflows
The erosion caused by a density-driven underflow has been studied experimentally. The observations indicate that a strong density current can entrain substantial amounts of bed sediment....

Ultimate Sediment Concentration
The sediment rating curve is used to relate sediment discharge to water discharge, under steady equilibrium flow conditions. The slope of the sediment rating curve is a measure of the...

Effectiveness of Spur Dike Notching
The most widely used technique of ameliorating the environmental effects of river-training works has been to construct notches in spur dikes (or to allow notches to remain in damaged dikes)...

Snow-Melt Triggered Debris Flows Affecting Utah's Megalopolis
During the abnormally wet years of 1983 and 1984, debris flows were triggered late in spring on the west flank of the Wasatch Mountains and elsewhere in Central Utah. These debris flows...

The USDA Water Erosion Prediction Project
New generation water erosion prediction technology is being developed by the USDA Water Erosion Prediction Project (WEPP). The new technology is expected to replace the Universal Soil...

Analysis of Onsite Measurements of Scour at Piers
Existing onsite measurements of local scour at bridge piers were assembled and analyzed to obtain an equation that predicts the expected maximum depth of local scour at a bridge pier....

Scour Downstream of the Straight Drop Spillway
Tests made to determine the effect of high tailwater and long duration flows on scour downstream of the straight drop spillway stilling basin are presented in this paper. Results are presented...

Local Scour Downstream of a Tunnel Outlet Structure
The local scour downstream of two different types of outlet structures is studied in laboratory experiments with an alluvial sediment. The outlet structure terminates a hydraulic model...

Prediction of Scour Depth Under Armoring Conditions
A simple procedure is proposed to compute scour depth on an alluvial bed having graded materials under flow conditions which produce armor layer at the bed surface. The procedure is based...

A Model of Flow in Regulated Open Channel Networks
A model (NETWORK) is presented for the simulation of unsteady flow in regulated open channel networks. The operation of hydraulic structures, such as gates and weirs, are simulated as...

Channel Response to SCS Type-C Grade-Control Structures on Burney Branch, Mississippi
Five SCS Type-C grade-control structures were installed in Burney Branch in 1980 to remove 59.4 feet (18.1 m) of grade. The performance of the structures was evaluated in 1984 after they...

The Effects of Sediment Transportation Changes on Aquatic Habitat
Sediments are a natural part of the riverine and estuarine environment. However, if the sediment load changes or bed sediment type occur, direct and sometimes detrimental and sometimes...

Analysis of Spillway Failures by Uplift Pressure
Results of a model study to evaluate the development of uplift pressures beneath concrete chutes are presented. Two spillway failures are described to support the study results. Common...

 

 

 

 

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