Scour Processes Observed in Field Data
River channels scour and aggrade due to complex, interrelated natural processes that are dynamic over space and time. Channel scour is particularly difficult to predict for bridge crossings,...
Entrainment of Eggs and Larval Fish into Propeller Jets
Because larval fish have limited mobility and eggs have no mobility, both are susceptible to entrainment into the propeller jets of passing vessels. Entrainment subjects eggs and larvae,...
Field Verification of Dem-Derived Watershed Response
Rainfall-runoff data from an NAEW Experimental Watershed are used to test the feasibility of deriving the watershed response from the digital elevation model of the watershed. Using Clark's...
Assessment and Implications of Local Channel Instability on the Prediction of Bridge Scour
Current assessments of the potential for scour at existing and new bridges do not include the effects of local channel instability on predicted bridge scour estimates. Local channel instability...
Use of Geomorphic Data for Assessing Stream Stability at Bridge Structures
The authors recently completed a statewide bridge scour evaluation for the Nevada Department of Transportation, which included evaluation of the geomorphic processes of bank erosion and...
Industry Standards for Erosion Control Products�Future Tools for Civil Engineers
In 1990, the International Erosion Control Association (IECA) formed a Cooperative Standards Program (CSP), directed by the IECA Committee on Standards. The purpose of the CSP is to develop...
Channel Restoration of Incising, Mixed Grain Size Streams: Lessons Learned
Aquatic habitat restoration in incising sand and gravel bed streams disturbed by channelization and other human interventions has received little study. These channel systems are characterized...
3D Flow Structures?From Laboratory to Field Applications
One laboratory experiment and one field application have been modeled. For each one different sources of errors in the model results could be detected. It may be concluded that the applicability...
Verification of a 3D Flow Model Using Laboratory Data
The ASCE Task Sub-Committee on 3D Free Surface Flow Model Veri fications has been developing test cases and/or procedures for both computational model developers and users over the past...
Developing a Rating Table for the Central Diversion Dam Radial Gates
The Central Nebraska Public Power and Irrigation District uses radial gates for flow control throughout its system. The rating tables for five radial gates on a diversion dam are in error,...
Discharge Characteristics of Overshot Gates
Overshot gates are becoming increasingly popular for controlling water levels in open channels because of the ability of the gates to handle flow surges with limited depth changes. While...
The Effects of Water Surface Profiles on Manning's Roughness Coefficient
The Manning Equation has wide application in engineering practice. Nonetheless, certain aspects of it are still not widely understood. Often, engineers deduce the value of Manning's...
A New Technique for Measuring Vegetation Density
Detennination of the discharge capacity of a vegetated channel or floodplain requires a reasonable estimate of a flow resistance coefficient; such as Manning'
Contraction Scour at Bridges: Analytic Model for Coarse-Bed Channels
Contraction scour at bridges spanning coarse-bed channels is evaluated based on mass conservation of both water and transported sediment between a reference channel section near the crossing...
Capillary Pressure-Saturation Relationships in Fracture
Understanding and quantifying unsaturated flow through fractures in rocky slope is important for design and construction of drainage system in large-scale hydraulic engineering. The data...
Comparison of Near-Field Dilutions Derived from In Situ Measurements and Simulated Dilutions at the Sand Island Sewage Outfall Plume, HI
Near-field dilutions of the Sand Island Treatment Plant (SITP) wastewater plume were derived from salinity measurements made at the sewage outfall between Sept. 25?Oct. 1, 1994, a period...
Irrigation of Grain Sorghum on the Delmarva Peninsula
Irrigated grain sorghum experiments were conducted for two years on a Norfolk sandy loam soil. Full irrigation was compared to partial irrigation and no irrigation in a randomized block...
Regional Economic Impacts of a Land Fallowing Program?The Palo Verde Test Land Fallowing Program Case Study
The Metropolitan Water District of Southern California (MWD) and the Palo Verde Irrigation District (PVID) implemented a two-year test land fallowing program (Program) from August 1, 1992...
Laboratory Evaluation of a Conductivity Probe for Scour Monitoring
Laboratory tests were used to evaluate the ability of conductivity sensors to measure streambed elevation. Tests were completed on a 2.1-m probe with a resolution of about 8 cm that was...
Evaluation of Selected Instruments for Monitoring Scour at Bridges in New York
Reliable methods to monitor scour at bridges are needed to ensure public safety and minimize the cost to repair or replace vulnerable bridges. The U.S. Geological Survey, in cooperation...
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