Reduced streamflow via flow diversion has the potential to limit the sediment-transport capacity of downstream channels and lead to accumulation of fine sediments and habitat degradation. To investigate, we examined the effects of variable levels of flow diversion on fine-sediment deposition, hydraulic conditions and geomorphic alteration. Our study consisted of a detailed field analysis pairin...

The CANWET (Canadian ArcView Nutrient and Water Evaluation Tool) and HSPF (Hydrologic Simulation Program – FORTRAN) models were applied to Upper Canagagigue Creek watershed of the Grand River basin in southern Ontario, Canada, for hydrology and sediment evaluations. Both the models have similarity in structure where CANWET is simpler, both in algorithms and use, than HSPF. The outputs of both t...

Flowthrough reactor flasks are described that allow continuous low-level nutrient input to mixed anoxic sediments without dilution of the sediment. The flasks were tested by simulating sulfate inputs into sediments collected from a freshwater eutrophic lake. After an initial 2-day adaptation within the reactor system, rates of methane production and sulfate consumption were constant for the dur...

We investigate the use of the short-lived fallout radionuclide beryllium-7 ( Be; t1/2 = 53·4 days) as a tracer of medium and coarse sand (0·25–2 mm), which transitions between transport in suspension and as bed load, and evaluate the effects of impoundment on seasonal and spatial variations in bed sedimentation. We measure Be activities in approximately monthly samples from point bar and stream...

abstract rockfill dams are a type of hydraulic control structures used to protect river bed in cases where a considerable reservoir volume is available behind these structures; it could mitigate the floods and provide a gradual depletion of incoming volume of water so that the discharge passing downstream is decreased. one of the main issues on utilizing rockfill dams is to keep its permeabilit...

this paper describes the problem of sedimentation in reservoirs,in general, and offers an estimate of the annual rate of storage loss and the useful life of sefidrud reservoir in iran,in particular. the life of sefidrud reservoir was predicted to exceed 100 years in the design, based on insufficient data. regular daily measurements of sediment discharge of the river, taken years later, however,...

We compute rates of sediment removal from the Columbia River, USA plume near field using a control volume technique. By using data from repeated transect passes along the plume axis, we account for variations in plume width, depth, and velocity, and we construct a framework for determining the dominant terms in the complete sediment balance. The contribution due to turbulent sediment flux is es...

[1] Bedrock erosion in mountain river channels ultimately sets the erosion rate of the surrounding hillslopes and the rate of sediment supply to the channels. The supply of coarse bed sediment acts as a dampening effect on further erosion by depositing an alluvial cover that temporarily obscures the bedrock. For landscapes where the residence time of the alluvial bed cover is comparable to the ...

Stratigraphic inverse modeling using the SEDPAK stratigraphic simulator established the size of the physical parameters that together controlled the development of the stratal patterns in the late Tertiary Ulleung Basin, East (Japan) Sea. The modeling results provided a quantitative geohistory of the basin. This included the dimension of variations in rates of tectonic subsidence (or uplift) an...