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Increasing the power generation and reducing the sediment deposition in a reservoir are two contradictory and incommensurable objectives. Hence, these two operational objectives rarely are considered simultaneously in reservoir optimization. This study proposes a method to balance sediment desilting and power generation in reservoirs, and to study their quantitative relationship. First, a formula to calculate the suspended sediment transport rate for reservoirs was established. Second, based on that formula, a multiobjective model was built that considers simultaneously, the sediment transporting efficiency and the power generation efficiency. The nondominated sorting genetic algorithm (NSGA-II) along with Pareto optimality was used to find the Pareto front of the model. The proposed method was applied to the Three Gorges project in China. The research results not only provide the Pareto front of the reservoir operation scheme, but also imply that the maximum annual sediment runoff was improved by 6% at the expense of 9% of the annual power generation. [ABSTRACT FROM AUTHOR]

Rural nonpoint sources of water pollution are particularly difficult to control, with relatively little progress having been made compared to point sources. Management choices are difficult because of large uncertainties in both the monitoring of nonpoint pollution and the effectiveness of various actions to reduce that pollution. This study includes a proposed framework for selecting the optimal combination of research, monitoring, and management actions. The approach combines Bayesian inference and multiobjective linear programming to explicitly represent uncertainty in the effectiveness and cost of controls and to quantify the value of reducing uncertainty through research and monitoring. The authors illustrate the framework using the problem of reducing turbidity from rural sediment sources in the Minnesota River basin. The results show that a combination of research methods in different subbasins usually yields the most valuable information and is predicted to result in benefits via reduced cost and increased effectiveness of sediment reduction. [ABSTRACT FROM AUTHOR]

A strategy for developing sediment transport information for storm water planning and management is described. The strategy links location-based and intensity-based development scenarios with potential water quality impacts to a stream system and at a watershed outlet and (1) is based on sediment transport calculations; (2) develops information that supports community decision making; and (3) is consistent with the Environmental Protection Agency (EPA) Phase II storm water requirements and other guidance on watershed management. The strategy is an effort to incorporate the impact of site-specific watershed characteristics into storm water ordinances. This effort was undertaken to provide a rational means for a community to differentiate the sediment contributions from alternative scenarios at alternative locations. One of the options available with differentiation information is the ability to negotiate and approve pollutant “trades” between different development practices in different locations such that water quality standards are maintained throughout the trading area. The Agricultural Non-Point Source (AGNPS) pollutant modeling system was used in the community of Ashland, Mo. to provide an example of the methodology. [ABSTRACT FROM AUTHOR]

We present a computational approach for identifying the significance of uncertainty in assessing the consequences of sediment and nutrient transport in a section of the Chattahoochee River south of Lake Lanier, as it passes through Atlanta, Georgia. Specifically, our analysis aims at identifying the key control and management actions, and the key scientific uncertainties about the fluvial system, that govern the attainment of a set of water quality objectives for the downstream boundary of the study area. To this end, we present a computational framework that integrates a recently developed sediment-nutrient dynamics model with a Monte Carlo-based methodology for model uncertainty evaluation. Our results suggest that, in general, reliable execution of controls and management actions is more crucial to meeting the target values for flow, sediment, and phosphorus concentration, than the scientific uncertainties associated with fluvial processes within the river channel. We also discuss the potential utility of our framework for accommodating the various science- and policy-derived uncertainties in the total maximum daily load process. [ABSTRACT FROM AUTHOR]

Studies the methods of sediment movement and their significance in maintaining the drainage system. Types of sediments; Description of the sediment movement; Materials and equipment used to address the sediment movement.

Presents a study which examined the effects of vegetative practices on suspended sediment discharge from ponderosa pine forests and pinon-juniper woodlands in Arizona. Details on the study area; Procedures; Conclusions.

Discusses an article on predicting sediment yield in storm-water runoff from urban areas. Problems with the approach taken by the authors in predicting sediment yield; Limitations of the study; Results of simulations.