Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/thsj19Determining suspended sediment loads from turbidity records / La détermination des charges en suspension des rapports sur la turbidité Abstract, The Pennsylvania Department of Transportation and the US Geological Survey are cooperating in several field studies to evaluate sediment control measures used during highway construction. Among the parameters being monitored are suspended sediment concentration and turbidity. Sediment loads are calculated from suspended sediment and water discharge data, but some sediment loads must be determined indirectly because it is virtually impossible to obtain sufficient suspended sediment samples to define all runoff conditions adequately. Sediment discharge-water discharge correlation curves have proved unreliable for streams affected by highway construction, so an alternative method using the turbidity record was developed during these studies.The field data reveal a good correlation between daily mean discharge-weighted turbidity and daily mean discharge-weighted suspended sediment concentration. Turbidity is monitored and recorded continuously, and the daily mean discharge-weighted turbidity is calculated from the turbidity and water discharge data. During periods when there are insufficient suspended sediment data, the daily mean discharge-weighted suspended sediment concentration is determined from the turbidity-sediment correlation and used with the daily mean water discharge to calculate a daily sediment load.This method of determining sediment loads from the turbidity record suggests a possiblity for computation of sediment loads by computer. Instrumentation now in use for recording water quality parameters on digital punch tape could be used to record the output from a turbidimeter. Then, for streams having a good correlation between suspended sediment concentration and turbidity, simultaneous water discharge and turbidity data could be used to determine sediment loads by computer.
La détermination des charges en suspension des rapports sur la turbiditéRésumé, 'The Pennsylvania Department of Transportation' et 'the US Geological Survey' sont en coopération pour piusiers essais sur le terrain pour évaluer les mesures pour îe contrôle des sédi-ments pendant la construction des routes. Parmi les paramètres qu'on étudie de près se trouvent la concentration de matière en suspension et la turbidité. Les charges en suspension sont calculées des données disponibles de matière en suspension et d'écoulement d'eau. Cependant on doit déter-miner de façon indirecte quelques charges en suspension parce ce qu'il est à peu près impossible d'obtenir assez d'échantillons de matière en suspension pour pouvoir bien définir toutes les conditions d'écoulement. Les courbes de corrélation débit solide-débit d'eau se sont montrées peu fidèles pour des cours d'eau influencés par la construction des routes, donc on a développé une méthode alternative en utilisant le rapport ...