Sediment Loads of Illinois Streams and Rivers

Many river projects require knowledge of the sediment load transported by the river. Suspended sediment load data for 63 locations on Illinois streams and lake sedimentation data from 24 lakes were compiled along with geomorphic information on each location. Station records were investigated, and annual and period-of-record regression equations are given for each station. Short record length (average of 2.25 years) limits the value of individual station data. Data from rivers in other midwestern states were investigated for longer-term variability. Average annual sediment loads were computed, using the period-of-record regression equation and the flow duration table for each station. These annual loads and the annual loads from the lake sedimentation studies were combined with watershed boundaries and physiographic and geomorphic data to delineate 11 Sediment Yield Areas (SYAs) within the state. Linear and multiple regression equations are presented for each SYA, and example problems outline use of the equations. Separate analyses are presented for stations on the Illinois and Mississippi Rivers.publishedpeer reviewedOpe