Beginning in 2012 Friends of the Kaw received a grant from the Water Protection Network to work with the Kansas State University Rivers Systems Research Group to monitor and study dredge operations on the river. While studying the river our worst fears are being confirmed, as significant river bed degradation appears to be present at our dredge hole study sites. In year one of the project the active dredge hole east of Topeka in the Kansas River was surveyed on three separate occasions.
- The first survey found that the dredge hole depth was approximately 33 feet deeper than the nearby channel of the Kansas River (figure on left). The average river water depth at the time of this survey was only about three feet.
- After a dry winter with no flows capable of transporting large quantities of sediment, the dredge site was resurveyed again (figure to the right). This second survey revealed a substantially larger dredge hole. It appeared that the dredging operation had extended to mine directly into a large sand bar. Although the dredge hole expanded in area, the maximum depth remained the same.
- The most recent survey data from the third survey is still being processed, but initial results show that the summer high flows resulted in about six feet of sediment accumulating in the bottom of the dredge hole.
With information from this study a computer model can be developed to measure the effect of dredging on river bed stability upstream and downstream. More data needs to be collected to better understand the potential negative impacts that sand dredging may have on river bed degradation along the Kansas River.