Kiowa County Public Library District

This study is a continuation of the work to determine the point of incipient failure and other hydraulic characteristics of riprap for providing criteria for design of stable ripraps in flood control channels. Two sizes riprap materials were tested. One material had a d = 1.0 in. and the other had a d₅₀ = 2.0 in. Both riprap sizes had the ETL 1110-2-120 gradation recommended by WES.

Fluvial Hazard Zone mapping represents a significant and necessary step forward in identifying and addressing hazards posed by flood events. Flood hazard reduction, in the long-term, will primarily be measured by our ability to solve problems at the watershed and river corridor scale, and secondarily, by how we resolve conflicts at individual sites. From a physical standpoint, this means recognizing that rivers transport and deposit water and sediment...

It has been suggested in a number of recent reports that the decline in native fish populations in the Colorado River system is due primarily to habitat loss and environmental changes associated with the construction of reservoirs and water diversions. However until we began examining this issue no one had actually determined the significance of channel change on the Colorado River nor had the link between flow regulation and channel change been well...

Surveys of the Colorado River near Grand Junction, Colorado show that populations of Colorado squawfish (Ptychocheilus lucius) and razorback sucker (Xyrauchen texanus) are small and continue to decline. A potentially important factor in their decline is a reduction in the amount of available habitat. The fish are most commonly found in habitats of complex channel which may be affected by bank stabilizing activities and regulation of the river flow....

This report summarizes recent observations and field measurements of channel change in selected reaches of the Colorado River near Grand Junction Colorado This work was undertaken to assess effects of recent high flows on sites that have been monitored as part of on-going fish habitat studies.