The potential effects of removing gravel from sinuous ctiannel rivers 

 are increased because of these limitations. If point bars are scraped too 

 deeply, or if incised banks and the adjacent floodplains are disturbed, the 

 potential for decreasing channel stability is greatly enhanced. The initial 

 disturbance from site clearing, and the changes resulting from a poorly 

 located and operated site, will have multiple effects. 



The decreased channel stability and tendency for braiding will affect 

 both benthos and fish by altering aquatic habitats. Benthic communities 

 adapted to riffles, fine sediment bottoms, and a relatively unstable bottom, 

 will become established. Loss of bank cover and potentially reduced current 

 in the disturbed site will affect fish distribution and perhaps species 

 composition. In addition, reducing water depth and velocity could change 

 water temperatures and affect the level of dissolved oxygen. Fish could 

 become trapped in the disturbed site when water recedes following high 

 f I ows. 



Terrestrial vegetated habitat will be destroyed when the floodplain 

 adjacent to the channel is used as a material site. This destruction of 

 vegetation will cause either elimination or displacement of terrestrial 

 fauna. If the stream banks are affected the decreased hydraulic stability in 

 the area could reduce the potential for re-establishment of vegetative com- 

 munities, thus creating a long-term rehabilitation problem. 



Gravel removal from a sinuous river will have effects on the scenic 

 quality similar to those discussed for a meandering system. The degree of 

 effect is fully dependent on the diversity of landforms in the area of the 

 site and the amount of disturbance. Single channel river systems are scen- 

 ically more sensitive than multiple channel systems particularly those 

 single channel rivers located in areas with low growing vegetation, such as 

 on the North Slope. 



In summary, the amount of environmental change that can be anticipated 

 in a sinuous river system is largely dependent on the location of the ma- 

 terial site and the methods of operation. Anticipated effects are similar to 



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