Four material sites on meandering systems were studied on this project 

 (Table I). Two were dug as pits and two were scraped. 



Pit Sites. The material sites at Prospect Creek and West Fork Tolovana 

 River were dug in abandoned channels. In neither case was there a change in 

 the lateral stability of the active channel. There was loss of terrestrial 

 vegetation and associated fauna because the material sites were located back 

 from the active channels. Aquatic fauna in the active channel apparently did 

 not change. Change, if any, was due to the presence of an adjacent flood- 

 ed pit. Similarly, water quality did not change in the active river channels 

 but, as expected, water quality in the pit was different from that in the 

 active channel. These differences and changes are discussed in the section 

 on Type of Gravel Removal because they were not unique to meandering sys- 

 t ems . 



Formation of a permanently flooded pit within a floodplain, that other- 

 wise contains few ponds or lakes, changes the appearance of the area by in- 

 creasing the diversity of physical features. These pits are quite visible 

 when seen from the air or from a high terrestrial vantage point. Ta I I vege- 

 tation in the areas of these two material sites contributed greatly to 

 blocking view of the sites. 



Many meandering river floodplains contain a multitude of oxbow lakes 

 that are formed by channel cutoffs. In these cases, a pit could blend easily 

 into the natural landscape, thus greatly reducing the visual effect of 

 gravel removal operations. However, most pits are dug with angular perim- 

 eters which create a visual contrast in the floodplain. This contrast is a 

 generic problem and will be discussed further under Type of Gravel Removal. 



Scraped Sites. The material sites on Aufeis Creek and Skeetercake Creek 

 were scraped. The environmental changes were quite different at the two 

 sites resulting principally from differences in their locations relative to 

 the channel (Table 4-0). The gravel at Aufeis Creek was scraped from across 

 the entire channel, which changed the channel from a single to a braided 

 configuration. The short-term influence was so severe that surface flow was 



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