Buffer zones are similarly important to separate the active channel 

 from material sites located on the outside of meanders. A breach occurring 

 in this situation would lengthen the meander. This breach probably would be 

 a temporary event during high flow periods and the river would maintain its 

 main flow through the active channel during lower water levels because of 

 the shorter downval ley distance. Periodic and aggravated damage to the area 

 between the material site and the active channel and perhaps the creation of 

 a backwater area in the material site, would occur from an outside meander 

 breach. 



It is obvious that the closer a material site is to the active channel 

 the greater the probability of a permanent breach occurring in a short time. 



Placement of a material site either on the inside or outside of a 

 meander has no effect on water quality, regardless of the distance sep- 

 arating the site from the channel. However, if water is ponded the water in 

 the pit would differ from that in the channel, as described in the section 

 on pits. Changes in water quality could result if a breach occurs. These 

 also are discussed in the section on pits. 



Change will not occur to aquatic biota when material sites are located 

 away from the active channel. However, if high flow conditions reach a 

 material site, and cause either temporary or permanent ponding, fish could 

 become trapped in the site when the water recedes. Effects similar to those 

 described for connected pits could occur where the buffer is breached and a 

 pit site becomes connected to the active channel. 



In general, locating material sites back from the active channel will 

 necessarily entail destruction of vegetative habitat. This will result in 

 local ized loss of sma I I mammals and displacement of birds and larger mam- 

 mals. If the area is scraped and does not become flooded during high water 

 the site eventually will return to the pr ed i sturbance condition through 

 processes of primary and secondary plant succession. The length of time 

 required will depend on the regional characteristics. If the site is flooded 



373 



