from the location of the typical zones of erosion that the buffer width should 

 generally be greater on the outsides of meanders and the upstream side of the 

 insides of meanders. 



As an example, consider the hypothetical river in Figure A-9 with a 

 regular meander pattern. A material site is proposed on an inside meander of a 

 small river, for which a buffer design life of 25 years is desired. 



Figure A-9. Schematic of a river with a regular 

 meander pattern and a proposed location for a 

 mater ia I site. 



The buffer surrounding the material site is separated into zones A and B 

 because they are zones of different expected erosion rates. Historical erosion 

 rates for zone A were 90 m between 1948 and 1978, or an average rate of 5 m 

 per year. In zone B, 270 m of deposition has taken place during the same 

 period. Starting with zone B, the bank opposite this zone should be inves- 

 tigated for any abnormality such as near-surface bedrock, which may stop the 



94 



