4. Specific Guidelines for Dredged Sites 



a. Active channels scheduled for winter dredging should be evaluated 

 for the presence of flowing water in and downstream from the 

 site; if water is found, the site should not be mined 



b. Depth of excavation in an active channel should be limited by 

 the width of the low summer flow channel minus the low-flow buf- 

 fer; the side slopes should be designed to remain stable during 

 5-year flood flows 



c. The length of excavation in a pool of the active main channel 

 should not exceed the length of the pool. If a riffle is to 



be mined, the length of excavation should not exceed the average 

 length of the pools within 5 km up and downstream of the site. 



d. The bed slopes at the upstream and downstream ends of the active 

 channel excavation should be designed to remain stable during 

 5-year flood flows to minimize the potential for degradation 



74 



VI. SITE OPERATION 



