and dismissing their annual operation as a minor maintenance 

 problem. As a measure of the relationship between initial cost 

 and annual operating costs, an example may be cited. A plan 

 has been prepared for the installation ;.nd operation of 15 ad- 

 ditional weirs and traps in streams tributary to Lakes Huron and 

 Michigan (Fig,l). Ten of these structures are permanent- type; 

 the balance are of the portable-type. The purpose of these 

 installations is two-fold: first, to provide much needed ad- 

 ditional sites for experimentation with ether techniques of con- 

 trol; second, to extend the active control program throughout 

 the United States waters of Lake Huron and into Lake Michigan, 

 This plan, requiring the organization of two additional con- 

 trol zones in Lake Huron and one in northern Lake Michigan, 

 effects complete control of the lamprey in the United States 

 waters of Lake Huron and places two pilot structures in the 

 first organized control unit in Lake Michigan (see ^ig.i, 

 Zones H-2, H-3, and M-l) . 



These 1% structures, predominatly of the permanent -type, 

 will cost an estimated $165,882.00 to install. By careful 

 planning for the best utilization of personnel and equip- 

 ment, it has been computed that operating costs can be held 

 to about $76,969.00 annually. This ratio of initial cost to 

 annual operating expenses can be considered typical of that 

 which wi 11 be met in almost any area of the Great Lakes in 

 initiating a program centered exclusively around mechanical 

 control measures. 



u7 



