Results obtained with a similar array in Carp Creek were as 

 follows (power applied to array - 110 VAC):6/ 



These devices in Hibbards' and Carp Creeks were tested solely 

 as simple barriers to the upstream movements of lampreys; as such, they 

 functioned effectively and inexpensively with a minimum of installed 

 equipment. 



The use of this simpler electrode array to supplant the more com- 

 plex and expensive multiple-row, suspended electrode systems of the elec- 

 tromechanical weirs and traps appears feasible. Until further investiga- 

 tions have been made, however, such use in electromechanical devices should 

 be restricted to sites where the water is comparatively shallow and where 

 relatively rapid water velocities, at least in excess of 1.5 f.p.s., exist. 

 Observations at Hibbards' Creek where deeper and very sluggish water oc- 

 curred (static to 0,52 f.p.s.) at the electrical barrier site indicated 



6/ Records of voltage gradients were faulty and hence are not given here. 



36 



