CONTENTS 



Page 



History of the Denil-type ladder , 1 



Design developments of the Denil-type 'ladder 3 



General design features of the Denil-type ladder at 



Dryden Dam 5 



General design f eatures of the Pool-type ladder at 



Dryden Dam. ... - 8 



The exp erL raent .^ 10 



Discussion 13 



Summary and conclusions l5 



ILLUSTRATIONS 

 Figure Page 



1. Perspective of Denil-type fish ladder with 



single-plane baffles 2 



2. Pictorial representation of flow conditions in 



Denil-tj'pe fish ladder, with direction of flow at the 

 various depths shown by position of thread banderoles. 

 {Redrawn from Furuskog 19Ui) 1; 



3. Arrangment of structures at Dryden Dam. 6 



ii. Pool-type fish ladder in 19^8 prior to construction of 



the Denil-type ladder 7 



5. The Denil and pool-type fish ladders in operation in 



19U9. 7 



6. General design of Denil-type fish ladder at Dryden Dam.... 9 



