DATA 

 FISHWAY AT ESSEX COMPANY DAM, LAWRENCE, MASS. 



(above mean sea level) 



(above mean sea level) 

 (above mean sea level) 

 (above mean sea level) 



8 ft. 



sloped. 



- 2 in. 



Thickness of Weir 



Maximum Water Velocity over Weir. 



Water Volume 



Entrance 



width of notch top 

 " » " bottom 



depth of notch 



floor - - - - 



bevel (downstream 

 edges ) 

 1 ft. 



5.6 ft/sec. 



Approx. 10 cubic feet per second, 

 h ft. wide, rounded, weir flooded 

 when shad enter, no "jump" at 

 entrance. 



ft. 

 ft. 

 ft. 



Tailwater Velocity through Entrance 

 (above mean sea level) (ft/sec.) 



(Probable minimum water level 



when shad enter).. 11,0 



n.5 



12.5 



(Probable maximum water 13.5 



level when shad enter)... lU.5 



2.6 

 1.7 

 1.0 

 0,6 

 0.3 



Estimated Number of Shad ascending annually ..... 1,500 to 3*000. 



Remarks s 



Flow in fishway is characterized by low velocities 

 and a low degree of turbulence. 



