34 



BULLETIN 906, U. S. DEPARTMENT OF AGRICULTURE. 



Table 2. — Discharge tables for rectangular weirs. 



0.566 7 1 . 8 . 

 Computed from the formula Q=Z.2471H':*- 0/1 8 flV. 







Discharge in cubic feet per second 







Discharge in cubic feet per second 



Head 



Head 



for crests of various lengths. 



Head 



Head 



for crests o 



various lengths. 



m 



in 



inches. 













m 

 feet. 



in 



inches. 









feet. 



1 











1 















1 foot. 



l.Sfeet. 



2 feet. 



3 feet. 



4 feet. 







1 foot. 



t.5feet. 



2 feet. 



3 feet. 



4 feet. 



0.20 



21 



0.291 



0.439 



0.588 



0.887 



1.19 



.86 



10* 



2.46 



3.72 



5.01 



7.59 



10.19 



.21 



2i 



.312 



.472 



.632 



.954 



1.28 



.87 



1°* 



2.50 



3.79 



5.10 



7.72 



10.36 



.22 



2| 



.335 



.505 



.677 



1.02 



1.37 



.88 



io* 



2.54 



3.85 



5.18 



7.85 



10.54 



.23 



2? 



.358 



.539 



.723 



1.09 



1.46 



.85 



10H 



2.58 



3. 92 



5.27 



7.99 



10.71 



.24 



21 



-3S0 



.574 



.769 



1.16 



1.55 



.90 



io|| 



2.62 



3.98 



5.35 



8.12 



10.89 



.25 



3 



.404 



.609 



.817 



1 23 



1.65 



.91 



ioh 



2.67 



4.05 



5.44 



8.25 



11.07 



.26 



3| 



.428 



.646 



.865 



1.31 



1.75 



.92 



11* 



2.71 



4.11 



5.53 



8.38 



11.25 



.27 



31 



.452 



.682 



.914 



1.38 



1.85 



.93 



11* 



2.75 



4.18 



5.62 



8.52 



11.43 



.28 



31 



.477 



.720 



.965 



1.46 



1.95 



.94 



HI 



2.79 



4.24 



5.71 



8.65 



11.61 



.29 



34 



.502 



.758 



1.02 



1.53 



2.05 



.95 



HI 



2.84 



4. 31 



5.80 



8.79 



11.79 



.30 



3| 



.527 



.796 



1.07 



1.61 



2.16 



.96 



Hi 



2.88 



4.37 



5.89 



8.93 



11.98 



.31 



3| 



.553 



.836 



1.12 



1.69 



2.26 



.97 



11§ 



2.93 



4.44 



5. 98 



9.06 



12.16 



.32 



Ql S 



.580 



.876 



1.18 



1.77 



2.37 



.98 



11! 



2.97 



4.51 



6.07 



9.20 



12.34 



.33 



3H 



.606 



.916 



1.23 



1.86 



2.48 



.99 



HI 



3.01 



4.57 



6.15 



9.34 



12.53 



.34 



4ft 



.634 



.957 



1.28 



1.94 



2.60 



1.00 



12 



3.06 



4.64 



6.25 



9.48 



12.72 



.35 



4* 



. 661 



.999 



1.34 



2.02 



2.71 



1.01 



121 





4.71 



6. 34 



9.62 



12.91 



.36 



4* 



.688 



1.04 



1.40 



2.11 



2.82 



1.02 



121 





4.78 



6.43 



9.76 



13.10 



.37 



4ft 



.717 



1.08 



1.45 



2.20 



2.94 



1.03 



12f 





4.85 



6.52 



9.90 



13.28 



.38 



4ft 



.745 



1.13 



1 51 



2.28 



3 06 



1.04 



124 





4 92 



6. 62 



10 04 



13.47 



.39 



4H 



.774 



1.17 



1.57 



2.37 



3.18 



1.05 



12- 5 - 





4.98 



6 71 



10.18 



13.66 



.40 



4H 



.804 



1.21 



1.63 



2.46 



3.30 



1.06 



12J 





5.05 



6.80 



10.32 



13.85 



.41 



4-ri 



.833 



1.26 



1.69 



2.55 



3.42 



1.07 



12H 





5 12 



6.90 



10.46 



14.04 



.42 



oft 



.863 



1.30 



1.75 



2.65 



3.54 



1.08 



12H 





5 20 



6.99 



10.61 



14.24 



■ 43 



5ft 



■ 893 



1.35 



1.81 



2.74 



3.67 



1.09 



13* 





5. 26 



7.09 



10.75 



14.43 



• 44 



5^: 



■ 924 



1.40 



1.88 



2.83 



3.80 



1.10 



13* 





5.34 



7.19 



10.90 



14.64 



• 45 



51 



■ 955 



1.44 



1.94 



2.93 



3.93 



1.11 



13* 





5.41 



7.28 



11.04 



14.83 



.46 



5?, 



.986 



1.49 



2.00 



3.03 



4.05 



1.12 



13* 





5.48 



7.38 



11.19 



15.03 



.47 



5| 



1.02 



1.54 



2.07 



3.12 



4.18 



1.13 



13* 





5 55 



7.47 



11.34 



15.22 



.48 



5! 



1.05 



1.59 



2.13 



3.22 



4.32 



1.14 



13H 





5 62 



7. 57 



11.48 



15.42 



.49 



51 



1.0,8 



1.64 



2.20 



3.32 



4.45 



1.15 



13} 1 





5 69 



7.66 



11.64 



15-62 



.50 



6 



1.11 



1.68 



2.26 



3.42 



4.58 



1.16 



13ft 





5 77 



7.76 



11.79 



15.82 



.51 



61 



1.15 



1.73 



2.33 



3.52 



4.72 



1-17 



14* 





5 84 



7.86 



11.94 



16.02 



.52 



61 



1.18 



1.78 



2.40 



3.62 



4.86 



1.18 



14* 





5 91 



7.96 



12.09 



16.23 



.53 



6| 



1.21 



1.84 



2.46 



3.73 



4.99 



1.19 



141 





5 98 



8.06 



12.24 



16.43 



■ 54 



64 



1.25 



1.89 



2.53 



3.83 



5. 13 



1.20 



14f 





6 06 



8.16 



12 39 



16.63 



.55 



6| 



1 28 



1.94 



2.60 



3.94 



5-27 



1.21 



144 





6 13 



8.26 



12.54 



16.83 



.56 



6! 



1.31 



1.99 



2.67 



4.04 



5.42 



1.22 



14f 





6 20 



8.35 



12. 69 



17.03 



.57 



6H 



1 35 



2.04 



2.74 



4.15 



5.56 



1.23 



14 : ! 





6 28 



8.46 



12.85 



17.25 



.58 



6H 



1 38 



2.09 



2.81 



4.26 



5.70 



1.24 



141 





6 35 



8 56 



12 99 



17.45 



.59 



7ft 



1 42 



2.15 



2.88 



4.36 



5.85 



1.25 



15 





6.43 



8.66 



13 14 



17.65 



.60 



7ft 



7ft 



1.45 

 1.49 



2.20 

 2.25 



2.96 

 3.03 



4.47 

 4.59 



6.00 

 6.14 



1.26 



1.27 



151 









13.30 

 13.45 



17.87 



.61 









18.07 



.62 



7ft 



7ft 



7H 



7fl 



7ft 



8ft 



8ft 



81 



81 



84 



si 



°8 



8f 



81 



9 



9i 



91 



9| 



1.52 



1 56 

 1 60 

 1.63 

 1.67 

 1.71 

 1.74 

 1.78 

 1.82 

 1 . 86 

 1.90 

 1.93 

 1.97 

 2.01 

 2.05 

 2.09 

 2.13 



2.31 

 2.36 

 2.42 

 2. 47 

 2.53 

 2.59 

 2.64 

 2 70 

 2.76 

 2.81 

 2.87 

 2.93 

 2 99 

 3. 05 

 3. 11 

 3.17 

 3.23 



3.10 

 3-17 

 3.25 

 3. 32 

 3.40 

 3.47 

 3.56 

 3.63 

 3.71 

 3.78 

 3.86 

 3.94 

 4.02 

 4.10 

 4.18 

 4.26 

 4.34 



4.69 

 4.81 

 4.92 

 5.03 

 5. 15 

 5.26 

 5.38 

 5.49 

 5.61 

 5.73 

 5.85 

 5.97 

 6.09 

 6.21 

 6.33 

 6.45 

 6.58 



6.29 

 6.44 

 6.59 

 6.75 

 6.90 

 7.05 

 7.21 

 7.36 

 7.52 

 7.68 

 7.84 

 8.00 

 8.17 

 8.33 

 8.49 

 8.66 

 8.82 



1.28 

 1.29 

 1.30 

 1.31 

 1.32 

 1.33 

 1.34 

 1.35 

 1.36 

 1.37 

 1.38 

 1.39 

 1.40 

 1.41 

 1.42 

 1.43 

 1.44 



15| 



154 



15| 



15J 



15|| 



15ft 



16ft 



16* 



16* 



16* 



16ft 



16ft 



16ft 



16-1-1 



17ft 



17ft 









13. 61 

 13.77 

 13. 93 

 14.09 

 14.24 

 14.40 

 14.56 

 14.72 

 14.88 

 15 04 

 15.20 

 15.36 

 15.53 

 15-69 

 15- 85 

 16. 02 

 16.19 



18.28 



.63 









18.50 



.64 









18.71 



.65 









18.92 



.66 









19.12 



.67 









19.34 



.68 









19. 55 



.69 









19.77 



.70 









19.98 



.71 









20.20 



.72 









20. 42 



.73 









20.64 



.74 









20.86 



.75 









21.08 



.76 









21.29 



.77 









21.52 



.78 









21.74 



.79 



9* 

 9| 

 9! 



9 tf 

 10* 



10ft 



2.17 

 2.21 

 2.25 

 2.29 

 2 33 

 2 37 

 2.41 



3.29 

 3.35 

 3 41 



3.47 

 3.54 

 3 60 

 3 66 



4.42 

 4.51 

 4.59 

 4.67 

 4.75 

 4.84 

 4.92 



6.70 

 6.83 

 6.95 

 7.08 

 7.21 

 7 33 

 7.46 



8.99 

 9.16 

 9.33 

 9.50 

 9.67 

 9.84 

 10.01 



1.45 

 1.46 

 1.47 

 1.48 

 1.49 

 1.50 



17f 



174 

 17| 

 17] 

 1"! 

 IS 









16.34 

 16.51 

 16.68 

 16. 85 

 17.01 

 17.17 



21.96 



.80 









22.18 



.81 









22.41 



.82 









22.64 



.83 









22.85 



.84 









23. 08 



.85 











