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Discharge Tables

The discharge tables here are for thin-plate weirs in general.  

Before relying on the full flow rates indicated on the tables below, compare the depths indicated in the tables versus your application.  The tables below have been calculated to their maximum rating and your installation may not have as much flow depth available as is shown in the tables. 

22 1/2º V-Notch Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.0089 Minimum Flow Rate (l/s) 0.2518
Maximum Head (ft) 2.00 Maximum Head (m) 0.6096
Maximum Flow Rate (cfs) 2.811 Maximum Flow Rate (l/s) 76.62
Equation=cfs, ft 0.4970*H2.5
Equation=l/s, m 274.4*H2.5
Download The Full Table Table is for maximum weir depth of 2-feet [60.96 cm]
30º V-Notch Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.0121 Minimum Flow Rate (l/s) 0.3425
Maximum Head (ft) 2.00 Maximum Head (m) 0.6096
Maximum Flow Rate (cfs) 3.824 Maximum Flow Rate (l/s) 108.3
Equation=cfs, ft 0.6760*H2.5
Equation=l/s, m 373.2*H2.5
Download The Full Table Table is for maximum weir depth of 2-feet [60.96 cm]
45º V-Notch Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.0185 Minimum Flow Rate (l/s) 0.5243
Maximum Head (ft) 2.00 Maximum Head (m) 0.6096
Maximum Flow Rate (cfs) 5.855 Maximum Flow Rate (l/s) 165.8
Equation=cfs, ft 1.035*H2.5
Equation=l/s, m 571.4*H2.5
Download The Full Table Table is for maximum weir depth of 2-feet [60.96 cm]
60º V-Notch Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.0258 Minimum Flow Rate (l/s) 0.7310
Maximum Head (ft) 2.00 Maximum Head (m) 0.6096
Maximum Flow Rate (cfs) 8.163 Maximum Flow Rate (l/s) 231.2
Equation=cfs, ft 1.443*H2.5
Equation=l/s, m 798.7*H2.5
Download The Full Table Table is for maximum weir depth of 2-feet [60.96 cm]
90º V-Notch Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.0447 Minimum Flow Rate (l/s) 1.267
Maximum Head (ft) 2.00 Maximum Head (m) 0.6096
Maximum Flow Rate (cfs) 14.14 Maximum Flow Rate (l/s) 400.5
Equation=cfs, ft 2.500*H2.5
Equation=l/s, m 1,380*H2.5
Download The Full Table Table is for maximum weir depth of 2-feet [60.96 cm]
120º V-Notch Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.0775 Minimum Flow Rate (l/s) 2.194
Maximum Head (ft) 2.00 Maximum Head (m) 0.6096
Maximum Flow Rate (cfs) 24.49 Maximum Flow Rate (l/s) 693.7
Equation=cfs, ft 0.4970*H2.5
Equation=l/s, m 274.4*H2.5
Download The Full Table Table is for maximum weir depth of 2-feet [60.96 cm]
1-foot Cipolletti Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.3012 Minimum Flow Rate (l/s) 8.529
Maximum Head (ft) 0.50 Maximum Head (m) 0.1524
Maximum Flow Rate (cfs) 1.190 Maximum Flow Rate (l/s) 33.71
Equation=cfs, ft 3.367*H1.5
Equation=l/s, m 557.7*H1.55
Download The Full Table Table is for maximum weir depth of 6-inches [15.24 cm]
1 1/2-foot Cipolletti Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.4518 Minimum Flow Rate (l/s) 12.79
Maximum Head (ft) 0.75 Maximum Head (m) 0.2286
Maximum Flow Rate (cfs) 3.281 Maximum Flow Rate (l/s) 92.91
Equation=cfs, ft 5.051*H1.5
Equation=l/s, m 743.6*H1.5
Download The Full Table Table is for maximum weir depth of 9-inches [22.86 cm]
2-foot Cipolletti Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.6023 Minimum Flow Rate (l/s) 17.06
Maximum Head (ft) 1.00 Maximum Head (m) 0.3048
Maximum Flow Rate (cfs) 6.734 Maximum Flow Rate (l/s) 190.7
Equation=cfs, ft 6.734*H1.5
Equation=l/s, m 1133*H1.5
Download The Full Table Table is for maximum weir depth of 1-foot [30.48 cm]
2 1/2-foot Cipolletti Weir
Minimum Head (ft) 0.20 Minimum Head (m) 0.0610
Miniumum Flow Rate (cfs) 0.7529 Minimum Flow Rate (l/s) 17.06
Maximum Head (ft) 1.25 Maximum Head (m) 0.3048
Maximum Flow Rate (cfs) 11.76 Maximum Flow Rate (l/s) 333.2
Equation=cfs, ft 8.418*H1.5
Equation=l/s, m 1487*H1.5
Download The Full Table Table is for maximum weir depth of 1.25-feet [38.1 cm]