Sump Pump Capacity

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Water Discharge Chart

Assume Gravity Flow about 6 f/s flow velocity, also suction side of pump Assume Average Pressure (20-100PSI) About 12 f/s flow velocity Assume”High Pressure” PEAK flow, About 18 f/s flow velocity*
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Pipe
Size ID(range) OD GPM* GPH* GPM* GPH* GPM* GPH*
1/2″ .50-.60′ .85″ 7 420 14 840 21 1260
3/4″ .75-.85″ 1.06″ 11 660 23 1410 36 2160
1″ 1.00-1.03″ 1.33″ 16 960 37 2220 58 3510
1.25″ 1.25-1.36″ 1.67″ 25 1500 62 3750 100 5940
1.5″ 1.5-1.60″ 1.90″ 35 2100 81 4830 126 7560
2″ 1.95-2.05″ 2.38″ 55 3300 127 7650 200 12000
2.5″ 2.35-2.45″ 2.89″ 80 4800 190 11400 300 17550
3″ 2.9-3.05″ 3.50″ 140 8400 273 16350 425 25650
4″ 3.85-3.95″ 4.50″ 240 14400 480 28800 700 42000
5″ 4.95-5.05″ 5.563″ 380 22800 750 45000 1100 66000
6″ 5.85-5.95″ 6.61″ 550 33000 1100 66000 1700 102000
8″ 7.96″ 8.625″ 950 57000 1900 114000 2800 168000