Find your horsepower in the row, then read across. Total head is the lift from the pumping water level to the discharge, plus the pressure you want at the tank (2.31 ft for every PSI), plus friction in the drop pipe.
Total head in feet · curves end at 32–39.5 GPM
| HP |
0 GPM (Shut-off) |
7.5 GPM |
20 GPM |
27.5 GPM |
30 GPM |
| 1/2 HP |
122 ft |
109 ft |
80 ft |
56 ft |
46 ft |
| 3/4 HP |
152 ft |
138 ft |
107 ft |
73 ft |
61 ft |
| 1 HP |
219 ft |
202 ft |
150 ft |
113 ft |
97 ft |
| 1 1/2 HP |
282 ft |
259 ft |
204 ft |
159 ft |
140 ft |
| 2 HP |
374 ft |
342 ft |
263 ft |
193 ft |
163 ft |
| 3 HP |
507 ft |
469 ft |
362 ft |
266 ft |
226 ft |
| 5 HP |
796 ft |
736 ft |
576 ft |
426 ft |
366 ft |
Read from the published curve in the Pumps by Baker catalog (Sept 2025, rev 3/26), p. 64, digitized and rounded down, at the flows nearest 20%, 50% and 75% of the curve’s 39.9 GPM end. 0 GPM is the printed shut-off. The last column is the last flow every curve reaches; the curve ends are named in the table title.
Output in GPM at 30 PSI (switch cut-in), by depth to water
| HP |
25 ft |
50 ft |
100 ft |
150 ft |
200 ft |
250 ft |
300 ft |
| 1/2 HP |
15.93 |
2.93 |
— |
— |
— |
— |
— |
| 3/4 HP |
23.22 |
16.71 |
— |
— |
— |
— |
— |
| 1 HP |
29.81 |
26.22 |
17.35 |
— |
— |
— |
— |
| 1 1/2 HP |
33.65 |
31.08 |
25.26 |
17.91 |
6.06 |
— |
— |
| 2 HP |
— |
33.26 |
29.37 |
24.97 |
19.79 |
13.16 |
1.33 |
| 3 HP |
— |
35.85 |
33.16 |
30.28 |
27.12 |
23.62 |
19.61 |
| 5 HP |
— |
38.3 |
36.8 |
35.2 |
33.5 |
31.7 |
29.8 |
Output in GPM at 50 PSI (switch cut-out), by depth to water
| HP |
25 ft |
50 ft |
100 ft |
150 ft |
200 ft |
250 ft |
300 ft |
| 1/2 HP |
— |
— |
— |
— |
— |
— |
— |
| 3/4 HP |
8.81 |
— |
— |
— |
— |
— |
— |
| 1 HP |
22.80 |
18.14 |
2.61 |
— |
— |
— |
— |
| 1 1/2 HP |
28.74 |
25.74 |
18.56 |
7.42 |
— |
— |
— |
| 2 HP |
— |
29.68 |
25.33 |
20.23 |
13.75 |
2.92 |
— |
| 3 HP |
— |
33.38 |
30.50 |
27.37 |
23.90 |
19.94 |
15.19 |
| 5 HP |
— |
36.9 |
35.3 |
33.6 |
31.9 |
30.0 |
28.0 |
Output tables as printed in the Pumps by Baker catalog (Sept 2025, rev 3/26), pp. 63-64, at the 30 and 50 PSI rows. Riser-pipe friction is not included (manufacturer note): add it for long or small drop pipe. — marks a point A.Y. McDonald does not print for that horsepower.
Best operating range: the published curve shades the most efficient operating range for each model; the catalog prints no figures for it. The curve is in the image gallery.