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 30.5–35 GPM
| HP |
0 GPM (Shut-off) |
7.5 GPM |
17.5 GPM |
27.5 GPM |
30 GPM |
| 1/2 HP |
146 ft |
135 ft |
103 ft |
60 ft |
43 ft |
| 3/4 HP |
203 ft |
188 ft |
150 ft |
83 ft |
62 ft |
| 1 HP |
261 ft |
240 ft |
186 ft |
98 ft |
73 ft |
| 1 1/2 HP |
358 ft |
336 ft |
262 ft |
138 ft |
100 ft |
| 2 HP |
462 ft |
423 ft |
332 ft |
192 ft |
144 ft |
| 3 HP |
602 ft |
553 ft |
432 ft |
242 ft |
180 ft |
| 5 HP |
958 ft |
873 ft |
713 ft |
380 ft |
281 ft |
Read from the published curve in the Pumps by Baker catalog (Sept 2025, rev 3/26), p. 34, digitized and rounded down, at the flows nearest 20%, 50% and 75% of the curve’s 35 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 |
20.53 |
14.28 |
— |
— |
— |
— |
— |
| 3/4 HP |
24.74 |
21.40 |
12.71 |
— |
— |
— |
— |
| 1 HP |
27.70 |
25.39 |
20.06 |
12.92 |
— |
— |
— |
| 1 1/2 HP |
— |
28.71 |
25.26 |
21.30 |
16.53 |
10.04 |
— |
| 2 HP |
— |
31.47 |
28.79 |
25.88 |
22.65 |
18.98 |
14.61 |
| 3 HP |
— |
31.97 |
30.18 |
28.28 |
26.25 |
24.06 |
21.66 |
| 5 HP |
— |
33.70 |
32.62 |
31.50 |
30.35 |
29.16 |
27.91 |
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 |
5.68 |
— |
— |
— |
— |
— |
— |
| 3/4 HP |
18.16 |
13.54 |
— |
— |
— |
— |
— |
| 1 HP |
23.27 |
20.51 |
13.58 |
— |
— |
— |
— |
| 1 1/2 HP |
— |
25.53 |
21.62 |
16.93 |
10.65 |
— |
— |
| 2 HP |
— |
29.00 |
26.11 |
22.91 |
19.28 |
14.97 |
9.38 |
| 3 HP |
— |
30.32 |
28.43 |
26.41 |
24.23 |
21.85 |
19.20 |
| 5 HP |
— |
32.70 |
31.59 |
30.44 |
29.25 |
28.01 |
26.71 |
Output tables as printed in the Pumps by Baker catalog (Sept 2025, rev 3/26), pp. 33-34, 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.