How to choose a pump for an irrigation system
Surface vs. submersible, calculating flow rate and head, pump station with a pressure tank. Practical recommendations.
20 min
Reading time
Medium
Difficulty
5 steps
Calculation
-40%
VFD savings
Pump types for irrigation
| Type | Max. suction depth | Application | Price |
|---|---|---|---|
| Surface centrifugal | 7–8 м | Barrel, well up to 7 m, municipal water supply | 3000–8000 грн |
| Surface with ejector | 8–12 м | Well 7–12 m, medium-depth borehole | 5000–12000 грн |
| Submersible borehole | Installation depth up to 150 m | Borehole > 8 m, high flow rates | 8000–40000 грн |
| Submersible drainage | Operates in dirty water | Pond, rainwater tank | 4000–15000 грн |
| Pump station with pressure tank | 7–8 м | Systems with intermittent use, house + irrigation | 7000–20000 грн |
| Booster pump | - | Boosting municipal water pressure | 5000–15000 грн |
Calculation example: irrigating 1,000 m² of vegetables
- Area: 1,000 m², drip tape 1.6 L/h, 20 cm spacing
- Total emitters: ~4,000 pcs
- Total flow Q: 4,000 × 1.6 = 6,400 L/h = 6.4 m³/h
- System operating pressure: 1.5 bar (drip) = 15 m water column
- Mainline losses (50 m): 2 m
- Filter: 0.3 bar = 3 m
- Elevation lift: 3 m
- Suction depth from well: 6 m
- Required head H: 15 + 2 + 3 + 3 + 6 = 29 m
- 20% margin: 35 m
Result: A pump rated at 6.4 m³/h @ 35 m head is needed, ~1.2 kW. Suitable models: Grundfos JP 5, Wilo Jet HWJ, Pedrollo JSWm 2CX. For a borehole deeper than 8 m — submersible Grundfos SQ 2-35.
Q-H curve: why it matters
Every pump model has a characteristic curve: the relationship between head H and flow Q. As Q increases, head drops.
- The operating point should be in the MIDDLE of the curve (40–60% of Qmax). At the far left or right — wear accelerates
- Far left point (low Q, high H) — overload, overheating
- Far right (high Q, low H) — cavitation, impeller wear
- If your requirement falls outside the curve — choose a different model; do not operate at the extreme points
Selection by water source
- Municipal supply (pressure 2.5+ bar): no pump needed. If pressure is lower — booster at 20–50 L/min (Grundfos UPA, Wilo PB-201 EA)
- Barrel/tank at 2+ m elevation: no pump needed for drip (gravity feed). For sprinklers — surface pump, 0.6 kW
- Well up to 7 m: surface centrifugal or vortex (Pedrollo JSWm, Grundfos JP, Wilo Jet)
- Well 7–12 m: surface with external ejector or submersible (Grundfos SQ, Wilo TWU)
- Borehole 8–50 m: submersible 3" or 4" (Grundfos SP/SQ, Wilo TWU 4", Pedrollo 4SR)
- Pond / river: surface self-priming with coarse filter + sand filter in the system
- Rainwater: submersible drainage or external self-priming with a float switch
Pressure tank vs. VFD (Variable Frequency Drive)
Two ways to avoid frequent pump cycling (repeated start-stop kills pump life in 2–3 seasons).
- Pressure tank (24–100 L): a tank with a rubber diaphragm. A pressure switch turns the pump on when pressure drops and off when the tank fills. Simple, reliable, UAH 2,000–5,000. For home gardens and residential irrigation.
- VFD (Variable Frequency Drive): smooth speed control. Stable pressure, 30–40% electricity savings, soft start without water hammer. UAH 10,000–30,000. For permanent large-scale systems.
- Built-in automation (Grundfos CMBE, Wilo Varios PICO): pump + controller + VFD in one unit. Plug-and-play, no pressure tank needed. More expensive but compact.
For commercial systems from 1 ha
- Pump station with 2 pumps (primary + backup) with automatic switchover
- VFD is mandatory — electricity savings of hundreds of thousands of hryvnias per season for 5+ ha systems
- Protection: suction strainer, pressure relief valve, low-level cutoff, dry-run protection
- Master valve + flow sensor + master controller — automatic control of the entire network
- Geological assessment of the borehole BEFORE design: static level, dynamic level, yield. Without this — risk of dry-run failure
- Brands for B2B: Grundfos CR/SP/CM, Wilo MVI/TWU, Lowara e-SV, Pedrollo 4SR, Caprari E4XP
- Standards: EN ISO 9906 (centrifugal pump testing), EN 1717 (backflow prevention), ISO 15874 (PPR mainline)
Pump group components
Our catalog offers all components for the pump group: fittings, filters, pressure switches, PPR connections.