Sand in Submersible Pumps: Causes and Solutions
Sand is one of the main factors that shorten submersible pump life. How sand damages a pump, where it comes from and practical ways to reduce it.
How sand damages a pump
The one problem no pump material solves on its own
Sand passes through the pump at high velocity with the water and wears the impeller, diffuser and bearing surfaces. As wear progresses the pump first loses flow and pressure, then the bearings loosen and vibration begins. With heavy sand the pump can jam and the motor draws excessive current at start. Stainless steel and cast iron are both affected; the solution is to reduce the sand reaching the pump, not to change the body material.
Hydraulic wear
As impeller and diffuser surfaces wear, head per stage falls and flow and pressure decline over time.
Bearing wear
As bearings loosen the shaft runs out of true, and noise and vibration increase.
Jamming
When the pump stops, sand in the rising main can settle back; at the next start the pump strains or locks.
Motor overload
A jammed or strained pump makes the motor draw excess current and trip the overload protection.
Where does the sand come from?
Insufficient well development
If the borehole was not properly cleaned and developed after drilling, fine material keeps coming with the water for a long time.
Unsuitable screen or gravel pack
If the screen slot size or gravel pack does not suit the aquifer, sand enters the well.
Excessive flow and drawdown
Pumping more than the well yield increases entry velocity and pulls sand from the aquifer.
Pump too close to the screen
If the intake is near the zone where sand enters, more sand reaches the pump.
Abrupt starts and stops
Every abrupt start creates a flow surge in the well and mobilises settled sand.
How to reduce sand problems
Develop the well
The well should be developed by the driller until the water runs clear. This is the most effective investment in pump life.
Match flow to well yield
Select the pump flow for the acceptable drawdown established by the pumping test. An oversized pump pulls sand from the well.
Adjust the intake position
Position the pump away from the zone where sand enters and well above the well bottom. If the pump is below the screen, a flow sleeve is required.
Use a sand separator
In wells where sand persists, a sand separator ahead of the pump reduces the sand that reaches it.
Use soft starting
Gradual starting with a soft starter or variable frequency drive reduces flow surges and sand movement in the well.
Throttle at first start
Start a new installation with the valve throttled and increase flow gradually as the water clears.
Choosing a pump for a sandy well
What to consider
The sand-channel rubber bearings used in FANPO stainless steel submersible pumps contribute to safe operation in sandy wells. Even so, where sand content is high, the intake position and well development matter more than the pump model or body material. For material selection see stainless steel vs cast iron; for products see stainless steel submersible pumps and cast iron submersible pumps.
Frequently asked questions
Is it normal for a submersible pump to deliver sandy water?
In a new well, some sand at first start can be expected. If sand keeps coming, the well has not been developed enough, the flow is too high for the well yield, or the screen is unsuitable.
Is a stainless steel pump more resistant to sand?
Not meaningfully. Sand wears the hydraulic surfaces of both materials. The solution is to reduce the sand reaching the pump.
Which parts of the pump does sand wear?
Impellers, diffusers and bearings are affected most. As wear progresses, flow and pressure fall and vibration increases.
Is a sand separator needed in every well?
No. A well-developed well that delivers clean water does not need one. Where sand persists, a separator can extend pump life considerably.
Which pump should I choose for my sandy well?
Send the casing diameter, dynamic water level, required flow and sand condition through the contact page, and our technical team will propose a suitable model and setting position.
Prepared by the FANPO engineering team · Last updated: 8 November 2026