Sand in Well Water: What It Does to a Deep Well Pump

A deep well pump is built for clean water. Sand wears the impellers and guide bowls, opens up the clearances and eats into the bearings. Line-shaft deep well pumps are especially sensitive; their sand content should stay at about 0.01% or less.

Signs of a sandy well

• Sand settling in a bucket of water taken at the outlet
• Flow falling over a few months while the water level is unchanged
• Noise from the pump, or a current that creeps up
• Worn, rounded impeller edges when the pump is lifted

How to reduce the damage

• Develop a new well properly before the permanent pump goes in, so the fine sand is cleared from around the screen
• Do not set the pump right at the screen or near the bottom of the well; keep the motor at least 1 m above the bottom
• Avoid pumping a well harder than it can yield, which draws more sand
• If a line-shaft pump has pumped sandy water, flush it with clean water before stopping it
• Inspect the pump at every service and replace worn parts before they fail