Sand in Well Water

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You do want to remove the sand from the cold water supply before it reaches any hot water tanks, household appliances, motors, extra pumps, or valve seats.

We recently put in a well on our land, and we’re getting a lot of sand in our well water. Our neighbors say this is a common problem. What can be done to prevent the grit from getting into our plumbing?

Solving Water Problems: Sand in Well Water

I’m missing some important details about your location and situation, so I will offer several suggestions that cover some possible solutions.

Schedule a face-to-face meeting with your well driller to discuss the problem and possible remedies to remove sand from your well water. The key topics will depend strongly on the hydrogeological details of your property. For example, if your well is so deep that it penetrates a bedrock aquifer (either a water table aquifer or a confined aquifer), then it would be a rare condition for the water itself to contain sand and would indicate that the well casing is not properly sealed at the top of the bedrock. The driller may be able to seal the casing properly.

If your well is fairly shallow, so that it penetrates only the overburden (soil, sand, and gravel) forming a water table aquifer, then the driller may have selected slots of an incorrect size for the slotted portion of the well casing. In certain situations, the driller may be able to install new casing with the proper slots, although this is sometimes too difficult or costly.

If one of the preceding methods can’t be used, then explore the possibility of wrapping the pump intake with a nylon based “geotechnical” fabric often used by civil engineers in the field. The desirability of this option depends on whether the inside diameter of your well casing and the outside diameter of your pump intake will allow a physical fit. It also depends on the prevalence of the sand, the fineness of the sand and the mesh of the nylon fabric used as a filter on the pump intake. If you select the right combination, you may not have to check or change this filter fabric more than once a year. (On the other hand, you may have to do so much more often.)

If none of the above will work in your situation, you may be able to install either an in-line holding tank (possibly pressurized to supply the water pressure in your home) which will allow the sand to settle for periodic removal and/or some kind of in-line canister filter so your well water is clear. Such basement-located units will require maintenance to remove the collected sand.

You do want to remove the sand from the cold water supply before it reaches any hot water tanks, household appliances, motors, extra pumps, or valve seats–and especially before the water goes to a septic tank and leaching field for disposal.

Finally, you might want to contact several local plumbers and contractors to discuss these ideas with them and to find out how your neighbors cope with this problem.

David Burmaster, consultant on surface — and groundwater quality and hazardous-waste management