Bored Well vs Drilled Well: Which One Does SC Land Need?

A bored well is a wide, shallow hole lined with concrete rings. A drilled well is a narrow, deep hole with a steel or PVC pipe down to the water. In South Carolina, almost every new home well is drilled. The bored well is what you find already sitting on older land.

What's the difference between a bored well and a drilled well?

Width and depth. South Carolina's well rules define a bored well as a large-diameter well, "commonly equal to or greater than 24 inches," built shallow, with casing of rock, concrete or ceramic (SC Regulation 61-71). A drilled well is a few inches across and runs far deeper. Austin Drilling's Midlands wells typically run 100 to 400 feet or more.

How are they built? Differently. A bored well is cut with a big bucket auger and lined with concrete tiles about three feet long, so there's a joint every three feet (University of Kentucky). A drilled well is cased with pipe and sealed with grout pumped around the casing.

Where does each one get its water? That's the real difference. A bored well sits in the loose, weathered clay above the rock. A drilled well goes through it and pulls from cracks in the rock below.

Why do bored wells go dry and get dirty first?

Because they drink from the top of the water table. The USGS puts its porosity at "about 20 to 30 percent," far more than the solid rock beneath. But it's also the first layer to drop in a dry summer. Where that layer is thin, the USGS says wells "are more likely to go dry during the summer months or periods of drought."

Dirty water is the other problem. Septic drainage and barnyard runoff move through that same shallow layer. Every tile joint is a possible way in. South Carolina flags bored wells for extra setback distance "because they are under water-table conditions" (Regulation 61-71). Our article on coliform bacteria in well water explains how that shows up in a test.

Which one should you put on your land?

Drilled. The state agrees. Regulation 61-71 requires a drilled well's grout seal to start at least 20 feet down and says the Department "discourages wells less than 20 feet" for drinking water. A bored well only has to be grouted to 15 feet.

People still ask us to "dig" a well. One recent message asked for a well dug for an off-grid tiny home. Another had an old farm field and needed a well put out. Both get a drilled well. Our piece on how deep a well is in South Carolina covers what depth to expect. Austin Drilling has drilled more than 13,000 of them since 1960.

How can you tell which kind of well you already have?

Look at the top. A bored well shows a concrete ring two feet wide or more, often with a heavy concrete lid. A drilled well shows a steel or PVC pipe, usually under eight inches across, with a bolted cap. Can't tell? Send us a photo.

Some older coastal-plain properties have a 2-inch pipe instead. That's a small driven or jetted well, and it's neither of these.

What if the old bored well is still on the property?

Deal with it before it deals with you. Buyers inherit them without knowing. Under Regulation 61-71, any well out of service for more than 36 months has to be permanently abandoned by a licensed driller. An open bored well is a fall hazard and a straight path for contamination into the groundwater your new well shares.

Found one? Start with our guide to an old well on your property. If it can't go back in service, we handle well abandonment.

FAQ

What are the four main types of wells?

Dug, bored, driven and drilled. Driven wells are small pipes hammered into sand. Drilled wells are the deep, cased wells nearly every new South Carolina home uses.

How deep should a water well be drilled?

Deep enough to reach clean, steady water. In the SC Midlands that usually means 100 to 400 feet or more. A free site assessment from Austin Drilling tells you before any rig shows up.

Can I drink water straight from a bored well?

Not until it's tested. Shallow wells carry a higher risk of bacteria and runoff.

Can a bored well be converted to a drilled well?

No, you drill a new one. The old bored well then gets properly abandoned. Call Austin Drilling at (803) 926-5402 in West Columbia or (803) 926-7080 in Newberry. We're open Monday through Friday, 7am to 6pm, and Saturday by appointment.