Hand-Dug Well Maintenance and Repair

Annual Inspection Checklist

Most well problems announce themselves before they become serious. A yearly inspection catches them early.

At the surface:

• Check the wellhead cover for cracks, gaps, or missing sections. Any opening larger than 1/4 inch lets insects and surface water in.
• Inspect the concrete apron (the pad surrounding the well opening) for cracks. Surface water running toward the well opening carries contamination directly into your water supply.
• Look for animal tracks or droppings near the well. Small animals can enter through damaged covers.
• Check that the apron slopes away from the well, not toward it. Water should drain outward at least 3 feet in every direction.

Inside the well (from above, with a flashlight):

• Look for cracks or gaps in the casing material (stone, brick, or concrete rings).
• Check the water level. Significant drops from previous years may indicate reduced aquifer recharge or a casing leak above the water table.
• Look for floating debris, discoloration, or oily sheen on the water surface.
• Listen for unusual sounds when water is still — trickling where there should be none may indicate surface water infiltration.

Clearing Sediment

Sediment accumulates on the well floor over time, reducing storage volume and degrading water quality. Signs you need to clear it: reduced yield, sandy or gritty water, or visible turbidity.

Tools needed: Bucket with a long rope, a weighted sediment pump (or a bailer made from PVC pipe with a foot valve), safety harness if you plan to descend.

Disinfecting After Contamination

Flooding, animal intrusion, or repair work all require full well disinfection before drinking the water again. The CDC-recommended procedure uses household bleach.

What you need: Unscented household bleach (5-8% sodium hypochlorite), a clean bucket, rope, and water test kit or strips.

Repairing Casing Cracks and Gaps

Stone, brick, and concrete casing develops cracks over time from frost heave, soil movement, and age. Any gap above the water table is a contamination pathway.

Materials needed: Hydraulic cement or fast-setting mortar, water, mixing container, pointing trowel, safety rope.

For shallow cracks you can reach from above:

• Wire-brush loose material from the crack.
• Mix hydraulic cement to a stiff consistency (it sets fast — work in small batches).
• Pack the crack firmly, slightly overfilled, and smooth with a trowel.
• Hydraulic cement sets in minutes and bonds wet surfaces — it works even if the casing is damp.

For cracks requiring descent:

• Never descend more than five feet without a harness, safety rope, and a surface attendant.
• Test with a candle flame before descending — if the flame goes out or wavers upward, oxygen is depleted.
• Wear old clothes. Bring only what you need: cement in a small container, trowel, brush.
• Work quickly. The well environment is physically demanding and often disorienting.

Repairing the Wellhead Apron

A cracked or improperly sloped apron is one of the most common sources of bacterial contamination in hand-dug wells. Surface water follows cracks directly into the casing.

For small cracks: Clean the crack with a wire brush, blow out debris, fill with hydraulic cement or exterior concrete caulk. Seal before the next rain.

For major apron failure: Break out the old apron with a sledgehammer and cold chisel. Excavate 6 inches around the well casing to expose the upper section. Pour a new apron of at least 3-inch thick concrete, sloped away from the casing at a minimum 1/4 inch per foot. Embed the apron against the casing, not simply touching it — the joint between apron and casing is where infiltration happens.

Improving a Poorly Built Well

Many hand-dug wells were built without proper contamination barriers. If you are working with a well that was dug quickly in an emergency or by someone without training, these improvements make a significant difference.

Add a grout seal: The annular space between the outer casing and the surrounding soil should be filled with bentonite clay or concrete grout for at least the top 10 feet. This prevents surface water from running down the outside of the casing.

Build a raised curbing: The wellhead should extend at least 12 inches above the finished ground surface. Lower curbing allows flood water to run directly in.

Improve the cover: A properly fitted cover keeps out insects, animals, and airborne contamination. It should have a hinged access point, mesh ventilation screened to 20 mesh or finer, and a locking mechanism in any shared-use situation.

Testing Water Quality

Physical repairs mean nothing if you are not testing the result. At minimum, test for:

• Total coliform bacteria — the basic indicator of fecal contamination
• Nitrates — elevated in areas with heavy agriculture or septic systems
• pH — should be between 6.5 and 8.5 for safe drinking

Basic test kits are inexpensive and give reliable results. Test after any disinfection procedure, after repairs, and every six to twelve months in normal use.

If a test shows persistent bacterial contamination after proper disinfection, the source is likely continuous infiltration — a casing crack, a failed apron joint, or surface drainage running toward the well. Trace the water path and fix the physical problem before disinfecting again.

When to Start a New Well

Some wells cannot be saved. Consider abandonment and replacement when:

• The casing has collapsed or the bore has shifted, creating an unrepairable gap
• Persistent contamination returns after multiple proper disinfections
• Water yield has dropped below functional levels despite clearing sediment
• The aquifer itself has failed (rare, but happens in severe drought)

When abandoning a well, fill it properly. An unsealed abandoned well is a contamination conduit for the groundwater that may supply neighboring wells. Fill with clean gravel to within 10 feet of the surface, then concrete to grade. Cap with a concrete plug at the surface.