Well Casing Repair: Signs of Damage & Repair Options

What Is Well Casing?

Purpose

Well casing is the pipe that lines your well bore. It serves multiple critical functions:

• Structural support: Prevents borehole collapse
• Contamination barrier: Keeps surface water out
• Seal: Prevents mixing between aquifer layers
• Pathway: Houses pump and provides route for water

Casing Materials

• Steel: Most common, strong but can corrode
• PVC: Won't corrode, less strong
• Stainless steel: Corrosion-resistant, expensive
• Galvanized steel: Older wells, limited life

Components

• Surface casing: Upper section, grouted to prevent contamination
• Production casing: Main well casing
• Well cap: Seals top of casing
• Grout seal: Cement between casing and rock

Common Casing Problems

Corrosion

• Steel casing rusts over time
• Aggressive water chemistry accelerates it
• Creates holes, weak spots
• Most common in wells 20+ years old

Cracks or Holes

• From corrosion, impact, or settling
• Allow surface water to enter
• Source of contamination

Joint Failures

• Connections between casing sections
• Can separate due to movement or corrosion
• Creates gaps for contamination

Grout Seal Failure

• Cement around casing cracks or washes away
• Opens pathway for surface contamination
• Water can bypass sealed zone

Collapse

• Rare but serious
• Casing buckles inward
• Can trap or damage pump
• Often requires new well

Signs of Casing Damage

Water Quality Changes

• Muddy water after rain (surface water entering)
• Color or taste changes
• Increase in sediment

Contamination Issues

• Failed bacteria tests that keep recurring
• Bacteria returns shortly after shock treatment
• Nitrates appearing or increasing

Physical Signs

• Visible rust at wellhead
• Damaged well cap
• Water seeping around well casing at surface

Performance Changes

• Water level drops unusually
• Yield changes unexpectedly
• Pump pulls sand (may indicate hole below screen)

Inspection Methods

Video Camera Inspection

Most definitive diagnostic tool.

• Lowered into well on cable
• Shows visual condition of casing
• Identifies holes, corrosion, deposits
• Cost: $300-$600

Water Testing

• Bacteria tests
• Nitrate tests
• Indicators of surface water intrusion

Physical Inspection

• Wellhead condition
• Cap seal
• Visible casing at surface

Flow Testing

• Changes in yield
• Water level behavior
• Recovery rate

Repair Options

Well Cap Replacement

If damage is only at the top.

• Replace cracked or missing cap
• Seal vermin-proof
• Cost: $100-$400

Grout Seal Repair

If surface seal has failed.

• Re-grout around casing
• Prevents surface contamination
• Cost: $500-$2,000

Liner Installation

Most common casing repair for corrosion/holes.

• Smaller diameter casing inserted inside damaged casing
• Seals off damaged areas
• Reduces well diameter slightly
• Cost: $2,000-$8,000
• Requires pulling pump

Packer Seal

For isolated hole or failed joint.

• Inflatable seal placed at damage point
• Less invasive than full liner
• Cost: $1,000-$3,000

Well Rehabilitation

Comprehensive approach.

• Address multiple issues
• May include liner, grouting, cleaning
• Cost: $5,000-$15,000

Well Replacement

When damage is too severe.

• Collapsed casing
• Extensive corrosion throughout
• Cost of repair approaches new well cost
• Cost: $15,000-$50,000+

Frequently Asked Questions

How do I know if my well casing is damaged?

Signs include water quality changes after rain, recurring bacteria, increased sediment, visible damage at wellhead. Camera inspection provides definitive diagnosis.

How long does well casing last?

Steel casing: 20-50 years depending on water chemistry. PVC: 50+ years. Galvanized: 15-30 years. Regular inspection helps catch problems early.

Can well casing be repaired?

Yes, usually with a liner inserted inside the damaged casing. This seals off holes and corrosion. Severely collapsed casing may require new well.

How much does a well liner cost?

Typically $2,000-$8,000 depending on depth and conditions. Includes pump pull and reinstall.

Is bacteria in my well from casing damage?

Possibly. If bacteria returns after shock treatment, damaged casing allowing surface water entry is a common cause.