Pond Liner Slit with Water Underneath: Drain Tube Before Patch

1/4" slit in liner, water under liner prevents patching — rock caused it. Don't patch wet. Install sub-liner drain tube first.

Why Patching Fails Now

• Water pressure lifts liner → patch won't bond.
• Glue won't cure on wet surface.
• Groundwater will re-accumulate → new leak.

Immediate Fix: Drain the Water

1. Siphon/pump water from under liner — use low spot.
2. Let ground dry 24–48 hrs — fan/heater if needed.
3. Patch dry liner: EPDM primer + patch + roller. Works on clean, dry rubber.

Permanent Fix: Sub-Liner Drain (Do This Next Time)

1. Lay ½" perforated pipe in lowest area under liner.
2. Run to daylight (lower than pond).
3. Cover with geotextile.
4. Future water → siphon out in 30 sec.

Rock Prevention

• Remove sharp rocks before liner.
• Use 2" sand bed + geotextile under liner.
• Never skip underlayment — $0.25/sq ft saves liners.

Water under liner is a drainage problem, not a liner problem. Fix the drainage, then the liner holds.