An interior perimeter French drain functioned effectively for 18 years, but now its efficiency has declined. Unfortunately, the company that installed it has gone out of business. What steps can we take to diagnose potential issues like clogs, sump problems, or improper grading? Additionally, how can we retrofit the system for renewed performance without resorting to a complete demolition?
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Okay, so the gravel trench or pipe is likely blocked with silt, or the pump is stuck. First, check the pit for junk, and see if the pump starts and the line is clear. If no water’s getting to the pit, you might need to open the floor, flush/replace the pipe, and redo the filter and gravel so it won’t clog up again. Sometimes you can jet or vacuum it from access points, but after this long, a partial fix is often what it needs.
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First and foremost
locate and clear any clogs in the pipe or gravel using a plumber’s snake or high-pressure water.
If blockages or collapse are severe, consider removing the old drain section, replacing it with perforated pipe wrapped in filter fabric
Ensure it slopes properly to the outlet for effective drainage.
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Check for clogs in drain lines, test the sump pump, and inspect grading outside. If issues persist, flush the system, add clean-outs, upgrade the pump, or tie in extra drains no full tear-out needed.
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Clear blockages, repair damaged sections, or consider replacing the French drain system.
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Fixing an interior French drain that stopped working after 18 years requires a systematic approach to identify and address the issue. Given the age of your system, it’s likely that debris accumulation, clogged pipes, or worn-out components are causing the problem.
Inspection and Diagnosis
- Visual Inspection: Check the drain’s surface and surrounding areas for signs of debris accumulation, erosion, or water damage.
- Water Flow Test: Run water through the drain to observe its flow rate and identify potential blockages.
- Camera Inspection: Consider hiring a professional to perform a camera inspection of the drain pipes to pinpoint blockages or damage.
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Start by inspecting and cleaning the drain channels, flushing with water to clear sediment. Check the sump pump for wear, test float switches, and verify power supply. Ensure grading directs water toward the system. If needed, retrofit with new cleanouts, pump upgrades, or added discharge lines to restore performance.
Start by inspecting the sump pump,check power, float switch, and discharge line for blockages or freezing. Use a plumbing snake or flush ports (if present) to clear sediment from the drain channels. Look for signs of collapsed pipe, root intrusion, or silt buildup at accessible points. Improve surface grading and gutters to reduce water load. If sections remain clogged, retrofit with added cleanouts, a secondary sump, or localized trenching to restore flow avoiding full system demolition.
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