It blocks again every year and nobody is flushing anything they should not
In free-draining sand a defect lets the ground into the pipe, so it silts up with material nobody put down it. Clearing alone never lasts.
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A paver that rocks and a path that has dropped: where did the ground go?
Material that moved into a drain came from somewhere. In sand that leaves a void, and the void works its way to the surface.
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Every leak article tells you to look for a wet patch. Here there will not be one
The ground drains water vertically, so no wet patch or green grass ever forms. What to use instead, and why the meter is the only real test.
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