Diagram of Sanitary Sewage in Foundation:
This diagram depicts sanitary sewage effluent that is being picked up in the perimeter weeping tile and is being drained into the internal sump pit in the building. This may indicate a break in the pipe between the building and the tank, which would cause the sanitary sewage to leak into the foundation backfill and into the weeping tile.
(click on the image to enlarge)
Diagram of Blockage in Inlet Pipe:
A cause of sanitary sewage backup into a building is blockage of the
pipes in the sanitary sewage system. If the sewage is backing up into
the building the septic tank must be opened and examined. If the
liquid level in the tank is below the level of the inlet pipe then
there is a blockage between the building and the inlet of the tank. A
plumbing contractor can remove this type of blockage using a plumbing
snake.
(click on the image to enlarge)
Diagram of Blockage in Outlet Pipe:
If the level of sanitary sewage in the tank is above the inlet pipe,
the blockage is on the outlet side of the tank and may be in the tile
bed. A high level of sewage within the tank could also indicate that
the entire leaching bed is saturated and that the entire leaching bed
is saturated and that the ground can no longer absorb the liquid.
(click on the image to enlarge)
Diagram of Bio Mat:
The saturation of a leaching bed is one of the most serious causes of
malfunction of a septic system. Saturation occurs when the receiving
soil surrounding the leaching bed cannot accept any more effluent.
Blockage is usually caused by clogging of the soil by the Biomat which
is created under the tile trench.
(click on the image to enlarge)
Leeds, Grenville and Lanark District Health Unit -
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