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Do I Need to Replace My PDC?

In order to determine if you need to replace your PDC it is important to understand why your PDC is blocked.  If your PDC is blocked due to a grease build up it may not be necessary to replace the PDC.  The sewer pipe itself could be in perfect condition.  Once the cause of the blockage is removed the PDC should be running smooth and no further action is needed.

On the other hand, the PDC may have collapsed and there is no other solution other than to replace the PDC.  Another situation is when the PDC is starting to deteriorate due to cracks in the pipe wall, etc., but the PDC is in good enough shape to allow the PDC to be lined.  Lining a PDC is when a new layer is placed inside the PDC pipe.  Lining a PDC eliminates the need to dig up the original pipe to replace it with a new PDC resulting in less of a disturbance to your property.

In order to determine the source of the PDC back-up it is suggested that a qualified plumber or drainage specialist properly investigate the problem and recommend the appropriate solution.  In addition, contact the City of London at the numbers at the top right of this screen to ensure the City’s sewers, generally under the road, are running properly.  City staff will come out to your property to review the City’s sewer main at no cost to the property owner.  It is ideal to call the City when the back-up is occurring in order to analyze the City sewers and flooding situation accurately.  Note that the City of London does not share basement flooding information with any external parties.

Examples of blockages in PDC's:

Partial blockage in a PDC due to grease build up.Major blockage due to grease build-up.










Partial blockage due to grease build-up.                               Almost full blockage due to grease build-up.


Blockage in PDC due to tree roots

Partial blockage in PDC due to tree roots










Partial blockage due to tree roots.                                           Almost full blockage due to tree roots.


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