Cover depth

This is the depth from the surface to the top (of the outer surface) of a pipe. In cases where paving or a pavement is applied to a surface, the cover might apply to the underside of this overlay, rather than the finished surface.

Minimum cover depths are set to prevent damage of pipes due to vehicles and other imposed loads. Backfill and soil act as cushioning agents provided a suitable depth is maintained. Pipe manufacturers provide recommendations on suitable depths and classes (strengths) of pipes. Maximum cover depths are also specified in manufacturer’s manuals but recommendations are often complex, being influenced by the type of bedding and the class of pipe.

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Cover depths for particular types of pipes are set in the Pipe Data Base.

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