One who excavates square uncovered waterway lacking volume (8)

I believe the answer is:

quarrier

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'one who excavates square uncovered waterway lacking volume' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.

This is all the clue.

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(Another definition for quarrier that I've seen is " Man of rock".)

I've seen this clue in The Times.

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