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c-factor vs roughness height extremes

In the bookAdvanced Water Distribution Modeling and Management” I found the following:

If the differences in pressures and flows between actual conditions and predicted conditions are so great that unrealistic and unexplainable pipe roughness values (less than 30 or more than 150) or major adjustments in demands must be used to achieve calibration, then chances are good that the discrepancy is the result of a closed or partially closed valve or errors in system mapping.

The numbers less than 30 or more than 150 are Hazen-Williams c-factor. But when talking in terms of Darcy-Weisbach roughness height (e) what would be the extremes that one could draw the same conclusions from?