Block paved drive

Been asked to wash a driveway they have put hypo down and power washed it off it looks quite good in parts, but there appears to be lines on it as if they have turned the nozzle on full blast and drawn like scribbles on it . How would I get those marks off by re power washing the whole drive or would i have to put hypo down , don’t fancy using chems.

The lines are called shadow stripping. You would have to 're clean with a pressure washer using a more uniformed cleaning pattern to remove it although chems would help.

Sent using the http://Window Cleaning Forums mobile app