Does lignin causes the cell wall to be impermeable to water ?

Yes, lignin is a hydrophobic polymer that makes the cell wall impermeable to water. It is a major component of the secondary cell wall in many plant tissues, providing rigidity and strength to the cell wall. Lignified cell walls are less permeable to water and gases than unlignified cell walls, which helps with water and nutrient transport and also provides protection from pathogens and environmental stress.