To cause a water head to be minimum, prevent noise and further not to prevent an efficient flow of sucked air in a cooling tower by a method wherein a water collecting device having an aeration characteristic is installed just below a filling material block.

This water collecting device is comprised of a plurality of trough members 12 arranged just below a filling material block and spaced apart from each other to enable a clearance communicated in a vertical direction to be prohibited and of a plate member 16 suspended to flow water from the trough members 12 in a downward direction. The trough members 12 are comprised of trough segments 12a arranged with a clearance S from each other and slant plates 12b extended from the lower surface of the filling material block up to the trough segments 12a and then the slant plates 12b are constructed to close the clearance S of the trough segments 12a in a vertical direction.