Why is olympic field hockey field wet?

Answer 1

An infill is used on an artificial hockey turf to help keep the pile upright and decrease wear and tear on the carpet. Water is used as an infill at national and international levels, as it allows more consistancy in ball roll and bounce, free movement of the pile, and more shock absorbance and less abrasiveness than earlier sand-based turfs. Sand-based or hybrid turfs are still used at local and regional levels because water-baesd turfs are more expensive to install and maintain.
London 2012 will be the first world event to be played on a different coloured synthetic turf to the traditional green.

The water-based surface uses a high-performance polyethylene resin helping to make it the world's fastest pitch.