Now that the 35 – 40 centimetre-deep drainage trenches have been dug on Hole One of the Old Course, this week gravel or crushed stone will be placed under, around and over the drain lines. The trenches will then be “… backfilled with a porous, sandy soil to the exiting surface grade,” states Andrés Sánchez Garcia, General Director of Atalaya Golf & Country Club.

According to Sánchez, coarse sand is the ideal material to use to backfill drains “… located in depressions and waterways where large volumes of water must be accommodated by downward percolation to the subsurface drains”.

“Drainage systems normally consist of one or more mainline drains with a series of evenly spaced laterals extending across the fairway as dictated by the topography (herringbone system),” states Sánchez.

Different types of drain lines are available, including perforated, flexible plastic and rigid PVC pipe. “Perforated plastic is the most widely used due to the ease of installation,” says Sánchez.

FYI: The photo above shows a flexible PVC drainage tube laid in a bed of gravel. 

Sánchez comments that the drainage tube will later be completely surrounded with gravel. The trench will then be filled with coarse sand. In a few months, the trench will be covered with Bermuda grass.