Geotextile–drainage grid combo earns praise

A new research report cites geotextiles in conjunction with a drainage grid surpass traditional gravel drainage for irrigation, water use, turf health

Research was recently completed at Texas A&M University to analyze the widely accepted United States Golf Association (USGA) recommendations for physical properties of root zone mixtures when designing a putting green using a geotextile filter fabric atop a drainage grid in place of a standard gravel drainage layer.

Water storage in greens that used geotextiles atop a porous plastic drainage structure (AirDrain geogrid) were compared with water storage in standard USGA designed greens constructed with gravel drainage. Three root zone mixtures were combined with four geotextiles atop the drainage grid and three gravel drainage treatments to cover a large range of possible combinations for construction of putting greens. Each root zone drainage treatment was replicated three times in small test greens. After irrigation that produced drainage, water tensions at the bottom of the root zones of the greens constructed with geotextile atop the drainage grid were, on average, 56mm (2.2in.) water less than those in test greens constructed with gravel

As a consequence of the differences in tensions, about 12mm (~0.5in.) more water was stored in root zones of test greens constructed with geotextile atop the drainage grid compared to those constructed with gravel.

The research was conducted at Texas A&M’s Department of Crop and Soil Sciences, under a jointly sponsored grant from the USGA and Airfield Systems Inc., and published in Crop Science, Vol. 51, May–June 2011