Mole drainage as an alternative to sand slitting in natural turf sports surfaces on clays

The drainage of sports surfaces of natural turf is essential for increasing access to sports facilities and to increase participation. Commonly, these surfaces are situated on soils of low hydraulic conductivity, which require the installation of remedial drainage to bypass the flow of water from the surface to an outfall. This is usually achieved with sand slit drainage, which is costly. A number of these soils are suitable for mole drainage at a much lower cost. Using an actual football pitch in a field‐scale experiment on a smectitic, calcareous clay, this study determined that mole drainage was effective in reducing soil moisture content at 100‐mm depth, but the reduction was not as great as sand slit drainage in the first year after installation. Despite peak soil moisture deficits of 101 and 157 mm in 2005 and 2006, mole leg‐slots did not re‐open in the 2 years following installation. There was significant slumping of the sand slits, however, because of soil shrinkage. This prevented play on the sand slit area to safeguard players.