The club were having problems with the drainage on their stadium pitch and a detailed investigation was requested.
The cross-fall gradient was found to be inadequate to promote satisfactory surface water movement to slit drains. Infiltration rate measured was poor – there was accumulation of organic matter in the upper part of the topsoil and evidence of black layer that had developed following water-logging. In addition, it was found on examination that there was not proper contact between the slit and lateral drains in the few excavations carried out – and there was unsatisfactory flow to the drainage outfall. Grass cover was dominantly annual meadow grass – and being shallow-rooted it would be subject to tearing following scrumming.
Records kept were not conclusive. It was recommended that ideally the pitch should be re-graded. Cost-effectively it would be worth creating a camber with satisfactory fall in gradient to the sides.
Slit drains would have to be re-installed once the lateral drain installation had been properly checked and found to be satisfactory. Regular sand dressings would be vital to maintain uncontaminated access of water run-off to the slit drains – and furthermore, annual renovation should ensure a dominance of deep-rooted ryegrass is established after satisfactory removal of most of the meadow grass.