The Site
- Prone to waterlogging after heavy rain, resulting in last minute cancellations, disruption to schedules and loss of revenue.
- Varying soil depth 50mm-200mm.
- Varying depths of poor quality sand 50mm-350mm.
- Layer of large boulders under pitch, some just under the surface.
- Bedrock at invert level of main drain on one side.
- Ingress of water from car parks and terraces.
- Very poor grades ie.pitch is nearly level, no natural water movement on surface.
The Brief
- Drain and improve the pitch surface without major reconstruction and the accompanying disruption and extended pitch closure.
- Formulate and implement a maintenance program.
The Challenge
- Limited window of opportunity to execute the works, 3 weeks
- Underlying boulders made the excavation of drains difficult.
- Lack of surface grade to encourage movement of water.
- All excavated material (550m3 ie.55 truckloads) had to be exported off site on an on-going basis in a city environment.
The Solution
- Perimeter drain along both sides and across one end laid to a grade going to an outfall. Lateral drains at 5 metre centres laid to a grade from the main drains on either side to the centre of the pitch.
- Sand slits at 1 metre centres laid along the length of the pitch.
- Implementation of an intensive maintenance program including sanding, vertidraining, overseeding and fertilising.
Implementation of Plan
- Main drain was dug to a grade around pitch edge using an excavator and rock breaker where necessary.
- Lateral drains were laid to a grade at 5 metre centres from both sides to the centre of the pitch using a suitably modified trencher to cut through the boulders.
- Gravel and pipe were laid simultaneously thus ensuring that as the underlying ground conditions changed from deep poor quality sand to boulders and back again the grade on the pipe remained constant.
- Sand slits were installed at 1 metre centres along the length of the pitch.
- All lateral drains and sand slits were capped with a layer of USGA spec sand.
- Main drains were capped with selected topsoil and reseeded.
- Provision was made where necessary to divert runoff from car parks and terraces directly into the main drain
- The pitch was vertidrained, top dressed intensively with USGA spec sand, overseeded and fertilised.
The Result
- A professionally prepared maintenance plan was drawn up and is being strictly adhered to.
- The pitch is now playable the whole year around and is requested by players and management alike.
- A return was got on the investment as soon as the pitch was reopened and has continued since.
Main Drains (mtr)
+
Lateral Drains (mtr)
Sand Slits (mtr)
Delivered on Time (days)