Protecting the hallowed turf

Specialised turf protection systems allow venue managers to increase revenue by hosting concerts without disrupting the sporting schedule

When the Beatles opened their North American tour at Shea Stadium in New York to an audience of 55,600 people on 15 August 1965, it was more than a milestone in rock and roll history. The first ever stadium concert suddenly expanded the possibilities for attendance and revenue generation for outdoor sports venues.

Crowds standing on a specialised flooring
solution at Suncorp Stadium in Brisbane

It also meant the beginning of a nightmare for turf management. Before the advent of specialised turf protection systems, venue managers were forced to use tarpaulins and other roll-out materials. Such methods offered limited protection.

In the event of anything more than moderate rain, the weight of tens of thousands of pairs of feet would squash the surface down, eradicating the level surface of the pitch. The inevitable outcome was that the pitch would have to be completely re-laid with turf before any sporting events could be held.

Developing a solution
This organisational nightmare for venue managers continued right through the 1970s and 1980s, during which period stadium gigs continued to rise in popularity. Venue managers couldn’t turn down the opportunity to increase revenue, but risked ruining their pitches in the process.

The event that marked the beginning of a new era for turf protection was a concert on 16th June 1991 at Wembley Stadium, starring British singer Rod Stewart. A company called Terraplas had provided a unique flooring system that covered the turf without damaging it, despite the movement of 70,000 eager fans.

The turf covering had been in development for some time, including two years of testing for effectiveness, health and safety and fire risk. Some of these trials took place at Wembley.

Robert Else, chairman of Terraplas says: “It wasn’t just a matter of whether it would protect the turf and leave good grass when we took it off. It was a case of whether it would do all that and be safe for the patrons and whether it would be accepted by Brent Council, the licensing authority for Wembley Stadium and one of the strictest licensing authorities in the world. If you can satisfy Brent Council, you can satisfy anybody!”

Climate control
The turf protection system, called Terraplas, consists of a number of interlocked metre square plastic tiles resting on feet. It is the patented incorporation of these feet that creates headroom between the grass and the floor, allowing the blades of grass to stand upright. The only areas where the grass can’t stand up are directly under the feet, which cover a small portion of the turf.

The revenue from a concert can be twice that
of a football match

This design also creates continuous air space between the turf and the crowd, which allows air not just to pass under each square metre but to pass under the whole of the tiling system. As well as aerating the turf, the semi-transparent material allows enough light to pass through for healthy grass growth.

The tiles also control the level of moisture reaching the pitch, doing away with the need to water the pitch while the cover is on. “When the sun is out, moisture is drawn from the soil. That then condenses on the underside of the tile. When the sun goes down, the water goes back down and waters the grass,” Else says.

The tiles are also designed to cope with too much moisture from the elements. “If it has been very hot and humid, when you take it off there will be a little bit of yellowing where the feet have been. All you have to do is leave it for a day, or just cut it, and the yellowing goes. Or if it rains, the water will actually run off to the sides. Very little goes onto the grass.”

Spreading the load
Each of the tiles rests on 17 feet, which are specially designed to prevent an increase of pressure on the grass. About 60mm in diameter, the feet are shaped like the underside of a button – rounded at the edges and containing four holes. “The design doesn’t affect the plant. There are no sharp edges that can cut into the grass.”

The tiles are rigid but flexible. They will take a huge amount of weight, provided it is spread correctly. This is crucial when setting up the entire infrastructure necessary for a major stadium concert. “All the stages, lighting and mixing towers, are built on top of the surface. The steel structures for lighting and the delay towers are very heavy, and mixer towers are getting bigger.” To spread this weight across several tiles, sleepers or scaffold boards are laid down. On top of these lengths of wood the steel structures are built, often with the use of cranes.

One tile can take a great deal of weight, as long as it is spread over the 17 feet. What they can’t take is points of very high pressure – such as those created by the wheels of a fork lift truck, which would push the individual feet into the ground. “A fork lift truck’s point load is a million times higher than a mixer tower. A mixer tower can be a hundred tonnes, but you’re spreading that load over 200 square metres, whereas a forklift has probably got a footprint of 10cm by 10cm, so the point load is hugely higher.”

Other heavy structures include crowd barriers, which now usually consist of two layers. The bar is also typically built on Terraplas – sometimes with a beer tanker, which takes up a large area. “Even with all these structures in place, there is space for 15 to 20,000 people on a football pitch.”

Refining the system
Terraplas now manufactures three different systems for natural turf – Terraplas, Terraflor and Terratile. They all use the same principle, but reflect advances in the efficiency of materials available. “What we are having to do is to engineer design with better, lighter products. If they are lighter, with the cost of raw materials as they are, manufacture is a lot cheaper. We are engineering the design so that it’s just as strong but lighter, and therefore cheaper.”

Advances in polymer technology are helping as well. The flooring is made of structural foam. “If you were to cut through a piece of the plastic you would see bubbles of air. This keeps it lighter and makes it stronger.”

Quick turnaround
Using a specialised turf protection system enables venue managers to schedule sports events soon after the concert is over. “On numerous occasions at Wembley, they have done a concert and held a major game, such as the FA Community Shield, two days later,” Else says.

the new Wembley stadium, we did seven concerts in five weeks. We took the cover off after every concert and put it down before the next one. It was quite a feat, when you consider the thousands of tonnes of equipment that was coming in and out of the venue”.

Typically, the tiles are stored in the stadium’s storage space – Wembley has a huge undercroft beneath the seats. But during this period, because there were so many performances close together, the tiles were placed on the road around the side of the pitch.

Major international events
Since its inception, Terraplas has been used twice at summer Olympic Games – at Barcelona 1992 and Atlanta 1996. It also served the 1998 Commonwealth Games in Kuala Lumpur. “Although everything is manufactured in the UK, we are 90 to 95 per cent export,” Else says.

The flooring system was also used to protect Longchamps race course from the impact of visitors to the Papal visit to Paris in 1997.

The Pope is visiting Sydney in July 2008, at Randwick racecourse. “We are covering the most delicate areas. We are expecting half a million people,” Else says.

For a venue manager, systems such as Terraplas mean that a stadium can generate significant revenue from events other than its core sporting use, without damaging the property. “The risk is minimal. The likely revenue from a concert is around double what you’d expect from a sporting event.”