St. Jakob stadium in Basel – channels with new type of artificial turf connection installed
HAURATON drainage solution with large retention volume in the service area
The St. Jakob stadium in Basel was subject to extensive modifications during the Swiss Super League’s summer break. The pitch turf with substrate and the adjoining areas, including the surface drainage, were completely overhauled. New hard-wearing solutions to use for the overhaul work were researched and found. The work was specified by the Swiss landscape architects Bütikofer Schaffrath, who are well known for their work on sports grounds. Together with the HAURATON drainage specialists and the Polytan experts on artificial turf they developed and successfully implemented new technical solutions especially for the service ring.
The home stadium of the Swiss football champion has been nicknamed a ‘witche’s cauldron’. This is because in the Basel stadium the spectators are impressively close to the pitch. Only a narrow safety and service area separates the two areas. It is this narrow strip of about two to three metres width where special requirements had to be met.
The special requirements
One of the challenges for the surface drainage was the limited connection to the sewer network. All water accumulating from the service ring is conducted into the sewer at a single point. This represents a bottleneck that requires a special drainage solution which can reliably cope with heavy rainfall events. In addition, both clients and architects agreed to widen the safety area from three to four metres in order to meet the longer term requirements by FIFA and UEFA without having to carry out further conversion work in the future. Furthermore, a solution was wanted that avoids the need to frequently replace the turf in areas exposed to heavy wear. A typical example is the area in the coaching zone, which is exposed to heavy wear. An aggravating circumstance is the fact that these areas in the stadium suffer from poor daylight conditions so that the lawn does not grow very vigorously. After taking all requirements into consideration, the following solution was implemented: the surface in the safety area and on the service ring consists of hard-wearing artificial turf, which is connected to the heavy-duty drainage channel using a special connection method.
Strong channels for reliable and durable service
Once the substrate had been prepared, FASERFIX SUPER channels by HAURATON were installed around the pitch. These channels are extremely strong and robust. In this case, the channel bases used had ductile iron angle housings. In combination with the matching GUGI ductile iron mesh gratings these channels are now suitable for vehicular traffic up to load class E 600. This ensures that even heavy commercial vehicles can drive on these areas without causing damage, something that may be required for the installation of a stage for a concert. This solution takes into account the wishes of the clients, FC Basel 1893 AG, and the St. Jakob-Park stadium association. The briefing called for high-quality products with a durable and reliable service life that would ensure trouble-free service for many years to come.
Large retention volume is able to retain precipitation water
The direct connection to the channels in the service ring is an asphalt covering. The artificial turf has been laid on that basis. The turf meets the grating exactly and finishes at the same level, forming a continuous surface. The briefing called for the grating of the channels to have a stop edge for the artificial turf to abut to. This is to ensure that the turf covering remains securely in place. With the help of a special construction the gratings were positioned just above the top edge of the angle housing and securely fastened. This created a gap between the grating and the top edge of the angle housing.
In the case of heavy rainfall events the storm water can now flow into the channel directly at the artificial turf surface. However, there is also a second drainage level to deal with that scenario. Any surface water that has infiltrated the turf down to the asphalt layer can also run into the channel, without any threshold, and be drained through the gap described above.
For a sports facility the chosen channel size is enormous. The installation was carried out with channels with a nominal width of 300. In this way, Landscape Architect Marc Schaffrath has created a substantial retention volume. In the case of heavy rainfall events the water can be collected and retained in the large channel volume. That is necessary because the sewer connection only has a limited discharge capacity. In that way, the collected water can be discharged into the sewer over a longer period of time without the risk of any flooding of the service ring or the safety area.
“In such a building, safety is of paramount importance. Top quality and a long reliable service life are mandatory.” These are the final comments by Landscape Architect Marc Schaffrath on this project: “In view of the very short time frame available for the work during the summer break, the design coordination has to work very swiftly and informally. Together with René Keusch as the person responsible for HAURATON channels at SFS (HAURATON exclusive distributor in Switzerland for more than 20 years)
– and his reliable advice – the project was successfully completed.“
Natural turf where it is needed
During the overhaul, the substrate of the turf for the pitch was completely renewed. As before, natural turf was chosen for the pitch. The new pitch turf now has again the water permeability required for reliable use as a football pitch. Any water collected from the pitch does not flow into the sewer system but is discharged directly into an open watercourse. This combination of natural turf, drainage solution and artificial turf is a new method that makes it possible to manage sports pitches with less maintenance and hence more cost efficient. This arrangement will create a benchmark for future stadium buildings.