"They asked me to do this because I was the closest to retirement," quipped Dr. A.J. Powell as he began his presentation last January at the Sports Turf Managers Association's (STMA) Annual Conference in Phoenix, AZ.
Powell, a turfgrass agronomist with the University of Kentucky, had the unenviable task of presenting "Natural vs. Synthetic Fields: Comparing the Costs" to a conference room packed with athletic field managers from all over the country. His half-hour presentation covered the many complexities and nuances of the natural turf vs. synthetic turf debate.
Powell has kindly permitted Athletic Turf News to republish the guts of his presentation: four tables setting forth cost and use estimates for sand-based, natural-soil-based and synthetic-based football fields. Powell based his estimates on averages supplied by sports turf managers who are currently maintaining these types of fields.
As an agronomist, Powell frankly confessed his bias towards natural turf. It is his opinion that the driver behind the trend to synthetic infill surfaces is aesthetics rather than player preference, player safety or cost.
"Player safety is often used as a selling point for the synthetic infills, but a worn, even muddy (natural turf) field has never been proven unsafe," Powell maintained. "They may be unattractive and slow, but both teams play upon the same surface and that is part of the game."
Powell asserted it is the over use of natural turf fields in schools, colleges and parks, combined with a lack of investment in turf maintenance, that renders many fields unattractive.
"The fact is, we have never been able to manage grass that would take the kind of wear we now want to give it," Powell admitted. "And very few sand-based surfaces have been a success. It's easy to sell synthetic turf when the experience with sand-based turf has been so costly. They were no better than natural-soil fields. This created a backlash."
Powell was careful to include caveats about the generalizations he had to make to analyze the data. He pointed out that turfgrass maintenance costs vary not only due to different climatic regions, but also due to the difference between expectations and resources available at high school, public park and college fields.
Powell's general conclusions:
Synthetic infill systems can handle up to six times more traffic than natural turf fields in high-use situations
Synthetic infill systems are less expensive to construct and maintain than sand-based fields; but they are much more expensive than soil-based fields.
An existing sand-based field will be less expensive to maintain over a period of 10 years, than constructing and maintaining a new synthetic field that will need to be replaced at the end of that period.
Existing soil-based fields are the least expensive of all to establish and maintain.
"Basic Installation" vs "High-end Installation"
ATN asked Dr. Powell what the difference was between a "basic installation" and a "high-end installation." He replied that a precise definition is difficult to come by, but, in general, the main difference has to do with the kind of base and drainage chosen:
High-end: USGA-type gravel blanket with slit drains
Basic: Slit drains outside the side lines
"But the difference also relates to site preparation," Powell added. "On the college or pro level they must remove a current system out of the stadium or remove a lot of soil. Earth moving is expensive."
On an infill system, the difference between basic and high-end also relates to the following:
how lines are installed: sewed vs. glued;
how many lines;
the quality of the fibers and backing;
whether (and what kind of) pad is used under the carpet;
using some sand in the infill vs. all crumb rubber (which is more expensive);
the size of the area to be carpeted (most high end stadiums include everything within the stadium).
Powell said there are also differences related to regional and local considerations and even the type of facility and its economic backing.
"There are many ways to control costs, which is why we so desperately need a good set of specs for the infills as well as sand based fields," Powell said.
Powell said it makes sense to consider a synthetic infill system under the following conditions:
A landlocked campus that can't build new fields so it has to transport classes and teams off site
Municipal stadiums that host numerous teams, little league events, bands, concerts, etc.
Campuses that hold summer camps and exhibition games at their stadium
Campuses that need an all-weather practice field
Campuses that need indoor playing surfaces that have grass-like qualities.
Under the following conditions, Powell would not recommend a synthetic infill system:
To replace a natural turf field for aesthetic reasons just because it is worn out at the center at the end of the season;
To replace a soil-based grass field in search of lower maintenance costs. In Powell's opinion, it will take dozens of years to make this option pay and the infill system field will need replacement in eight to 10 years.
"Purchasing an infill system makes no sense if you have a natural-soil field that is is showing some wear, but is still repairable before the next playing season. It especially makes no sense if you are spending nothing on maintaining the natural soil field," said Powell.
In closing, Powell called for more independent research on both sand-based fields and synthetic infill-based systems.
Dr. A.J. Powell, University of Kentucky
"Synthetic infill systems are here to stay and they are serving an important clientele, our kids," Powell said. "There are many unanswered questions but there is little or no research and few evaluations reported by independent testing companies and consultants. ... STMA is committed to publishing or otherwise reproducing such findings to its members and the public. Every sports turf professional has a responsibility to stay current with sports field management technology and practices."
In crafting this summary, ATN's editors consulted their notes of Dr. Powell's presentation and also his follow-up, feature-length article "Synthetic Infill Turf vs. Natural Grass," STMA E-Digest, February 2005 which is available online to STMA members.
Both at the podium and in that article, Powell acknowledged the many sports field managers and professionals who contributed to his presentation. He especially thanks:
Mike Andresen, CSFM, Iowa State University
Aaron Boggs, University of Louisville
Jeffrey Bruce, Jeffrey L. Bruce & company
Bob Campbell, CSFM, University of Tennessee
Darian Daily, Paul Brown Stadium (Cincinnati Bengals)
