The Great Debate: Synthetic Or Natural Turf
By Neale Stralow and Scott Buttari
What critical project and site conditions do project managers need to consider before specifying synthetic-turf or natural-grass installations on athletic fields? When is synthetic-turf surfacing the best solution? When is it not? Even though two recreational field projects in Florida had diverse requirements and site conditions, both showcase unique field solutions that produced optimal playability, addressed operations and maintenance costs, and responded to local environmental conditions.
Northeast Regional Park in Polk County and Out-of-Door Academy sports fields in Sarasota County are projects where synthetic-turf and natural-grass installations were each the right choice, in view of the individual site conditions.
Soil conditions in Florida differ wildly from region to region—from the high-sandy and extremely drained soils of Northern Central Florida, to the more saturated environments often seen in Southwest Florida. Northeast Regional is situated on a sandy ridge along U.S. Hwy 27 in central Florida and has more than 100 feet of elevation change on the 83-acre property. The Out-of-Door Academy is a 20-acre site with a high water-table elevation surrounded by wetland areas.
Not Enough Water
During the mid-2000s, Polk County Board of County Commissioner’s Parks and Recreation Department (since renamed the Natural Resources Department), began looking for ways to implement the goals outlined in the “Polk Vision” plan. Polk Vision is a 501(c)(3) organization created as a community-led partnership of local governments, private organizations, and individuals working together to develop solutions to the county’s critical future-growth issues. One of the highest ranked needs identified was the creation of a public recreational facility north of Interstate 4 that would serve unincorporated county residents. This is how Northeast Regional Park was born. The project would also become the county’s first public park to feature synthetic-turf athletic fields.
Early in the process, the use of natural grass versus synthetic-turf athletic fields was discussed. The site, located at the furthermost northeast quadrant of the county, was a remnant citrus grove surrounded by rapidly developing residential developments and located within a water-containment designation, indicating limited potable water resources. The site had two 4-inch wells that provided up to 89,000 gallons per day for the citrus grove—definitely not enough to also properly maintain athletic fields. Initial water-use calculations for performance sodded fields identified that the planned six soccer and five baseball fields would require approximately 115,000 gallons per day on average. Additionally, the 85-acre regional park had other programmed elements that would add another 155,000 gallons per day. With the park already leaning towards synthetic turf because of the lack of water, other factors also limited the viability of a natural-turf surface:
Operations and maintenance. There was a concern that natural-grass fields would wear out quickly due to the arid conditions and anticipated high level of use. Using synthetic turf essentially eliminated the water demand that natural grass requires, which is also an ecological incentive.
Playability. Unlike natural grass, synthetic turf can be used in all types of weather, daily, and without the worry of damage. Today’s synthetic turf is designed to simulate the experience of practicing and playing on the best grass fields, which equates to a heightened playing experience.
Revenue generation. If properly and efficiently maintained, the fields’ high playability surfaces and close proximity to Walt Disney World/ESPN’s Wild World of Sports Complex provide the county with excellent field-rental opportunities for traveling teams seeking practice facilities.
Synthetic turf can also help save natural resources and annual operation and maintenance costs in the long run. The average cost of natural grass per square foot is approximately $3, versus approximately $5 for typical-quality synthetic turf1. However, maintenance costs, especially over the long term, tend to be higher for natural-grass fields. Including operations and maintenance costs in the calculations is important, as its initial cost differential can be offset within 3-4 years, per the Synthetic Turf Council. Considering all of these factors, the county decided synthetic turf made the most sense. Ultimately, this 85-acre, $14.5-million park specified more than 81,000 square feet of 2.25-inch pile height, parallel slit-film turf, with a 70:30 mix of cryogenic rubber and silica sand for the soccer fields. Synthetic turf was also specified for the Phase 2 baseball field installations.
But can developing a solution that uses natural grass protect the environment as impressively as synthetic turf? It can, if a creative approach is taken in the design.
Drain Or Flood
More than 90 miles away at Out-of-Door Academy (ODA) in Sarasota, the school administration was working on plans to add a baseball field, eight tennis courts, a softball field, a football/soccer field, and a 400-meter track to the campus. With limited space and very wet soil initially seen as major obstacles, the design team thought creatively and found specific solutions to address the site and specific project needs.
Established in 1924, ODA college-preparatory school is the second-oldest private school in Florida and serves 700 students from Pre-K to 12th grade. Correlating with the ODA’s mission, the school’s Athletics Program also strives for excellence and is a vital component of the school’s spirit. That is why these new athletic fields are so important—their success may affect an athlete’s performance, and ultimately impact opportunities for scouting and recruitment opportunities for collegiate athletics.
ODA’s campus is not only extremely constrained, but the soil is saturated due to its location on Florida’s west coast and the wetland systems surrounding the campus. ODA preferred a natural-grass field, but was intrigued by the nearby Sarasota Polo Club, which features a dual-purpose underdrain/irrigation pipe network. With the spatial constraints on this site, this combination system could be the perfect solution to reduce the need for dedicated stormwater facilities and maximum playability. After much consideration, ODA ultimately decided to design the baseball/multi-use field with a dual-purpose, drainage/irrigation underdrain system and “flat” grading, while the football/soccer field was detailed with a standard crowned field and less underdrain. As with a synthetic-turf system, this field design requires a free-draining, imported soil to allow for a reduced recovery time following significant rain events. As a safeguard and for other maintenance purposes, the baseball field includes a standard above-ground irrigation system, but through the use of an adjustable weir system within the underdrain outfall, the field staff has the ability to drain or “flood” the field based upon recent or expected rainfall.
This unique underdrain system, coupled with natural grass, proved to be the right solution for the project. As with the Northeast Regional Park project, the benefits seen with the use of this design include:
Operations and maintenance. Rainfall and/or irrigation can be held within the underdrain system during drier times to reduce needed irrigation volumes. During the wet season, the adjustable weir can allow for reduced recovery time after a significant rainfall.
Flexibility. Thanks to the “flat” field, the oversized outfield can be easily utilized as practice space by all school teams in a variety of configurations.
Efficient use of land. The fields saved the consumption of 15 to 20 percent of land by using the underdrain system.
This 20-acre project had a construction cost of $4.5 million and was considered a success by the client, community, and students. The natural-grass solution, coupled with an extensive underdrain system typically seen with synthetic turf, was the appropriate solution for this saturated environment.
In the end, when designing athletic fields, there is no “one-size-fits-all” regarding turf. A good designer takes several factors into account before recommending a solution. Location, soil conditions, available land, cost, playability, and operations and maintenance requirements are all important aspects that will dictate the ultimate design. Therefore, the question really isn’t whether to use natural grass or synthetic, but whether to develop a thorough, well-planned design that considers all variables and alternatives, including unique combinations of traditional design that fit the site conditions.
Source:
“Pros & Cons of Artificial Turf in Sports,” The Arizona Central, part of USA Today, Hannah Wahlig. http://healthyliving.azcentral.com/pros-cons-artificial-turf-sports-1388.html
Neale Stralow, PLA, AICP, is a Senior Project Manager for Stantec in Tampa, Fla. Reach him at Neale.stralow@stantec.com.
Scott Buttari, PLA, LEED AP, is a Senior Landscape Architect for Stantec. Reach him at scott.buttari@stantec.com.