Protecting the Bunker With Sand Guard
Golf is unlike most other sports in that it does not involve a standard playing field or arena. Instead, golf utilizes the landscape and for that reason forms an intimate relationship with the environment. This relationship between golf courses and the environment has become a priority in the golf industry, according to “An Environmental Approach To Golf Course Development” published by the American Society of Golf Course Architects.
For today’s golf course architects and designers, drainage, as well as, the proper use, protection and conservation of water resources are top environmental considerations.
Although drainage is important in the overall design, construction and maintenance of a golf course, when it comes to bunkers (sand traps) nothing is more important than drainage, according to Jerry Lemons, Senior Design Associate with Lee Trevino Golf Designs cited in Golf Course Management Magazine.
The use of liners under bunker sand has grown along with the demand for better playing conditions, he said.
Working with golf courses and clubs in designing cart paths and developing other areas of the course several years ago, Michigan-based Porous Pave, Inc., realized that its flagship paving surface—porous pavement– made from recycled tire rubber, stone aggregate and a proprietary binding agent could also be used to produce a permeable and flexible bunker lining material that would improve playability and address drainage challenges in course maintenance.
The company launched the Sand Guard Bunker Lining System in mid-2015 with its initial bunker liner installation at Treetops Golf Resort in Gaylord, Michigan. The installation caught the attention of A. John Harvey, a veteran on golf course architect and Michigan resident.
“Having worked with a cross spectrum of leading bunker liner materials and vendors in the golf market on course renovation projects, I was intrigued by this rubber-rock and binder liner solution,” Harvey said. “The interesting thing that struck me was that the material composition included chips from scrap tires and that it was installed as a monolithic, seamless, poured-in-place bunker liner solution,” he said.
The rubber chips, stone aggregate and proprietary binder formulation used in Sand Guard is light weight, approx. 4.3 lbs. per square foot at 1” depth, which is about one-quarter of the weight when compared to other leading bunker liners on the market.
Golf course maintenance crews and golf course contractors can be trained to install the liner material using simple equipment and common hand tools. A trained crew of 5 people can install roughly 5,000 – 7,000 SF/day when proficient at the process.
According to Porous Pave, Sand Guard can be installed during a bunker renovation project or as part of new course construction.
Sand Guard’s rubberized, elastic, mixed-on-site capability makes it a uniquely viable liner material that eliminates reliance on aggregate and concrete plants to supply the material and reduces heavy truck traffic on the golf course property, Harvey said.
Sand Guard has a void space of 27 percent and drains 5,800 gallons per hour per square foot, or 9,300 inches per hour of rainwater. The rubber content in the mix, allows the Sand Guard liner to flex under freeze/thaw conditions or when expansive soils are in the substrate, while maintaining its intended form without diminishing the liner’s effectiveness and function. It fully cures in 24-hours and is ready for bunker sand installation and play thereafter.
A liner’s primary purpose is to protect and prolong the life of the sand and reduce washout. Using bunker liners at the bottom of the sand along the subfloor further protects the sand. Sand Guard excels in this, Harvey said.
Like sand paper, Sand Guard‘s coarse “toothy” surface finish formed by the combined rubber and aggregate mix, helps keep the sand in place and reduces washouts from storm events. It reduces bunker sand contamination from subsoils and drainage stone, while decreasing man-hours needed for bunker sand maintenance after heavy downpours, providing a great return on investment. If, in the future, bunkers need to be extended or added onto for any reason, a new portion of Sand Guard material can easily be poured abutting to an existing section of liner.
While hand raking the bunker sand is the preferred method for sand maintenance, mechanical bunker raking machines can be used when using leaf rake attachments and not cultivating the sand, Harvey said.
The depth of installing bunker sand over Sand Guard is recommended to be in the range of 4-7” compacted, based on a variety of factors. In all cases, periodic and consistent probing and monitoring the depth of sand is important for any lining system so that proper depths are maintained throughout the bunker feature, based on design and maintenance goals and to not disturb the liner material. Another benefit of the rubber’s resiliency or cushion capability is that if a golfer were to hit Sand Guard liner with its club while playing a shot, damage to the club is virtually non-existent.
Porous Pave is always looking into ways to improve its market share in the landscape and golf business communities. Recently, the company has been monitoring research into the use tire derived aggregate (TDA) in the gravel layer of golf course greens that has shown that rubber chips in the drainage layer of the green can reduce nitrate leaching due to the attachment of microbes to rubber particles and the microbial consumption of the nitrates.
© Scrap Tire News, February 2021