By Kevin Earley
From the June 2023 Issue
At one time, the 158 acres of land on secluded Highway 30A in the Florida Panhandle were just pure scrub oak, sand, and blue water. But in the late 1970s, Jim Stephens, his wife, Julie, and his father, Elton, purchased the land with a vision to develop a community dedicated to architectural excellence and a deep respect for the natural environment. In 2004, that vision finally came to fruition in Alys Beach, an unincorporated planned community that created the first true permeable road installation in the Panhandle. Nearly twenty years later, the community continues to grow and so too, does the permeable road system.
Under-Street Utility Access
Named for Stephens’ mother and located in Walton County, Alys Beach was designed in a New Urbanist style, a European, very pedestrian-oriented design. Designers accomplished this style with a Florida spirit by combining Bermudan architecture with alley and courtyard living and a high-end, old colonial aesthetic. The whole town is constructed of masonry and white stucco which reflects light—a sustainable feature. There also are white concrete roof tiles and wood accents.
A more challenging aspect of New Urbanist design is that it calls for utilities to be located under the street. “Two things we knew right away were that it rains a lot there, and the utilities would be accessed regularly as the town continued to grow,” explains town architect MarieAnne Khoury-Vogt. “If we were to put in asphalt, pieces would be cut out and replaced every time the utilities needed to be accessed, creating a terrible patchwork. Asphalt also just did not meet the aesthetic or sustainability goals for the town.”
The team came across Belgian Cobble® permeable paving, a dark gray blend color with a granite-like appearance from Belgard, and decided it not only fi t perfectly with the aesthetic, but the need to access utilities without leaving evidence of disturbance. “You can just pop the pavers out to do what is needed with utilities and then put them back in place and no one ever knows they were disturbed,” says Khoury-Vogt. “I can’t tell you how many times this has been done since the road was first laid. The installers work very quickly.”
In addition to the issue of access to utilities, the roadway was a key focus of design and planning because of its potential impact on the environment. “This was a legacy project for the family members, who were adamant from the beginning that sustainability be one of the key components of the development,” says Jim Martelli, civil engineer and managing director, Innerlight Engineering Corporation. He has worked with Alys Beach since 2002. “They wanted the neighborhood to stand the test of time and be the best it could be for the environment. A significant part of that is stormwater management.”
“They wanted the neighborhood to stand the test of time and be the best it could be for the environment. A significant part of that is stormwater management.”
— Jim Martelli, Innerlight Engineering
Martelli looked at the site conditions. Located in the Panhandle, the site is low and wet and the groundwater is high. What is unique about Highway 30A, and particularly Alys Beach, is that it ranges from 26′ to 35′ above sea level and is all beachfront property. It shoots up 25′ immediately from the Gulf of Mexico to form a tabletop, then undulates through about 158 acres of neighborhood. Additionally, there are approximately 20.5 acres of jurisdictional wetland on the very North side.
“What’s cool about the soils is that they are truly beach sand, a very coarse permeable sand,” says Martelli, noting sustainable development means you have to treat stormwater runoff as close to the source as possible. He continues, “It was determined that this great sandy soil would let us utilize what Nature provided, so we put the stormwater system under the road and the road is allowed to be part of the system itself. This permeable road concept was the first in the Panhandle when we began using it in 2004, and maybe even in the Southeast, because you need the right soils to pull it off.”
He and Robert Reeder, owner of Stone Scapes, Inc., developed the permeable road system together. The road base was a key element to consider. “Typically in a cobblestone roadway, this would include a crushed concrete aggregate base, but there is no permeable benefit to that. The solution was to use a different base material, washed #57 stone,” says Martelli. The #57 is similar to river rock but there are a lot of angular pieces that lock together, which is beneficial for a base.
Additionally, nearly half of the base consists of air (the space that naturally occurs between rocks), which provides plenty of space for the water to be stored until it infiltrates into the underlying soil. “Given this, the road base also provides some storage for stormwater runoff.” Martelli calculated that 12″ thickness of the #57 stone was suitable to support the anticipated heavy vehicle loads. In addition, the Belgian Cobble is 2 3/4″ thick, helping to achieve the vehicle loading requirement. “We knew if we could come up with a design that would support vehicle loads and infiltrate rainwater we had a multi-purpose pavement system,” says Martelli.
Martelli and Reeder chose to use a nominally 1-1/2″ thick bedding layer of angular chip gravel, known as #89 stone, under the Belgian Cobble paver and to fill the joints. “Rainfall is absorbed almost immediately into the ground, getting filtered in the process,” Martelli says. “Belgian Cobble with washed open-graded aggregate is a great permeable solution because of the width of joints,” adds Reeder. “…we’ve never seen water standing on the roads in the nearly 20 years it’s been there.”
Permeable pavers are gaining popularity due to rising municipal stormwater management concerns resulting in more stringent regulations. Read more…
The permeable road system began installation in 2004 and roads were laid before the buildings were constructed. As a result, heavy construction vehicles regularly traveled on the pavers. “It took me by surprise the first day on the job when I walked on them and they moved. I wasn’t sure how they were going to stand up to the traffic they would see,” says Reeder. “I was really impressed when we swept in the 89 stone into the joint openings and the pavers were firmly in place. They have withstood the test of time and heavy traffic and still look good.”
Today, the roadway is continually added to as the community expands and sections are replaced following utility work. Approximately 900,000 square feet of Belgian Cobble to date. “Our first use of the Belgard Belgian Cobble in Alys Beach was the first time we ever laid these pavers,” says Reeder. “They have to be laid by hand because they are not interlocking and come in seven different sizes.”
The permeable road system has helped Alys Beach convey the aesthetic KVA designed for the community while achieving the family’s sustainability goals.
“People regularly bike, walk, skate or push strollers along these alleyways. It all works,” says Khoury-Vogt. “To see it, many people think it looks like a town in Greece or other Mediterranean cities.”
Earley is director, Commercial Hardscapes at Oldcastle APG a CRH Company. Earley is also a LEED Green Associate and a contributor to the American Society of Civil Engineer’s Permeable Pavement Manual and current permeable paver design standards, and is active in technical leadership roles for the Interlocking Concrete Pavement Institute. He has over 25 years of experience related to concrete products used for environmental site solutions. For more information, visit www.belgardcommercial.com.
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