Parking lots and roads are notorious for sheet flow stormwater runoff. The problem is twofold, first stormwater is diverted from infiltrating the earth in the groundwater as God intended so as to recharge underground aquifer. And second, as it runs off roads and parking lots it collects contaminants and byproducts of vehicular traffic such as nutrients, trace metals, oil and grease, all of which can include harmful elements such as nitrates and orthophosphates. These pollutants concentrate in storm drains and eventually make their way into bodies of water such as our Chesapeake Bay. Once there, the nitrates & orhthophosphates become food sources for algal blooms which are the first step in the eutrophication.

So what is eutrophication? H.W. Art, defined it as “The process by which a body of water acquires a high concentration of nutrients, especially phosphates and nitrates. These typically promote excessive growth of algae. As the algae die and decompose, high levels of organic matter and the decomposing organisms deplete the water of available oxygen, causing the death of other organisms, such as fish. Eutrophication is a natural, slow-aging process for a water body, but human activity greatly speeds up the process.”

To alleviate this problem, the EPA & the Clean Water Act now require states to adopt total maximum daily load (TMDL) limits as the basis of their water quality improvement. So in one effort to reduce eutrophication among other things, many Architects and Municipalities are choosing to pave sidewalks, trails and parking spaces with Flexi-Pave. Passive Treatment Technologies (PTT), such as Flexi-Pave, provide a cost effective solution for the removal of nutrients from storm water, while saving energy, to reduce nutrient pollution. In fact, a long term water quality study conducted in 2010 by a Civil Engineering & Environmental Firm showed an amazing 83% reduction in nitrates and an 88% reduction in phosphates from contaminated water flowing through Flexi-Pave.

One recent project using Flexi-Pave for this purpose was at Ben Brenman Park in the City of Alexandria, VA where a strip of parallel parking spaces near the baseball fields were installed in 2012. The parking spaces provide 16-20 additional parking spaces and also filter the stormwater runoff from the main roadway. Reviews by city officials and residents have been overwhelmingly positive, so that several additional Flexi-Pave projects are currently in the works for the City of Alexandria.

Ben Brenman Park Parallel Parking Site Plan

Ben Brenman Park Parallel Parking Spaces

35 photos

Capitol Flexi-Pave took on a bridge re-surfacing project for the Country Club at Woodmore in August, 2012. Rotting wood on the main bridge leading to the golf course posed a safety risk to walkers, and after unsuccessfully attempting repairs using several other re-surfacing solutions the Club found out about the Flexi-Pave product. The Club’s Golf Course Operations team was convinced that the product’s environmentally friendly porous surface was perfect for the job. The project was completed in one day, and the Club’s Golf Course Operations Superintendent was excited about the result. Take a moment to read the blog post he wrote on the project.  Another article about the bridge was posted here.

Woodmore Country Club Bridge Overlaty

14 photos

When this skatepark plans were in Design Development phase the “off-limits” areas of the park were spec’d as planting beds with shrubs and mulch. But as the plans were finalized during the Construction Documents phase, it became evident that the beds would become a receptacle for trash and the mulch would most surely be spread throughout the skatepark. Another solution was needed, one that permitted stormwater infiltration but was low maintenance and durable. Flexi-pave was chosen to be used in these areas instead. Since installation, one side of the park has performed well, but the other side with it’s adjacent skateboard ramps proved to be a challenge. The evening of the pour while the material was still curing, skaters climbed over the barricades and skated on top of the wet surface causing damage. Since then, additional damage has been done from the extreme jumps and tricks being performed by the skaters. After an investigation, we determined that the skateboard wheels, when landing on the paving with a rider after a jump, were exceeding the approved PSI limits for Flexi-Pave. Lesson learned, installations adjacent to jumps is not recommended.

To view the plans of this project click on the following: Wakefield Skate Park Plans

Wakefield Skatepark Medians

31 photos

In the Strawberry Run stream restoration project the City of Alexandria restored the stream to prevent flooding and stream erosion. The work also improved habitat, improved water quality and protected aquatic life. Part of the city’s best management practice to improve the Cameron Run Watershed, and subsequently the Potomac River and eventually the Chesapeake Bay, was to include pervious paving as part of their multifaceted approach. So when a trail was needed to join the city sidewalk to a bridge crossing the stream, Flexi-Pave was selected over pervious concrete or pervious asphalt to protect the delicate Resource Protection Area.

Cameron Run Watershed Trail Plans

Taft Ave Trail

20 photos

In Silver Spring, MD just a few blocks from the headquarters of the Maryland-National Capital Park & Planning Commission (M-NCPPC), Montgomery County’s premier regulatory agency who oversees land development & tree protection, a project was in development for many years. There were several high profile mature trees on the parcel that the county insisted must be protected. An extensive Tree Protection Plan was developed by the Architect and Urban Forester / Arborist which incorporated the trees into the design. As a result, special measures were taken to minimize any impacts to the trees before, during and after construction. One part of the plan, the pocket parks within the tree protection areas, called for trails. The Architect at the time didn’t know about Flexi-Pave, so he specified pea gravel paths around the trees. On paper this seemed like a perfect solution. But in reality, the residents loathed the pea gravel. It spilled out of the edging, got in their shoes, rutted when they walked in it and so the HOA began to look for another solution. The challenge was that the M-NCPPC would only accept a tree friendly, non-invasive pavement in the tree protection areas. Pervious concrete and pervious asphalt were possible options, but they required extensive maintenance and vacuuming because they tend to fill up with fines over time and become impervious. Enter Flexi-pave, a product that eliminates the shortcomings of the other pervious pavements. When the HOA found out that Flexi-pave required NO vacuuming because it’s dynamic voids allowed sediment to pass through, they presented the option to M-NCPPC. Staff Arborists and planners at the county agency evaluated Flexi-pave’s claims and determined that it was a product that could be endorsed and would accept. In one official’s own words, “Unlike pervious concrete which we know will eventually become impervious, we consider Flexi-pave to be invisible as far as stormwater is concerned.” So since Flexi-Pave didn’t inhibit air or water infiltration to the tree roots, it was approved and installed around the tree high profile trees. Since completion, the HOA residences have applauded the new paving surface and the parks are used more frequently now.

Woodside Courts Pocket Park Trails

13 photos

When a Montgomery County, MD Erosion and Sediment Control inspector bought his home in Damascus, the first rain event brought an unexpected surprise. The driveway sloped down to the garage and during rain events, the sheet flow of water flowed right into the garage, flooding it. It was clear that the driveway had not been well thought out. And ironically, after citing contractors over the years for not controlling their own stormwater runoff, he had his own runoff problem to deal with. In his search for a solution, he found out about Flexi-pave’s unique properties as a heavy duty paving material that was porous to the rate of over 2500 gallons per square foot per hour. And after considering the many options, he decided that a Flexi-pave diffusion strip was the most cost effective solution for his problem. So a strip of driveway was saw-cut and removed and replaced by Flexi-pave leading to a drain line. The first rain event after the installation was proof that the system worked. He has had no additional flooding since the installation.

Residential Driveway Diffusion Strip

24 photos

Zuckerman Gravely Management Inc. manages many numerous properties around the National Capital Region and one of their recurring challenges has been failing tree surrounds.  Whether they consist of bare soil, granite cobblestone, bricks, metal grates, overgrown grass or rubber panels, they all fail eventually and become tripping hazards for pedestrians.  Zuckerman must ensure that their properties are ADA compliant and thereby eliminate these trip/fall hazards.  Once Zuckerman execs realized the benefits of Flexi-Pave, they began replacing failing tree surrounds on their properties with this poured-in-place rubber & stone mixture that remains a porous, non-slip, non-cracking and ADA compliant surface.

Phase 1 of the work at the Potomac Place Shopping Center was to replace the tree surrounds in the courtyard where a Starbucks and several restaurants have outdoor seating under the shade trees.  The installation took 1 day and comments from the affected business and patrons have been overwhelming positive.  In addition, the seating area which was limited before due to the soil mounded around the trees has now been increased as chairs and tables can be positioned directly on top of the tree surrounds without compacting the soil or harming the trees.

Potomac Place Shopping Center Tree Surrounds Phase 1

30 photos

In an effort to display their environmental awareness, Firestone’s corporate officers mandated that all new Firestone stores will include green technologies such as pervious paving. So this store in Egg Harbor, NJ received it’s Flexi-Pave sidewalk in May of 2012.

Egg Harbor Firestone Sidewalk

19 photos

After Arlington County asked Capitol Flexi-Pave to host a Lunch & Learn with county officials to inform them about Flexi-Pave and it’s many uses, county staff realized that traditional areas like the concrete pads under Capital Bikeshare locations didn’t need to be impervious.  So the next two Bikeshare locations scheduled to be installed in Arlington specified Flexi-Pave to be used in lieu of concrete.  Capitol Flexi-Pave coordinated with the Arlington County maintenance staff for division of labor.  The county staff prepped the bases and Capitol Flexi-Pave staff  poured the Flexi-Pave.  These two installations served as test locations to evaluate the product’s durability before the Arlington County began spec’ing Flexi-Pave on a widespread basis throughout the county.  This particular Capital Bikeshare is at N. Fairfax Dr & Wilson Blvd.

Capital Bikeshare #2 Plans

Capital Bikeshare 2

13 photos

After Arlington County asked Capitol Flexi-Pave to host a Lunch & Learn with county officials to inform them about Flexi-Pave and it’s many uses, county staff realized that traditional areas like the concrete pads under Capital Bikeshare locations didn’t need to be impervious.  So the next two Bikeshare locations scheduled to be installed in Arlington specified Flexi-Pave to be used in lieu of concrete.  Capitol Flexi-Pave coordinated with the Arlington County maintenance staff for division of labor.  The county staff prepped the bases and Capitol Flexi-Pave staff  poured the Flexi-Pave.  These two installations served as test locations to evaluate the product’s durability before the Arlington County began spec’ing Flexi-Pave on a widespread basis throughout the county.
This particular Capital Bikeshare is at N. Veitch St and 20th St N.

Learn more about Bikeshares HERE!

Capital Bikeshare #1 Plans

Capital Bikeshare 1

13 photos