Fab Find: Biopaver

Every parking lot, driveway, sidewalk and road is an impervious surface acting as an unbroken barrier between the wet rain falling from the sky and the dry earth below. Water draining from these surfaces gains speed and quickly rolls off all exposed ground. Even minor rains become small scale floods, eroding what little soil is exposed and quickly filling municipal storm systems -- by Joe Hagerman

Increasingly, the amounts of impervious surfaces created within our communities threaten the quality of the receiving waterways. These surfaces increase erosion, the quantity and containments within the water, and the depletion of the recharge to aquifers. With each rainfall, water rushes off an ever increasing expanse of impervious surfaces into a watertight storm water management network of gutters, collectors, and piping under the streets that lead to retention facilities that serve to provide rudimentary treatment of the water. While these treatment systems serve to address the gross elimination of sediment contamination, the majority of the rainwater is discharged directly into receiving water bodies -- untreated and contaminated. Have you ever walked the streets and seen clean water pooling on the ground?

No, but the water you did see, contaminated with petroleum, oils, and industrial soot, easily gets carried into the ground through porous concrete and pervious pavers just as it would easily get carried into the storm system and the receiving stream. Oil and water seek the path of least resistance, like cracks in pavement or joints between pavers.

"Biopaving" is a green solution for storm water management that integrates impervious surfaces and islands of biomitigating and bioremediating plant material; grasses and weeds such as crabgrass. These bio-islands of phytoremediating plants are manufactured into the product and unwrapped by the environment after installation through the biodegradation. Using the plant islands, storm water is taken into the porous soil. The contaminated waters are exposed to the root structure of the biomitigation or bioremediating plants which are attracted to the containments in the water and soil. The roots transport the containments to the plants leaf structure. This action is a natural defense mechanism for plants to ward of insects, birds, and other predators. This process is more commonly known as phytoremediation.

The first product utilizing this technology, the Biopaver, is an innovative interlocking concrete paver with prepackaged soil and phytoremediating planting material, targeting petroleum. The prepackaged soil is compost from a local municipal waste stream and is packaged and molded in a biodegrading bioplastic mold. This mold forms within the concrete paver during manufacturing and is, therefore, installed with the paver. After installation, when the paver is exposed to the elements, the mold and packaging biodegrade and help set the paver into place. It also exposes the heart of the paver, releasing biomitigation and bioremediating plants. These tough plants grown in the rich soil and harvest the containments from the storm water as it passes through this pervious heart of the paver. This process, that takes mobile containments and passes them through a network of bioremediating plants and roots, renders the containments “nonmobile” and can be removed from the ground to the surface in a stable form. From there, lawn care services can mow biopaved areas and collect the cutting to dispose of containments properly.

"Biopavering" is promoted within the culture of environmentalism through its integration into landscaping. Whether it is on the sidewalks of New York, the parking lots of Wal-marts, or alley ways in between houses, Biopavers play an important role in being a soft, passive response to a large problem. No longer must storm water be treated by a water treatment facility or diluted. Rather, natural processes of plant biology can remediate soil contaminated by past, present, and future industrialization.