Exfiltration Apparatus [ID 06031]



The invention is an exfiltration apparatus that removes pollutants from runoff captured off the roadways. Pollutants may include oils, tire rubber, soil, metallic traces, nutrients, organic chemicals and compounds among others. Such materials lead to the clogging of filtering trenches by the roadside, a situation that worsens during the snow melt and heavy rains. The device construction consists of two main parts: a base and a removable top layer. The top portion contains the first filtering layer which removes the large suspended particles from the run-off and a metallic grate to protect it. The base has bottom and side portions that define the flow of the liquid, and a second filtering layer which filters the finer particles from the liquid. A geotextile material serves as a barrier between the two filtering layers, and between the second filtering layer and the drain. The filtration device is not attached to the road construction and can be easily removed for cleaning, enabling low maintenance. A variety of materials such as porous concrete, sand, porous asphalt, garnet, granular plastic, or activated carbon can be used for filtering.


Commercial Applications

•  Facilitate storm drainage on highways and other roadways

•  Filter run-off from parking lots and other large, hard surface areas susceptible to polluted run– off



•  High flexibility in terms of physical configuration; permitting alterations in device size, fabrication of the base from one or several pieces, provisioning of a sealing element, use of a number of filtering layers and use of a range of materials to meet specific cost or functional requirements

•  Enhances the cost-effectiveness of the highway drainage system by reducing the requirement of drainage trenches being replaced or cracked open due to clogging

•  Reduces damage to the drainage mechanism by providing sufficient strength to withstand heavy traffic conditions.

•  Eliminates requirement of having to dig the roadside for cleaning and replacing of the filtration


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Issued Patents




Patent Information:
For Information, Contact:
Mark Foley
Technology and Commercialization Manager
Ohio University
Gayle Mitchell
Shad Sargand