Back in 2004, Chicago's Department Of Transportation had no concept of how to build roads and alleys using pervious materials.
Janet L. Attarian writes, "To overcome this obstacle, the department led an aggressive design and investigative process that involved collecting best practices and sample specifications from around the country. CDOT developed its own specifications through a collaborative process involving CDOT staff, the design team, and a materials testing consultant. Together, they established a series of goals, tested the ideas in a laboratory, and then reviewed the results until the final mix designs, materials, and methods were solidified."
The DOT embarked on a number of pilot projects to test out their new-found knowledge, detailed in the full article.
Thanks to Triskele Jim