Which factors significantly influence the decision to use a porous pavement system?

• A. All of the above
• B. Percolation rates of soils
• C. Rate of rainfall in the design storm
• D. Classification and grading of soils

Answer: (A)

Porous pavement performance hinges on how water moves through the soil, which depends on infiltration capacity, storm characteristics, and soil properties. The soil’s percolation rate determines how quickly infiltrated water can pass downward and away from the surface; if infiltration is too slow, water may pond and the system won’t meet drainage or water-quality goals. The rainfall rate used in the design storm sets the volume and intensity the system must handle; higher-intensity storms require greater infiltration capacity or storage to prevent runoff or surface pooling. The soil’s classification and grading reflect its texture and structure, influencing both infiltration efficiency and vulnerability to clogging or instability under load, which in turn affects maintenance needs and long-term performance. Taken together, these factors shape whether a porous pavement system is appropriate, how it should be sized, and how it will perform, so all of them significantly influence the decision.