Pervious Pavement
ELM-PVP-22 Situational / Discouraged Element
Pervious Pavement
A load-bearing paving surface (permeable concrete, porous asphalt, or permeable interlocking pavers) engineered to allow stormwater to infiltrate directly through the pavement surface into a stone reservoir base below, rather than running off.
Why this pattern exists
Applied across a full-width surface (a parking lot, a full travel lane, a plaza), pervious pavement addresses runoff at a larger scale than a pervious strip while still functioning as a normal load-bearing driving or walking surface. This pattern exists to document its own structural and maintenance requirements, which differ meaningfully from conventional pavement.1
Key considerations
- Requires periodic vacuum-sweeping or similar maintenance to prevent surface clogging from sediment, without which infiltration capacity degrades over time
- Structural design (reservoir base depth, subgrade condition) must be engineered for the expected load, not treated as a simple material swap over standard pavement
- Not appropriate in all climates or soil conditions; freeze-thaw cycles and poor native drainage both affect performance and should be evaluated before specifying2
Related patterns
Pervious Strip (ELM-PVS-21) (a related, lower-scale treatment); Surface Parking Lot (FAC-SPL-04) (Facility pattern where this often applies)
References
- Legal / regulatory U.S. Environmental Protection Agency, National Menu of Best Management Practices, "Permeable Pavements" fact sheet.
- Precedent-based National Association of City Transportation Officials, Urban Street Stormwater Guide, "Pervious Pavement."
"Legal / regulatory" here refers to the EPA guidance that municipal NPDES stormwater permits are legally built around, not a single mandatory design spec like MUTCD or PROWAG.