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Pervious Paving Illustration

Modular paver blocks installed over a storage area of uniformly-sized crushed rock

Illustration of pervious paving system showing how water filters through layers.
- Adapted from illustration by Doug Adamson.

Close-up photo of spaces between modular pavers. Crushed rock below is visible. Photo showing how several pavers fit together. Close-up photo showing layering of pavers, fine crushed rock, and filter cloth.

Spaces between modular pavers funnel storm water into an 18-inch layer of crushed rock aggregate base. Here, water is temporarily stored as it infiltrates into the soil and groundwater below. Filter cloth allows water to pass through while keeping smaller-sized crushed rock in the upper layer.

Crushed rock layers provide support for vehicles and a storage area to hold water for a short time as it infiltrates into the soil and groundwater below.

A drainage pipe may be needed to move unusual amounts of water to a storm sewer. This pipe insures that, even in extreme weather, all water leaves the parking surface.

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Last Modified: 07/05/2007