Pervious concrete

Pervious concrete is a rigid pavement that uses a cementitious material to bind aggregates. Fine materials are reduced or eliminated to allow gaps in the surface, which allow water infiltration to the aggregate base layer. As with other permeable systems, ongoing maintenance is crucial to avoid plugging the voids. This medium typically is used in pedestrian and bicycle pavements, such as low volume sidewalks or trails, but the rougher surface may be less desirable for wheeled vehicles such as walkers, strollers or scooters. The surface can become slippery when low use allows moss to grow in the voids. The material is more desirable for vehicles with a speed of 35 miles per hour or less, and is used in parking lot drive lanes and neighborhood streets.

FEATURED SITE - Firstenburg Community Center and Cascade Community Library

700 NE 136th Ave., Vancouver

This LEED Gold-certified facility was built in 2006 to accommodate a new community center, complete with fitness center, recreational pool, exercise rooms, indoor track, gymnasium, climbing wall, senior center, classrooms, teen center and community rooms with kitchen service. The adjacent Cascade Community Library was built in 2009.

Pervious concrete – Approximately 140,000 square feet of pervious concrete covers 341 parking spaces to serve both buildings.

Site planning and design – The center was designed to preserve many existing Douglas firs that shade the site and add an aesthetic element; diseased trees were removed, milled, and used in the building’s construction.

Native plantings – Landscape beds in parking lot islands and around buildings use native plantings, reducing the need for irrigation; plantings have a naturalized look to complement the mature trees.