139th Street East cul-de-sac

Location: Tacoma

Owner/developer: Pierce County Public Works and Utilities

Project team: Northwest Cascade, general contractor; Pierce County Public Works and Utilities, architect and structural engineer; Tyee Concrete Construction, concrete contractor; Corliss Resources, ready-mix supplier

Flooding on 139th Street East in the Tacoma area would keep people out of their homes for weeks at time during high groundwater events.

A Pierce County pilot project sought to use pervious concrete to address the groundwater flooding. The project was the first time the county had used pervious concrete for a public road.

Work involved raising the road grade two feet and replacing the conventional pavement.

Most of the time, pervious concrete allows water to infiltrate through the pavement and into the soil. But during groundwater events, pervious concrete works in reverse: It allows the groundwater to rise through the pavement while still providing a drivable surface for residents and emergency vehicles.