Green Streets

Green street designs support water management, flood control, landscaping & mobility options.

Benefits & Problems Addressed

Control stormwater, pollution & localized flooding: Street design, materials and landscaping are sized and designed to retain, infiltrate and treat stormwater that traditionally gets routed directly to receiving waterbodies untreated via curbs, gutters and pipes. Green streets also cool stormwater before it drains into waterways, lessinging impacts of heated water on wildlife.

Visual appeal: Landscaping, trees  & paving materials like pavers provide attractive infrastructure and help abate noise. 

Traffic calming:  Overly wides streets are retrofit candidates for greening streets

Tips & Techniques

Planning & preparation: Green streets are appropriate for new and retrofitted streets, roads and alleys.  Soil preparation & long-term maintenance are critical for performance. Engage adjacent homeowners early & target areas with flooding and/or speeding first. Check long term trends to properly size beds and overflow facilities. 

Landscaping: Use plant and landscaping materials that both withstand standing water and require minimal care.  Use non-plant landscaping materials (pebbles, sculpture) to lessen maintenance.  

Paving Materials: New paving includes pervious asphalt and pavers. The subsurface design for infiltrative materials is as important as the surface. 

Street Design for Stormwater Management: Design elements include: recessed beds, trenches, storage chambers

Signage: Use signage to denote responsible agancies, sponsors and donors. Also use for educatino to explain how the green improvements work and provide multiple benefits. 

Hot Buttons:  Comparative costs, Safety concerns (with recessed trenches), trash & weed removal, loss of parking or travel lanes. homeowner cost & responsibility. 

Examples & Resources

Philadlephia Watersheds, Philadelphia PA US

Image credit: American Rivers