This document discusses how green infrastructure reduces wet weather issues by managing stormwater through natural systems like soil and vegetation rather than traditional pipe and concrete infrastructure. It provides examples of green infrastructure technologies like porous pavement, bioretention cells, tree trenches, planter boxes, cisterns, vegetated roofs, and green streets that intercept and reduce stormwater flows to combined sewers. These approaches provide storage, infiltration and treatment of stormwater runoff to reduce flooding, erosion, CSO events and costs compared to gray infrastructure.

1. What is Green Infrastructure and How
Does It Reduce Wet Weather Issues?
Making natural systems work for us:
using soil and vegetation - rather than concrete and pipe,
to manage stormwater volume, rate, and water quality impacts
Prepared for:
Onondaga County, New York
Prepared by:
October 2008
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2. During dry weather, sanitary flows are
collected in combined sewers for
treatment at Metro
Catch Basin
Combined
Sewer
Sanitary
Sewer
Dry Weather
Flow Creek
Interceptor Sewer to
Wastewater
Treatment Facility
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3. During wet weather, inflows exceed
the collection system’s capacity and
trigger a CSO
Roof
Leaders
Stormwater
Runoff Catch Basin
Combined Combined
Sewer Sewer
Sanitary
Sewer Overflow
Creek
Interceptor Sewer to
Wastewater
Treatment Facility
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4. Green solutions intercept and reduce
stormwater flows to sewers, providing
storage, infiltration, and treatment
Roof
Leader
Vegetated
Stormwater Swale
Runoff
Porous
Roadway
Sanitary
Combined Sewer Sewer
Dry Weather
Flow Creek
Interceptor Sewer to
Wastewater
Treatment Facility
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5. Green infrastructure reduces….
 Flooding
 Erosion
 Stormwater runoff volume
 Stormwater pollutant loadings
 CSOs
 Gray infrastructure operation, maintenance, energy
and treatment costs
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6. Green Infrastructure Technologies
and Example Applications
 Porous pavement  Bioretention/vegetated infiltration
 Parking lots  Rain Gardens
 Roadways  Vegetated curb extensions
 Sidewalks  Tree trenches
 Basketball courts  Planter boxes
 Cisterns for capture/re-use
 Vegetated roofs
 Green streets
 Combinations of the above
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7. Porous Pavement Parking Lot
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8. Porous Pavement
Paver Roadway
Porous Pavement Asphalt Roadway
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9. Porous
Pavement
basketball court
sidewalk
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10. Rain Garden (bioretention/vegetative infiltration)
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11. Vegetated Curb Extension –
Plan View
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12. Vegetated Curb Extension –
Profile View 12

13. Tree Trench
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14. Tree Trenches along Street
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15. Planter Box
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16. Cistern for Capture/Re-use
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17. Vegetated Roof
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18. Vegetated Roof
under construction
finished roof
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19. Green Streets…putting it all
together
Portland State University Street Planters
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20. Image Source: A Civic Vision for the Central Delaware
Green Streets…putting it all together ~ “Catch the Rain”
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21. Green Infrastructure improves:
 Water quality
 Air quality
 Neighborhood aesthetics
 Habitat and biodiversity
 Recreational and transportation opportunities
 Property values
 Community health and vitality
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