Download - Rain gardens presentation julia jones
RAIN GARDENSJulia Jones
Purpose
“Rain gardens can effectively trap and retain 99 percent of common pollutants in urban storm runoff, potentially improving water quality and promoting the conversion of some pollutants into less harmful compounds”
The Problem• Typical urban setting 75%
impervious coverage• 50% storm water runoff• Pollution
• Metals• Oils• Fertilizers• Other “particulate matter”
The Solution• Rain garden hydrologic
cycle• Two types
• Under-drained• Infiltration not desire• Pipes transport clean water• Porous planting media• 2 hours to drain
• Self-contained• Infiltration • Porous planting media• 4 hours to drain
RAIN GARDENS IN SITE PLANNING
Site Inventory• Issues
• Erosion• Compaction of soil• Excess runoff volume• Eye sores
• Positive Attributes• Good views• Existing vegetation and plant
species• Travel patterns
Site Inventory• Features
• Wind and sun direction• Noise pollution• Infrastructure• Site drainage patterns• Slopes• Soil types
Site Analysis
Placement and Size • Moisture and
water issues• Traffic patterns• Wildlife• The cost of
excavation
Site Analysis
Type• Moisture• Soil types• Environmental
and aesthetic functions
• Maintenance initiatives
Case Study• 2 year study conducted
• Michael Dietz and John Clausen of the University of Connecticut
• Storm water runoff from rooftops
• Significantly reduced concentrations of nitrates, ammonias, phosphorus, and other pollutants
Lansing Michigan• Sewage overflow plan• Incorporated in the streetscape• Michigan Ave
CONCLUSION• Rain gardens are effective• Practical and aesthetically pleasing• Incorporated in site planning process