Rain Gardens as Flood Control in Austin, Texas
description
Transcript of Rain Gardens as Flood Control in Austin, Texas
Rain Gardens as Flood Control in Austin, Texas
By Kiersten Dube
Shoal Creek Detention PondQ: Can rain gardens replace pond?
MOP
AC
Far West Blvd
Shoal
Creek
Lidar to DEM
High
Low ArcGIS Help page “Lidar to raster”
Stream Lines andFlow Accumulation
MOP
AC
Far West Blvd
AGREE50 ft
15 ft
Delineate Watershed
Far West Blvd
Area = 107 acres
Single Family Homes
Revised QuestionCan rain gardens provide flood
control for commercial property?
Civic
Multi-family
Office
Road
s
Assumption
Pond
=
Rain Gardens
Σtime
cfs
Pond Vol = Σ (Rain Garden Vol)
Pond Volume:Cut and Fill Tool
DEM
Artificial DEM
Cut Cut
Fill
Fill = Pond Vol = 2.06 x 106 cubic feet
Weir
Pond
Rain Garden Design
Soil Porosity = 0.2
4 in.
30 in.
10 in.
1.25 in.
EquivalentStorageDepth
Feasibility Assessment
=Pond VolEquivalent RG Depth
Rain Garden Area
=RG AreaWatershed Area 53%
=Pervious CoverPer Lot 56%
?
= 57
57107 =
Acres
Conclusions• Can rain gardens replace pond? – Tentative No
• Consider other options– Pervious paving– Roof top gardens– More complex RG designs
• Remaining questions– Maintenance– Water quality from roads