3/26/2011
1
DavidDodsURSCorp.,OverlandPark,KS
Photos: David Dods
Year 5
3/26/2011
2
Lessons: With some care and help from us, Mother Nature has an amazing ability to restore degraded lands and waters.
It All Begins with Regional Planning and Site DesignIt All Begins with Regional Planning and Site Design
RainGardensRainGardens Shallow gardens with plants that tolerate periodic saturation
Dry out in a day or two
Restore hydrologic function to the landscape
Habitat
Photo: Barr Engineering; Illustration: Dan Shaw
Attractive Landscaping
Planting Beds Planting Beds --Two ApproachesTwo Approaches
Native Soil
Rain Garden
Engineered Soil + UnderdrainBioretention
Illustrations: Dan Shaw, Waterdrop Innovations; Barr Engineering
3/26/2011
3
Rain Garden Examples:Rain Garden Examples:Common ApplicationsCommon Applications
Photos: David Dods, URS Corp.
Downspout Driveway
Park & Landscape FeaturesPark & Landscape Features((Filtering runoff to protect park lake)Filtering runoff to protect park lake)
Photo: Rusty Schmidt, Waterdrop InnovationsDesign by BNIM Architects
3/26/2011
4
Parking Lot EdgeParking Lot Edge
Photo: David Dods, URS
Parking Lot IslandParking Lot Island
Photo: David Dods
Driveway RunoffDriveway Runoff
Photo: David Dods
Street EdgesStreet Edges
Photo: Rusty Schmidt, Waterdrop Innovations
3/26/2011
5
Design & Photo by BNIM Architects
Water Soil
RainGardenDesignRainGardenDesign1.1. Define Project GoalsDefine Project Goals2.2. Site AnalysisSite Analysis3.3. SizingSizing4.4. Garden Bed Garden Bed
PreparationPreparationl ll l
Plants
5.5. Inlets & OutletsInlets & Outlets6.6. Mulch, Edging, & Mulch, Edging, &
Finishing TouchesFinishing Touches7.7. Care & MaintenanceCare & Maintenance8.8. PlantsPlants
Define Project GoalsDefine Project Goals
What is the purpose of the rain garden?What is the purpose of the rain garden?
yy Remove specific pollutantsRemove specific pollutantsyy Provide detention & volume controlProvide detention & volume controlyy G d t hG d t hyy Groundwater rechargeGroundwater recharge
Design depends upon the goalsDesign depends upon the goals
3/26/2011
6
LocationsLocations Catch Runoff Near the Catch Runoff Near the
SourceSource
Avoid End of Pipe or Avoid End of Pipe or Bottom of the HillBottom of the Hill
Evenly Spread Across theEvenly Spread Across the
Photos: Barr Engineering (L), Portland Stormwater Manual (R)
Evenly Spread Across the Evenly Spread Across the SiteSite
Small Drainage Areas ~ 1 Small Drainage Areas ~ 1 acre or lessacre or less
Catch Water Before it Picks Up Lots of Speed
Where does the water come from?
Where does it flow?
Above-Ground Obstructions: Trees, Power Lines, Structures, Walking Paths, etc.
Below-Grade Utilities: Call in a Utility Check
Utilities
Uphill of Buildings on Slopes
Photo: David Dods
Behind Structural Retaining Walls if Not Designed for Water
y Soil Types & Compactiony Depth to Groundwater and Bedrock
Photo: Barr Engineering
Note asphalt layers
3/26/2011
7
Percolation TestPercolation Test Time how fast the water goes down
How many inches soak away in 24-36 hrs
Illustration: Marjorie Vigoren, City of Plymouth, MNPhoto: Barr Engineering
Runoff VolumeRunoff Volume =
Precip x Drainage Area x Runoff Coeff.
Parking Lot
Building,w/ Flat Roof
Turf
Land Use & Runoff CoefficientsLand Use & Runoff Coefficients(Small Storm Hydrology Method)(Small Storm Hydrology Method)Runoff Coefficients Vary by Land Use and Storm Event Size
Roof
Rv = 0.87 0.23 0.98
(for 1.4 in. storm event)
D th
Length x Width
DepthVolume
3/26/2011
8
When to Use Engineered Soils (When to Use Engineered Soils (BioretentionBioretention))y If not enough area is available for a rain garden, bioretention
can use less spacey Engineered soils drain faster, so the garden can be deeper
and not as widey Meet specific pollutant filtration goal
Max Depth~ 18 (typ)
Garden ExcavationGarden ExcavationKeep Equipment Out of Keep Equipment Out of
Garden toGarden toAvoid CompactionAvoid Compaction
Photos: 1) Kevin Slates, URS, 2) Barr Engineering
Bed Shape:Bed Shape:FlatFlat--Bottomed BowlBottomed Bowl
Illustrations: Dan Shaw, Waterdrop Innovations
Source: The Blue Thumb Guide to Raingardens, by Schmidt, Shaw, & Dods
Garden Bed PreparationGarden Bed PreparationUsing Native SoilsUsing Native Soils
Dig out basic bed shape
Rip & Break up
Photograph: Carla Dods
compacted soils
Till in 3 4 inches compost
Rake out to final shape
3/26/2011
9
Photo provided by: Rusty Schmidt
ReRe--test Infiltration Before Plantingtest Infiltration Before Planting
Photograph: Carla Dods
PlantingPlanting
Photographs: Carla Dods and David Dods
MulchMulchUse Coarse, Double-
Shredded Hardwood
Pinebark Nuggets & Cedar Chips Float
Photos: David Dods
3/26/2011
10
OnOn--Line vs. OffLine vs. Off--Line DesignsLine Designs
On-Line
Off-Line
Off-Line Reduces Erosion Problems
OffOff--Line DesignLine Design
Garden Full
System Overflow
Photographs courtesy of Barr Engineering
Photo: David Dods, URS
Curb Cut, Grass Filter Strip, & Splash PadCurb Cut, Grass Filter Strip, & Splash Pad
Depress Sod below curb
Photo: Barr Engineering
3/26/2011
11
Curb Cut and Sediment Curb Cut and Sediment ForebayForebay
Photo: Barr Engineering
Temporary Bypass During Plant Temporary Bypass During Plant EstablishmentEstablishment
Sandbags to Divert Flow
Photo: Barr Engineering
Outlets:Outlets: Make sure overflows from large Make sure overflows from large storms have a controlled discharge pointstorms have a controlled discharge point
Photo: Rusty SchmidtManhole with a riser
Finishing TouchesFinishing Touches
BordersandEdging:MaketheGardenLookDeliberate
Photographs: Carla Dods; Rusty Schmidt
3/26/2011
12
Maintenance: Maintenance: Typical Landscaping RequirementsTypical Landscaping Requirementsy Weed: 4-5x 1st yr, 3x 2nd yr, then 2x/yr y Prune & Mulch: Annuallyy Clean sand & debris at inlet: 2x/yr
Photo: Barr Engineering
Results of a Successful Garden: Results of a Successful Garden: Infiltration Improves Each Year (Infiltration Improves Each Year (siltysilty clay soils)clay soils)
Lawn:3 / Day
Photo: David Dods
3 / Day
Raingarden:3 / Hour
Reference: Reference: The Blue Thumb Guide to The Blue Thumb Guide to RaingardensRaingardens
Written for upper Midwest, but principles and many of the plants are Written for upper Midwest, but principles and many of the plants are appropriate for Texas tooappropriate for Texas too
Available from Terrace Horticultural BooksAvailable from Terrace Horticultural Books
www.terracehorticulturalbooks.comwww.terracehorticulturalbooks.com
y Rusty Schmidt, Washington Conservation District, Stillwater, MNy Dan Shaw, Waterdrop Innovationsy Kurt Leuthold and Fred Rozumalski, Barr Engineering,
Mi li MNMinneapolis, MNy Marjorie Vigoren, City of Plymouth, MNy Jim Schuessler, BNIM Architects, Kansas City, MOy Carla Dods
3/26/2011
13
QuestionsQuestions
?
[email protected],913.344.1022