Green Stormwater Infrastructure (GSI) Performance Monitoring

February 5, 2019

Welcome.

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Madison Gibler, PE, ENV SPBurns & McDonnell

Priya Iyengar, Project ManagerSmart Sewer Program

City of Kansas City, Missouri

Topics

• GSI Types• Types of Testing• Timeline• Results and Discussion

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Topics

• GSI Types• Types of Testing• Timeline• Results and Discussion

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Vegetated GSI

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Bioretention Basin

Rain Garden

Infiltration Swale

Dry Detention Basin

Wet Detention Basin

Permeable Pavement

Porous Asphalt

Pervious Concrete

Permeable Pavers

Grasscrete

Permeable Articulating Concrete Blocks (PACB)

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Topics

• GSI Types• Types of Testing• Timeline• Results and Discussion

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Vegetated GSI

Types of Testing

Permeable Pavement

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Soil Moisture Testing

Infiltration Testing

Inundation Testing

Water Level Monitoring

Infiltration Testing

Topics

• GSI Types• Types of Monitoring• Timeline• Results and Discussion

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Timeline

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2016 2017 2018

16 Sites 24 Sites 33 Sites

• Infiltration Testing(Double-Ring Infiltrometer)

• Infiltration Testing(Double-Ring Infiltrometer)

• Infiltration Testing• Soil Moisture Testing• Inundation Testing• Water Level Monitoring

Topics

• GSI Types• Types of Monitoring• Timeline• Results and Discussion

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Infiltration Testing

Permeable Pavement

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Permeable PaversASTM C1781

Pervious Concrete& Porous Asphalt

ASTM C1701

Permeable Pavement Infiltration Testing

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Parking Lot

Permeable Pavement Types

B.1 B.3

B.4 B.5B.6

B.2

Pervious Concrete Porous Asphalt Permeable Pavers (Type 1)

GrasscretePermeable Pavers (Type 3)Permeable Pavers (Type 2)

Parking Lot Results

PermeablePavers

Pervious Concrete

Gra

sscr

etePorous

Asphalt

Permeable Articulating Concrete Blocks

Residential Application Urban Application

Open-Jointed Pavers

Permeable Articulating Concrete Block Results

Permeable Pavement Results Summary

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Parking Lot PACB

Pe

rvio

us

Co

ncr

ete

Po

rou

s A

sph

alt

Pe

rme

able

P

ave

rs

Gra

sscr

ete

Pilot Project

Permeable Pavers Pervious Concrete

Pilot Project Results

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0

5

10

15

20

25

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A.1a A.1b A.2a A.2b A.3a A.3b A.4a A.4b A.5a A.5b A.6a A.6b A.7a A.7b

Infi

ltra

tio

n R

ate

(in

/hr)

Testing Site

2017 Infiltration Rate 2018 Infiltration Rate

Pervious Concrete Permeable Pavers

Permeable Pavement Results Summary

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PACBPilot Project Parking LotP

erv

iou

s C

on

cret

e

Po

rou

s A

sph

alt

Pe

rme

able

P

ave

rs

Gra

sscr

ete

Pe

rvio

us

Co

ncr

ete

Pe

rme

able

P

ave

rs

Lessons Learned

Destabilized slope & erosion

Sediment loading from adjacent parking lot

Weed growth in paver joints

Vegetated GSI

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Infiltration Testing

Vegetated GSI

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Infiltration Testing

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Double-Ring Infiltrometer Falling-Head Infiltrometer

Infiltrometer Comparison

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Infiltrometer Results

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Expected Infiltration Ratesbased on Double-Ring Infiltrometer Method

Spring 2017Fall 2017

Fall 2017

Fall 2016

Spring 2017

Fall 2016

Inundation Testing

Vegetated GSI

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Inundation Testing

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Direct flow into rain garden

Measure water level

Inundation Testing Results

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Double-Ring Infiltrometer Infiltration Rates (in/hr)

2016 2017

24.0 9.0

Water Level Monitoring

Vegetated GSI

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Wet Detention Basin

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Pressure Transducer

Wet Detention Basin

Soil Moisture Testing

Vegetated GSI

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Soil Moisture Testing

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Probe

Display

Device

Hand-held device for quick soil moisture readings

Pilot Project Results

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Typical SoilsSaturated 46%

Rain Garden Rain Garden Rain Garden Rain Gardenw/Drain Pipe

Rain Garden Rain Garden Bioretention w/Smart Drain

CascadeRain Garden

Swope Campus Results

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Typical SoilsSaturated 46%

Rain Garden Rain Garden Rain Garden Rain Garden Rain Garden

Infiltration Swale Results

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Typical SoilsSaturated 46%

Infiltration Swale

Soil Composition

Vegetated GSI

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Soil Composition

• Particle Size Analysis – ASTM D422

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Sieve Analysis(No. 100 & No. 200)

Hydrometer

Results (Sieve Analysis)

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GSI Type Raw Sample (grams) % No. 200 passing (Silt and Clay)

Built In

Raingarden w/Forebay 840 8% 2012

Raingarden w/Forebay 1,650 2% 2012

Raingarden w/Forebay 820 6% 2012

Raingarden 160 31% 2006

Raingarden 160 35% 2015

Raingarden 130 41% 2015

Bioretention w/Forebay 330 16% 2017

Bioretention w/Forebay 1,150 9% 2017

Infiltration Swale 200 25%

Soil Texture

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Good for initial Infiltration?

Good for vegetation survival rate?

Lessons Learned

• Double-Ring method is labor intensive.• Falling-head provides a quick and dirty

test. • Site-specific tests/spot checks may not be

representative of an entire GSI. • Adaptive monitoring is key to quantifying

performance of different GSI. • Use monitoring results for better future

design of GSI.

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Questions?

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