approaches for selecting bmps and estimating their performance · approaches for selecting bmps and...

1

Approaches for Selecting BMPs and EstimatingTheir Performance

Stephen Carter, PE

The Moving Target

Starting point

Reference condition

Naturally evolvedstream condition

2

The Moving Target

Change Due toAgricultural Use

Hydrologic impacts

New pollutant sources

The Moving Target

Development

Increasedimperviousness

Increased runoff

Additional pollutantsources

3

Typical Trend

De

gra

da

tion

Ma

na

ge

me

ntA

ctio

ns

WaterQuality

Degradation

ManagementActions

BMPs

ChangingBehaviors

SmartGrowth

What’s the Goal?

De

gra

da

tion

Target

Water quality criteria

Reference watershedcondition

TMDL

Ma

na

ge

me

ntA

ctio

ns

Existing Condition

Water quality

Pollutant load

4

De

gra

da

tion M

an

ag

em

en

tActio

ns Components of the

Watershed Plan

Specificmanagement actions

Pollutant loadreduction

Improved waterquality

What’s the Goal?

< 1 – 10 Acres: LID (Rain Barrels, Bioretention)

10 – 100 Acres: Grassed Swales,Ponds

> 100 Acres: RegionalFacilities,

Stream Restoration

TMDL

10,000s or100,000sActivities

Result inLoadReduction

Bo

ttom

–U

p

To

p–

Do

wn

Structural BMPs

5

ASCE BMP Database

9

ASCE BMP Database

10

6

ASCE BMP Database

11

BMP Processes

Background InfiltrationMedia FiltrationSettlingOrifice OutflowBypass Flow

Small Medium

UntreatedBypass

Attenuated OrificeOutflow

Media Filtration(Underdrain Outflow)

Large

100%

(% Treated)

50%

(% Treated)

10%

(% Treated)

7

BMP Decision Support System (BMPDSS)

Prince George’s County, MDNational leader in stormwater and watershedmanagement – one of the most innovative andhighly reference programs in the country

Highlights: Basis for national strategies to address

stormwater challenges First and most referenced LID

guidance and design manuals Developed the BMP Decision

Support System (BMPDSS)

BMPDSS Interface

BMPDSS Set Up

BMPDSS Output:BMP Optimization

BMP Decision Support System (BMPDSS)

14

8

BMP Class A: Storage/Detention

OverflowSpillway

BottomOrifice

Evapotranspiration

Infiltration

Outflow:Inflow:

Modified Flow &Water Quality

From Land Surface

Storage

UnderdrainOutflow

Process-Based. Continuous Simulation.

BMP Class B: Open Channel

Outflow:Inflow:

From Land Surface

Overflow atMax Design

Depth

Open Channel Flow

Evapotranspiration

InfiltrationUnderdrain Outflow

Modified Flow &Water Quality

Process-Based. Continuous Simulation.

9

BMP Performance Curve Concept

Performed for EPA Region 10

BMPs curves developed fromcalibrated models and detailedperformance data

Provides long-term cumulativeperformance estimates basedon BMP capacity

Eliminates the need for detailedmodeling and evaluation inindividual applications 0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

0.25 0.75 1.25 1.75 2.25

BMP size (controlled depth of runoff)

Pe

rce

nta

ge

rem

ov

al

for

TS

S

40%

0.65 in

0.90 in

BMP I

BMP II

Land simulation(SWMM)

Surface runoff generationand pollutant wash off

BMP simulation(BMPDSS)BMP Treatment

Precipitation

BMP Performance Curve Development Scheme

BMP Performance Curve: Gravel Wetland

Land Use: Commercial

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

Depth of Runoff Treated (inches)

Po

llu

tan

tR

em

ov

al

TSS TP Zn

10

BMPDSS Calibration for Event 1/12/2006:Hydrology

0

50

100

150

200

2501

9:0

0

19

:40

20

:20

21

:00

21

:40

22

:20

23

:00

23

:40

0:2

0

1:0

0

1:4

0

2:2

0

3:0

0

3:4

0

4:2

0

5:0

0

5:4

0

6:2

0

7:0

0

7:4

0

8:2

0

9:0

0

9:4

0

10

:20

11

:00

Time

Flo

w(g

pm

)

Observed inflow

Generated inflow to infiltration system

Observed outflow

Calibrated BMPDSS outflow

BMPDSS Calibration: Water Quality

PollutantsCalibration events TSS TP Zn

Inflow 72.13 0.16 0.11ObservedEMC (mg/L) Outflow 0.17 0.03 0

Calibratedoutflow

0.17 0.03 0.006

Decay 0.76 0.31 0.4708/13/2005

BMPDSSperformance

Perct.removal

0.93 0.70 0.85

Inflow 52.06 0.10 0.03ObservedEMC (mg/L) Outflow 0 0.01 0

Calibratedoutflow

0.03 0.01 0.001

Decay 0.73 0.29 0.4401/12/2006

BMPDSSperformance

Perct.removal

0.90 0.65 0.81

Inflow 94.03 0.12 0.04ObservedEMC (mg/L) Outflow 0 0.02 0

Calibratedoutflow

0.01 0.02 0

Decay 0.73 0.21 0.4405/09/2006

BMPDSSperformance

Perct.removal

0.91 0.50 0.79

Decay 0.74 0.27 0.45Calibrated parameters Perct.

removal0.91 0.62 0.82

11

BMP Representation in BMPDSS

Generation of BMP Performance Curves

Commercial

Industrial

High-densityresidential

Medium-densityresidential

Low-densityresidential

Land uses(5)

Infiltration basin(6 infiltration rates)

Infiltration trenches(6 infiltration rates)

Bio-retention

Porous pavement

WQ Swales

Extended dry detention

Wet pond

Gravel wetland

BMPs(8) Pollutants

TSS

TP

Zn

Pollutants(3)

90 Figures and 282 Curves in total

12

Infiltration Trench

BMP Performance Curve: Infiltration Trench

Land Use: Industrial

(Soil Infiltration Rate 0.52 in/hr)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

Depth of Runoff Treated (inches)

Polluta

ntR

em

oval

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Runoff

Volu

me

Reduction

TSS TP Zn Volume

Infiltration Trench

13

Wet Pond

Wet PondB M P P e rfo rm an c e C u rve : W et P o nd

L an d U se : C o m m e rcial

0%

1 0%

2 0%

3 0%

4 0%

5 0%

6 0%

7 0%

8 0%

9 0%

1 0 0%

0 0.2 0 .4 0 .6 0.8 1 1.2 1 .4 1 .6 1.8 2

D e pt h of R u no ff T re at e d ( in ch e s )

Po

llu

tan

tR

em

ov

al

TS S TP Zn

14

Curve Extrapolation Tool

BMP Scale Considerations

SiteRegional

15

Lake Tahoe

Decline of Lake Tahoe Clarity

UC DavisTahoe Environmental Research Center

16

Pollutant Load Budget

Urban

Forested

AtmosphericDeposition

StreamChannelErosion

Groundwater

ShorelineErosion

15%

16%

54%

13%

Total Nitrogen

Pollutant Load Budget:

TotalPhosphorus

Urban

Forested



Groundwater

ShorelineErosion

38%

26%

15%

15%

17

Pollutant Load Budget

Fine SedimentParticles

Urban

Forested



ShorelineErosion

71%

9%

16%

4%

Lake Tahoe Source Category Groups(SCGs)

3. Stream Bank ErosionLake Tahoe

1. Atmospheric Deposition

4. Urban & Groundwater

2. Forest Upland

18

Atmospheric Deposition

Settings Four spatially based settings, measured by concentric rings of distance from the lake

TiersFour tiers per setting were applied, based on two different treatment levels from two differentgroups of pollutant sources. The first group was vehicle emisions, and the second groupincluded transportation infrastructure or structural controls

Forest Uplands

SettingsThree source based settings, including (A) unpaved roads, (B) highly erodible forest andrecreational areas, (C) burned, plus harvested, plus relatively undisturbed forest areas

Tiers Three tiers per setting with increasing degree of treatment: low, medium, and high

Stream Channel

SettingsThree treatable segments along the top three most sediment-productive streams in the Basin:(1) Blackwood Ck, (2) Upper Truckee, and (3) Ward Creek

Tiers Three levels of treatment with varying intensities and stabilization activities

Urban Upland

SettingsFour settings based on the different combinations of slope (moderate or steep) and imperviousconfiguration (concentrated or dispersed).

TiersTwo tiers of differing intensity and sophistication of treatment activities, plus a third "Pump andTreat" stormwater tier for concentrated impervious areas only

Management Settings and Tiers

0%

10%

20%

30%

40%

50%

60%

70%

80%

$0 $1 $2 $3 $4 $5 $6 $7 $8 $9 $10 $11 $12 $13 $14

Cost ($ Billion)

Lo

ad

Red

ucti

on

(%)

Fines (Tonnes) Fines (Particles)

Total Nitrogen Total Phosphorus

Theoretical Maximums per Billion Dollars Invested

19

Agua Hedionda Watershed Management Plan

Unincorp.Area

Unincorp.Area

78

Carlsbad

Oceanside

Vista

San Marcos

I-5

SR-76 EB

I-5

78

EL CAM REAL

SUNSET DR

TAMARACK AV

CA

RLS

BA

DB

L PO

INSETT

IAAV

SY

CA

MO

RE

AV

MARVIS

TADR

BUENACREEK

RD

LAKE BL

SSAN

TAFE

AV

0 1 20.5Kilometers

0 0.9 1.80.45Miles

Agua Hedionda - Modeling SubwateshedsNAD_1983_StatePlane_California_VI_FIPS_0406_Feet

Map produced 03-24-2008 - Peter Cada

Legend

Subwatersheds

Streams

Water

Roads

20

Model - LSPC

Hydrologic Components:

Precipitation

Interception

Evapotranspiration

Overland flow

Infiltration

Interflow

Subsurface storage

Groundwater flow

Groundwater loss

Schematic of Stanford Watershed Model

Stream Segment

StormwaterTreatment

2EffluentConc.

UntreatedBypass

StormwaterTreatment

1EffluentConc.

UntreatedBypass

Overflow

Infiltration goes to nearby urban pervious baseflow

Drainage Area boxesrepresent a mix of land

use.

Untreated

HydrologicSourceControl

Impervious

ToSWT1ToHSC1 ToSWT2 ToStream

55%5%40%

55% 30%10% 5%

BMP Scenario

21

Storm Hydrograph

0

500

1,000

1,500

2,000

2,500

3,000

0 6 12 18 0 6 12 18 0 6 12 18

Hour

Flo

w(c

fs)

Existing Scenario

Predevelopment Scenario

Future Scenario w/o BMPs

Future Scenario w/ BMPs

2/12/2001 - 2/14/2001

Sediment Loading at Lagoon

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

Existing

Scena

rio

Prede

velopm

ent S

cena

rio

Futu

reSce

nario

w/oBM

Ps

Futu

reSce

nario

w/ BM

Ps

Se

dim

en

tL

oa

d(T

on

s/Y

r)

22

City of San Diego Evaluation of Structural andNonstructural BMP Performance

Chollas CreekWatershed

LSPC Model

Suspendedsediment

Trace metals• Copper

• Lead

• Zinc

Bacteria

43

Chollas Creek WatershedReaches Used in Model

0 1 2 30.5

Km

0 0.6 1.20.3Mi

NAD_1983_StatePlane_California_VI_FIPS_0406_FeetMap Produced 10/27/2009 by E. Moreno

Legend

Streams

Chollas Watershed

Modeling Scenarios

Long-term simulations (e.g., 10 years)

Capture a range of conditions

Scenarios

Current conditions• Baseline scenario for comparison

Management scenarios• Individual BMPs

• Combinations

44

23

Modeled BMPs

Modeled BMP Scenarios and Combinations

Irrigation control ● ● ● ●Hydrologic source control

Bioretention ● ● ● ●Stormwater control

Detention basin ● ● ●Source control

Copper reduction ● ● ●Bacteria reduction ● ● ● ●Street sweeping ● ● ● ●

45

BMP Representation within a Watershed Model

LSPC does not include explicit representation of individualBMPs

Assumptions are developed to represent BMPs

Modeling assumptions can be based on

Specified BMP operational or design requirements

BMP literature information

Special studies on BMP performance

46

24

Source Control

Reach Outflow

Storm Drain Reach

Time

Ru

no

ff

Lower PollutantLevels

Time

Ru

no

ff

Pollutant Buildup

Land UseParcel

Time

Po

lluta

nt

Le

vel

47

Source Control

Examples

Reduced irrigation, treet sweeping, brake padmodification, pet BMPs

48

25

Modeled BMPs






49

Irrigation Control – Model Application

Targeted land uses Parks

Residential areas

Industrial

Commercial

Schools

Reduce

10, 20, 40, 75%

50

Land UseAgricultureCommercialHealthCareSchoolPublicCemeteryGolfLandscapeOpenOpenRecParkMobileHomeParksMultiFamilyResidentialSingleFamilyResidentialSpacedRuralResidentialFreewayRoadMilitaryParkingIndustrialTrainTransportationWarehousingPublicStorageWater

0 1 20.5

Kilometers

0 1 20.5

Miles

Targeted Irrigation Control Land UsesNAD_1927_StatePlane_California_VI_FIPS_0405_feet

Map produced 03-18-2010

26

Irrigation Control – Monthly Reductions

51

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

Oct

ob

er

No

vem

be

r

De

cem

be

r

Jan

uar

y

Feb

ruar

y

Mar

ch

Ap

ril

May

Jun

e

July

Au

gust

Sep

tem

be

r

Vo

lum

e

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

Oct

ob

er

No

vem

be

r

De

cem

be

r

Jan

uar

y

Feb

ruar

y

Mar

ch

Ap

ril

May

Jun

e

July

Au

gust

Sep

tem

be

r

Co

pp

er

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

Oct

ob

er

No

vem

be

r

De

cem

be

r

Jan

uar

y

Feb

ruar

y

Mar

ch

Ap

ril

May

Jun

e

July

Au

gust

Sep

tem

be

r

Feca

lCo

lifo

rm

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

Oct

ob

er

No

vem

be

r

De

cem

be

r

Jan

uar

y

Feb

ruar

y

Mar

ch

Ap

ril

May

Jun

e

July

Au

gust

Sep

tem

be

r

Sed

ime

nt

Modeled BMPs






52

27

Source Control – Cu Red. Targeted Land Use

Targeted land uses

Roads

Freeways

All Impervious*

53

0 1 20.5

Kilometers

0 1 20.5

Miles

Roads Targeted for Copper ReductionsNAD_1927_StatePlane_California_VI_FIPS_0405_feet


Freeway

Road

Source Control – Cu Red. Mobile Sources

Reduction in copper onroads by targetedreduction

Brake dust isresuspended depositson other land uses

Assumed a reduction of½ of road reduction

54

Roads

OtherAreas

28

Source Control – Cu Red. Load Reductions

55

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Co

pp

er

Water Year

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

Oct

ob

er

No

vem

be

r

De

cem

be

r

Jan

uar

y

Feb

ruar

y

Mar

ch

Ap

ril

May

Jun

e

July

Au

gust

Sep

tem

be

r

Co

pp

er

Modeled BMPs






56

29

Source Control – Bacteria Targeted Land Use

Targeted landuses

Residential

Parks

57

Land UseAgricultureCommercialHealthCareSchoolPublicCemeteryGolfLandscapeOpenOpenRecParkMobileHomeParksMultiFamilyResidentialSingleFamilyResidentialSpacedRuralResidentialFreewayRoadMilitaryParkingIndustrialTrainTransportationWarehousingPublicStorageWater

0 1 20.5

Kilometers

0 1 20.5

Miles

Targeted Bacteria Control Land UsesNAD_1927_StatePlane_California_VI_FIPS_0405_feet


BMP Model Application

Reduce bacteria levels by 10, 20, 40 and 80%

Reduce POTFW

Reduce SQOLIM and WSQOP

58

Different BMPsimulations

BMP effectiveness

Lo

ad

red

ucti

on

30

Source Control – Bacteria Storm EMC Reductions

59

Storms ≤ 0.6 in Storms > 0.6 in

100

1,000

10,000

100,000

100 1,000 10,000 100,000

BM

PF

ec

alC

oli

form

(mg

/L)

Baseline Fecal Coliform (#/100mL)

100

1,000

10,000

100,000

100 1,000 10,000 100,000

BM

PF

ec

alC

oli

form

(mg

/L)

Baseline Fecal Coliform (#/100mL)

Modeled BMPs






60

31

Street Sweeping – Swept Roads

61

Swept RoadsUnswept roads

0 1 20.5

Kilometers

0 1 20.5

Miles

Swept RoadsNAD_1927_StatePlane_California_VI_FIPS_0405_feet


Street Sweeping Effects

Reduce pollutant levelson roads

62

Str

ee

tS

weep

ing

Str

ee

tS

weep

ing

Rain

Time

Po

lluta

nt

Sto

rage

32

Street Sweeping – Load Reductions

63

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Vo

lum

e

Water Year

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Co

pp

er

Water Year-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Feca

lCo

lifo

rm

Water Year

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Sed

ime

nt

Water Year

Street LoadsBacteria Load -15%Copper Load – 36%

Modeled BMPs






64

33

Combination Simulations – Annual Loads

65

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Vo

lum

e

Water Year

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Co

pp

er

Water Year-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Feca

lCo

lifo

rm

Water Year

-100%

-90%

-80%

-70%

-60%

-50%

-40%

-30%

-20%

-10%

0%

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

20

05

Sed

ime

nt

Water Year

Combination Simulations –Loads by Storm Size

66

0.1

1

10

100

1000

0.01 0.10 1.00 10.00

Co

pp

er

(ug

/L)

Rain (in)

100

1,000

10,000

100,000

0.01 0.10 1.00 10.00

Fe

ca

lCo

lifo

rm(#

/10

0m

L)

Rain (in)

1

10

100

1,000

10,000

0.01 0.10 1.00 10.00

TS

S(m

g/L

)

Rain (in)

0

1

10

100

1,000

10,000

0.01 0.10 1.00 10.00

Pe

ak

Flo

w(c

fs)

Rain (in)

34

BMP Scale Considerations

SiteRegional

What is SUSTAIN?

SUSTAIN – System for Urban Stormwater Treatment,and Analysis INtegratration

An ArcGIS-based framework designed to supportevaluation and decision-making:

How effective are BMPs or green infrastructure (GI) inreducing runoff and pollutant loadings?

What are the most cost-effective BMP options meeting thewater quantity and quality objectives?

• Where, what type, and how large?

35

Where It Applies?

Evaluate and select BMPs to achieve loading targets set by aTMDL

Identify protective management practices and evaluate pollutantloadings for Source Water Protection

Develop cost-effective management options for a municipal MS4program

Determine a cost-effective mix of green infrastructure measures tohelp meet optimal flow reduction goals in a CSO control study

SUSTAIN Components

Interpretation (PostProcessor)

Optimization

36

Implementation andData Collection

0%

5%

10%

15%

20%

25%

30%

35%

$0.0 $0.5 $1.0 $1.5 $2.0 $2.5 $3.0 $3.5 $4.0 $4.5

Cost ($ Million)

Eff

ective

ne

ss

(%R

ed

uctio

n)

All Solutions

Cost-Effectiveness Curve

Selected Simulation

BMP Optimization

Cost Effectiveness (CE) Curve

37

$0.0

$0.5

$1.0

$1.5

$2.0

$2.5

$3.0

$3.5

$4.0

$4.59

.9%

14

.1%

16

.6%

18

.4%

20

.3%

22

.1%

23

.4%

24

.2%

24

.8%

25

.7%

26

.6%

27

.3%

27

.9%

28

.5%

29

.6%

30

.2%

30

.6%

30

.8%

31

.1%

31

.6%

31

.8%

32

.1%

32

.4%

32

.9%

Effectiveness (% Reduction)

Co

stD

istr

ibu

tio

n($

Mill

ion

)

DRYPOND BIORETENTION

RAINBARREL POROUSPAVEMENT

Selected Simulation

55%24%

0%

21%

BMPs Selected

55%24%

0%

21%

BMP Optimization

Milwaukee Municipal Sewerage District

Proposed ultimate goal of eliminating alloverflows by 2035

Explore potential benefits of widespreadadoption of green infrastructure (GI) toreduce overflows

Potential benefits measured by: Environmental outcomes (pollution

reductions)

Economic and social outcomes (triple bottomline)

38

BMP Configuration:Aggregate BMP Network

$0.0

$10.0

$20.0

$30.0

$40.0

$50.0

$60.0

$70.0

$80.0

$90.0

38%

44%

48%

50%

54%

56%

58%

60%

61%

63%

65%

67%

68%

70%

72%

73%

75%

76%

77%

79%

80%

80%

81%

82%

82%

83%

83%

83%

83%

84%

84%

84%

84%

84%

85%

Effectiveness (% Reduction)

Co

st($

Mill

ion)

Rain Barrel Regional Bioretention

Rain Gardens Green Alley

Porous Pavement Block Bioretention

Green Roof

30%

40%

50%

60%

70%

80%

90%

$0.0 $10.0 $20.0 $30.0 $40.0 $50.0 $60.0 $70.0 $80.0

Cost ($ Million)

Eff

ectiv

ene

ss(%

Redu

ctio

n)

All Solutions

Cost-Effectiveness Curve

Selected Solution

Selected Solutions

1%17%

6%

17%

31%

28%

0%

Reduction:

66.0%

Cost:

$10.6 Mil

Cost-EffectiveSolutions

39

Results:BMP Utilization

Solution Cost($ million)

Annual VolumeReduction (%)

1 $7.2 55.4%

2 $10.6 66.0%

3 $15.7 72.6%

4 $32.0 81.9%

0%

20%

40%

60%

80%

100%

Porous

Pavement

Green Alley Block

Bioretention

Rain Garden Regional

Bioretention

Rain Barrel Green Roof RoadSide PP Green Street

- PP

Green Street

- BR

Pe

rce

nt

BM

PU

tili

zati

on

Solution 1 (55%) Solution 2 (66%)

Solution 3 (73%) Solution 4 (82%)

Results: WaterQuality Benefit

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Flow Peak Flow TSS TN TP

Pe

rce

nt

Re

du

ctio

n

Solution 1 Solution 2 Solution 3 Solution 4

Solution Cost($ million)

Annual VolumeReduction (%)

1 $7.2 55.4%

2 $10.6 66.0%

3 $15.7 72.6%

4 $32.0 81.9%

40

Social, economic, and environmental benefits of greeninfrastructure

Need to illustrate benefits to motivate change More beautiful neighborhoods, higher property values, improved safety

and increased jobs

Environmental stewardship benefits

Triple Bottom LineAnalysis

Job Creation

Reduced Infrastructure Cost

Reduced Pumping Costs

Increased Property Values

Improved Quality of Life andAesthetics

Increased RecreationalOpportunities

Reduced Stormwater/Sediment

Increased GroundwaterRecharge

Carbon Sequestration

Reduced Energy Use andHeat Island Effect

Develop a technical framework

for a Water Quality Funding

Initiative

Provide a tool for urban runoff

and stormwater quality

management that allows for:

BMP implementation at

local scale

Watershed management at

regional scale

LA County Department of Public Works

41

81

Linked models

Loading SimulationProgram C++ (LSPC)

EPA’s SUSTAIN

Methods foroptimization of BMPplacement and design

Locally derived costfunctions

Partnership with EPA

Watershed Management Modeling System (WMMS)

82

Overview of WMMS

Total area > 8,000 squarekilometers

Land characteristics

148 precipitation gages

Modeled pollutants andTMDL targets include: TN,TP, TCu, TPb, TZn, andFecal Coliform

Compliance required atapproximately 300 locations

42

Categories

Management Categories and Levels

Management Categories

Based on physiography:

• slope, impervious area, imperviousconfiguration, roads density

Factors that drive BMP selection

Management Levels

Combinations of BMPs

Increasing degree of controlsrepresented

Includes associated costs

Levels

The Watershed

D, $

D, $

D, $

ReductionOpportunity Matrix

Small-Scale Model Configuration

Treatmentpathways fromfour generalizeddrainage areas

DistributedStructural BMPs

PermeablePavement

Bioretention

Rain Barrels

43

Cost versus Load Reduction

Management Levels

Discrete intervalsalong the maximumfeasible treatmentcurve

Levels 20%,40%,60%, 80%, &100%

85

0

50

100

150

200

250

300

20% 40% 60% 80% 100%

Level I Level II Level III Level IV Level V

Management Levels: Percent of Maximum Zinc Removed

Co

st

Eff

ect

ive

ne

ss($

1,0

00

/lb

-rem

ove

d/a

cre

)

Subwatershed C-05

Subwatershed C-50

Subwatershed C-95

Degrees of Practice

Risk-based approach for compliance optimization:

Instream Targets Subwatershed Management Levels

Degree of Practice = Allowable exceedences under extremeconditions

Degree of PracticeWet-Weather AllowableExceedence (Percent of

Time)

Wet-Weather TMDLCompliance

(Percent of Time)

I 25% 75%

II 15% 85%

III 10% 90%

IV 5% 95%

V 0% 100%

86

44

Management Level (V)100% Degree of Protection

100% wet-weathercompliance

Even with uniformapplication ofManagement Level V,most points do notcomply at the 100%Degree of Protection

87

Management Level (V)85% Degree of Protection

Total Treatment Cost:$44.48 billion

No Centralized BMPsRequired

For uniform applicationof Management LevelV, all points comply atthe 85% Degree ofProtection

88

45

Total Treatment Cost:$23.33 billion

Additional CentralizedBMPs for compliance:$1.09 billion

Total: $24.42 Billion

89

Management Level (IV)85% Degree of Protection

Cost Distribution vs. DoP for Proportional Scenario

90

46


91


92

47


93


94

48

Total “Compliance” Cost by Management Level andDegree of Practice ($ Billion)

95

Total ComplianceCost ($ Billion)

96

Storm Size Analyses

• Load reduction by rainfall event

0% 0% 0% 0% 0% 0% 0% 1% 4% 1% 4% 5% 14% 7% 38% 25%0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0.0

4

0.0

8

0.1

6

0.2

4

0.3

2

0.3

6

0.4

4

0.5

6

0.7

2

0.8

0.9

6

1.2

2

4.7

2

5.0

4

6.5

6

7.2

8

Precipitation Event Volume (in)

Co

pp

er

Lo

ad

Red

uc

tio

n

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Re

lati

ve

Co

ntr

ibu

tio

n(B

as

eli

ne

)

Relative Contribution Pre-Developed Reduction (45%) Reduction (55%) Reduction (65%)

49

TMDL Implementation/Water Quality ImprovementPlanning

Multi-Pollutant TMDL ImplementationPlans for Los Angeles CountyAddress multiple TMDLs for BallonaCreek and Los Angeles River

Highlights: Integrated water resources

approach Field investigations of potential

BMP sites Application of WMMS Negotiations with regulators on

interpretation of TMDLs, water qualitystandards, and MEP

Los Angeles River and Ballona Creek Watersheds

NAD_1983_StatePlane_California_V_FIPS_0405_FeetMap produced 05-20-2009 - P. Cada

Hwy 10

Hwy 101

Hwy 60

LADERAHEIGHTS

FLORENCE-FIRESTONE

Tujunga Wash

Pac

oim

aW

ash

Los Angeles River

RioHondo

Ballo

na

Cre

ek

Com

pton

Cr

Seco

Arroy

o

LACRESCENTA

ALTADENA

Silver Lake(No Drain)

EAST RANCHODOMINGUEZ

SOUTH SANGABRIEL

WHITTIER

EAST LA

Hwy 14

Hwy 105

Hwy 91

Hw

y5

Legend

Major Road

Major Water Features

Ballona Creek Watershed

Los Angeles River Watershed

Unincorporated County Area

Federal Land

Angeles National Forest

Santa Monica Mountains NRA0 4 82 Miles

0 4 82 Kilometers

PacificOcean

VenturaCounty

OrangeCounty

Los AngelesCounty


Pollutant sourcecharacterization andprioritization

LA River - Modeled Wet Weather LoadingFecal Coliform (#/ac/yr)

NAD_1983_StatePlane_California_V_FIPS_0405_FeetMap produced 07-22-2009 - B. Tucker

Hwy 10

Hwy 101

Hwy 80

Tujunga Wash

Pa

c o

i ma

Was

h

Com

ptonC

r

Los Angeles River

Arroyo

Seco

RioHon

do

ALTADENA

Hwy 14

Hwy 105

Hwy 91

Hw

y5

OAT MOUNTAIN

EAST LOS ANGELES

FLORENCE - FIRESTONEWHITTIER NARROWS

LA CRESCENTA - MONTROSE

WEST CHATSWORTH

SYLMAR ISLAND

KINNELOA MESA

RANCHO DOMINGUEZ

SANTA CLARITA VALLEY

KAGEL CANYON

WALNUT PARK

W ATHENS - WESTMONT

LOPEZ CANYON

SOUTH SAN GABRIEL

W RANCHO DOMINGUEZ - VICTORIA

UNIVERSAL CITY

WESTHILLS

SAN PASQUAL

SOUTH MONROVIA ISLANDS

SANTA MONICA MOUNTAINS NORTH AREA

EAST PASADENA - EAST SAN GABRIEL

WILLOWBROOK

LYNWOOD ISLAND

TWIN LAKES

BANDINI ISLANDS

ANTELOPE VALLEY

EAST COMPTON

Legend

Minor Waterways

Major Waterways

Major Road

Los Angeles River Watershed

County TMDL Implementation Areas

Fecal Coliform (#/ac/yr)

1.60e+009 - 1.21e+010

1.22e+010 - 3.53e+010

3.54e+010 - 5.84e+010

5.85e+010 - 1.32e+011

1.33e+011 - 3.25e+0110 4 82 Miles

0 4 82 Kilometers

PacificOcean

VenturaCounty

OrangeCounty

% Los AngelesCounty

50

BMP Development and Engineering Services

Evaluating feasibilityof sites for BMPs

GIS screening

Comparison to prioritypollutant source areas

Field investigations

BMP Development and Engineering Services

Conceptual design

Understanding of thedrainage area

Flow

Pollutant loading

Opportunity for integration ofmultiple benefits

Linkage to existing stormdrain system

LOS ANGELES

COUNTY

LYNWOOD

SOUTH GATE

COUNTY

HUNTINGTON PARK

COUNTY

COUNTY

COMPTON

BELL

VERNON

COMPTON

VERNON

COUNTY

CUDAHY

COUNTY

I105

NAD_1983_StatePlane_California_V_FIPS_0405_FeetMap produced 11-17-2009 - E. Moreno

Legend

Freeways

City Boundaries

BMP Site

BMP Watershed

0 0.5 10.25Miles

0 10.5Kilometers

Mona ParkPotential Centralized BMP & Watershed Area

(FLORENCE-FIRESTONE)

(WILLOWBROOK)

(WALNUT PARK)

51

Los Angeles County TMDL Implementation Plans

Assessment of existing stormwater program elements andprocedures

A: 7.5%

B: 17.2%

C: 18.6%

D: 30.0%

E: 50.0%

F: 70.0%

G: $761.7 Mil

0%

10%

20%

30%

40%

50%

60%

70%

80%

$0 $500 $1,000 $1,500 $2,000 $2,500 $3,000 $3,500

Cost above Baseline Non-structural BMPs ($ Million)

Pe

rce

ntR

ed

uctio

n(C

op

pe

rL

oa

d)

Copper TMDL Target

Scenario 1

Scenario 2

Scenario 3

Selected Points of Interest

Alternative TMDL Solutions


52


• Conceptual designs• Quantified benefits• Considerations for

implementation• Infiltration• O&M

• Costs

Questions

approaches for selecting bmps and estimating their performance · approaches for selecting bmps and...

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