MARC BMP Manual Training Module 1

2008-2009 Training Presentation

1. 1
BMP Training Module 1
BMPs 101
Sponsored by: MARC
Presenters:
Andy Sauer, P.E. (CDM)
Brenda Macke, P.E. (CDM)

November 14, 2008

2. 2
Agenda
8:30-9:30 Lecture 1: BMP Manual Overview
History
Definitions
Basic BMP Principles
BMP Evaluation Process
BMP Manual Future Updates
9:40-10:30 Lecture 2: BMP Level of Service, BMP Selection and BMP Value
Rating
Review the level of service process
Discuss BMP Selection
Level of service and BMP value rating examples
Treatment train
10:30- 11:00 Activity
11:10 – 11:50 Lecture 3: BMP Hydrology & Introduction to BMP Design
Water Quality Volume
90% Rainfall Event
Methods for calculation
11:50 – 12:00 Lecture 4: Regional Initiatives

3. 3
Lecture 1 BMP Overview
History

Definitions of BMP

Basics BMP Principles

BMP Evaluation Process


BMP Manual Future Updates






Kansas City MO

4. 4
History of BMP Manual
City of Lenexa 2001
Revised 2003 for MARC/APWA project
Final form adopted 2004 as a APWA
technical reference
Utilizes TR-55 Method
Commonly used
Well documented
Updates – APWA Water Resources BMP
Subcommittee (2005- 2007)
Updated BMP Manual – March 2008

5. 5
History of BMP Manual
Level of Service Approach
Updates Started in January 2005
BMP Subcommittee of APWA
March 2008 Manual Update
Future Manual Updates
Treatment Train Table
Redevelopment LOS Requirements
Pervious Pavement Design Guidelines
Vegetated Filter Strip Design Guidelines
More Design Examples

6. 6
Poll Question No. 1
How many have used, or are familiar with, the
current MARC BMP Manual (March 2008)?

Used it for a project ______
Review it, and used it as a guide _____
Familiar with the manual but never applied it _____
Attended a training on the manual _____
Never heard of it ________

7. 7
Why we need a BMP
Manual?
1972 National Pollutant Discharge System
(NPDES) established Under the Clean Water Act
1990 EPA issued the Phase I Stormwater Rule
Required NPDES permit for municipalities over
100,000
Municipal Separate Storm Sewer Systems (MS4s)
1999 EPA issued the Phase II Stormwater Rule
Extended the NPDES to smaller communities <
100,000 (10,000 & 100,000)
NPDES permits required communities to develop a
program to reduce runoff pollutants from new
development and redevelopment sites

8. 8
What is a BMP or green
solution?
EPA definition: BMPs can include planning,
schedules of activities, prohibitions of
practices, maintenance procedures, and other
management approaches necessary to
prevent or reduce the pollution of waters of
the United States

WERF definition: BMPs attempt to mimic
drainage patterns of the natural watershed
and provide some treatment to improve
quality of the water discharged

9. 9
What is a BMP or green
solution?

MARC manual: Stormwater
management practice used
to prevent or control the
discharge of pollutants and
minimize runoff to waters of
the U.S. BMPs may include
structural or non- structural
solutions, a schedule of
activities, prohibition of
practices, maintenance
procedures, or other
management practices.

Seattle’s street edge alternatives program
(www.lowimpactdevelopment.org)

10. 10
Best Management Practice
(BMP)
Best – State of the Practice
No definitive answer
Past experience, testing, research,
Unique to site
Management – Responsible Parties
Improve water quality, meet NPDES Phase II
Jurisdictional specific
Meet specific requirements of a regional
Practice – Action or Implementation
Practice = defined to carry out, apply, or to
do or perform often.

11. 11
Basic BMP Principles
Plan for stormwater management
Sustainable and “be green”
Provide a level of service
Improve water quality
Mimic natural hydrology
Increase initial abstraction
Promote infiltration, retention & ET
“Treat” the stormwater runoff
Natural processes
Treatment trains

12. 12
Basic BMP Principles

PLAN
MIMIC
TREAT

13. 13
Non-Structural BMPs
Preserving native vegetation, existing filtration
and infiltration capacity is the most cost
effective and efficient method of treatment


http://cfpub.epa.gov/npdes/stormwater/menuofbmps/index.cfm
PLAN

14. 14
Minimize Development
Impacts
Minimize grading
Minimize soil compaction
Minimize tree removal
Reduce impervious
surfaces
Reduce road widths
Cluster buildings
Reduce building
footprints
PLAN

15. 15
Preserving Natural
Hydrology, Infiltration
Capacity
Management/Awareness
Community education
Revise planning and development codes
•Stream buffer width
•Housing density
•Street width
Low Impact Development (LID)
Preserve existing open space, native
vegetation
Pervious landscaping
Disconnect impervious cover
Prevent soil compaction

PLAN

16. 16
Preserving Natural
Hydrology, Infiltration
Capacity
Low Impact Development Center
PLAN

17. 17

PLAN

18. 18
BMP Evaluation Process
Mid-Level
PLAN
MIMIC
TREAT

19. 19
Engineered Stormwater
Treatment & Infiltration
Capture runoff near the source (Lot Level)
Downspouts
Driveways
Infiltration
Engineered sub-grades
Native plants
Soil Enhancements
Evapotranspiration (ET)
Plant usage
Can be significant
Detention/Retention

MIMIC

20. 20
Treatment and Infiltration
Structural BMPs filter and detain
runoff
Infiltration basins, trenches
Bioretention cells
Vegetated swales
Raingardens
On site
A combination of
structures may be
necessary


Topeka KS
MIMIC

21. 21
Engineered Stormwater
Treatment & Infiltration
Seattle’s street edge alternatives program
(www.lowimpactdevelopment.org)
MIMIC
University of Missouri at Kansas City / CDM

22. 22
Treatment and Infiltration:
Rain Gardens
Large number being
installed locally
Infiltration and
evapotranspiration
from plants
More green than gray
Minimal engineering

Decentralized






10,000 Raingardens (www.rainkc.com)
MIMIC

23. 23
BMP Evaluation Process
Lowest Level
Extended detention
(40 hours) to
increase treatment
and decrease peak
flows
PLAN
MIMIC
TREAT

24. 24
Detention and Treatment
Structural BMPs
detain runoff
Extended Detention
Basins
•Wet
•Dry
Extended Detention
Wetlands
Infiltration basins
Typically used as
larger, centralized
facilities
Topeka KS
TREAT

25. 25
Example site
Streambank
Biostabilization
Culvert
Grass Swale
Wet
Pond
Commercial
Building
Bio-
Filters
Design Documents
– APWA 5600
– BMP Manual
– Watershed
Master Plans
TREAT

26. 26
Structural BMP Consideration
Pollutant removal efficiency
Water quality volume
Site suitability
Tributary area
Dimensions (depth, length- width ratio)
Outlet
Emergency spillway
Maintenance easement
Routine and non- routine maintenance

27. 27
Poll Question No. 2
What sector (public or private) do you represent?
Government agencies (city, county, state, or federal) ____
Engineering consulting (development,
design/construction, planning) ______
Non-profit organizations ______
Private citizens _____
Others _____
What is your role?
Planners _____
Design Engineers _____
Reviewer/Approval_____
Constructor _____
Regulator ______

28. 28
BMP Evaluation Process
What are the “best” BMPs?
Evaluation is usually a function of:
Site location (Location, Location, Location)
Receiving water standards or objectives (e.g. TMDL)
Desired aesthetics
Treatment Evaluation
Percent removal
•Function of water quality coming in
•May not be able to meet your water quality objective
Effluent Concentration (MARC Manual)
•Pollutant specific
•TSS has the greatest amount of data

29. 29
BMP Evaluation
General Rule
Aesthetics/Amenity

30. 30
BMP Evaluation

31. 31
BMP Evaluation Process (cont.)
Based on the best available information
Can be adjusted to meet local needs
BMP Evaluated on 4 Criteria
Water Quality Value
•TSS
•Median Expected Effluent EMC
•Source: International Stormwater Best Management
Practices Database (www.bmpdatabase.org)
Volume Reduction
Temperature Reduction
Oil/Floatables Removal

32. 32

33. Removal Efficiency

34. Removal Efficiency

35. Removal Efficiency

36. Removal Efficiency

37. Regional BMP Monitoring
Johnson County Stormwater Management Program
University of Kansas – Ted Peltier
Kansas State University
Stacy Hutchinson – Biological & Ag. Engineering
Alicia Greene – MS Graduate Student
Lee Skabelund - Assistant Professor College of Architecture,
Planning & Design
University of Missouri at Kansas City
Deb O'Bannon – Civil Engineering

MARC – EPA Grant
Ginny Moore

38. Regional BMP Monitoring

39. Regional BMP Monitoring

40. Regional BMP Monitoring

41. EPA Webcast Slide

41

42. EPA Webcast Slide

42

43. EPA Webcast Slide

43

44. 44
BMP Value Rating
4 Goals/Objectives
Reduce Volume
•Infiltration
•Evapotranspiration (ET)
Remove total suspended solids (TSS)
•Settling
Temperature Reduction
•Urban heat island
Remove oils and floatables
•Screening and netting

45. 45
New Value Rating System –
Based on BMP Goals
Condensed Table 5









BMP value table is based on the 4 goals of BMPs
BMP
Median
Expected
Effluent
EMC TSS
Water
Quality
Value
Volume
Reduction
Temperature
Reduction
Oils/Floatables
Reduction
Overall
Value
Vegetation N/A 5.25 2 1 1 9.25
Rain Garden < 10 4 2 1 2 9.0
Infiltration Practices < 10 4 2 1 2 9.0
Bioretention < 10 4 1.5 1 2 8.5
Pervious or Porous Pavement 10 - 20 3 1.5 1 2 7.5
Extended Detention Wetland < 10 4 2 0 1 7.0
Media Filtration Practices < 10 4 0 0 2 6.0
Wetland Swale 10 - 20 3 1 0 1 5.0
Bio-Swale 10 - 20 3 1 0 1 5.0
Extended Wet Detention 10 - 20 3 2 -1 1 5.0
Native Vegetation Swale 10 - 20 3 1 0 0 4.0
Extended Dry Detention Basin 20 - 50 2 1 0 1 4.0
Turf Grass Swale 10 - 20 3 0 0 0 3.0
Value Ratings

46. 46
BMP Goal: TSS Effluent
(Water Quality Value)
Effects of suspended solids
Decrease light penetration
Damage fish gills
Deposits downstream
Impacts aquatic habitat
Particulate removal results in wide range of
pollutant removal
Metals, nutrients, bacteria, oils
Scored 0- 4
+
, >100mg/L to <10mg/L

47. 47
Why use TSS as an indicator
of water quality?
TSS has predominantly been used in the past
monitor BMPs
TSS is relatively easy to measure
TSS can be used as a surrogate to monitor
other contaminants

48. 48
BMP Goal: Volume
Reduction
Replicate predevelopment flow conditions
Not just reduction of peak flow but reduction of
total runoff volume
Reduce velocity and therefore erosive capability
Scored 0- 2
BMP
Percolation/filtration
ET
Outflow
Infiltration
Runoff/inflow Runoff/inflow
Underdrain

49. 49
BMP Goal: Remove Oils and
Floatables
Oils can be toxic to plants and wildlife
Disrupt other treatment processes
Floatables (trash)
Clog hydraulic structures
Eyesore
Contain pollutants
Scored 0- 2

Lenexa KS Lenexa KS

50. 50
BMP Goal: Temperature
Reduction
Runoff from paved surfaces can be
significantly warmer than surface water and
natural runoff
Increased water temperature effects:
Decreased dissolved oxygen capacity
Increases pollutant reaction rates
Increases solubility of many pollutants
Scored -1 to 1, increased temperature to
decreased temperature

51. 51
Questions?

Comments.

52. 52
Break (10 minutes)

53. 53
Lecture 2: BMP Level of
Service and Value Rating
System
Topeka KS
Hancor Inc.
Kansas City MO

54. 54
BMP Selection Flowchart
Level Of Service
BMP Value Rating
Water Quality
Volume/sizing
Placement
Maintenance

55. 55
Level of Service
Step 1 – Determine Pre- Development
Conditions
Step 2 – Determine Post-Development
Conditions
Step 3 – Calculate the difference . . .
. . . This is the level of service

56. 56
Level of Service
Level of Service: Rating the predevelopment
condition of the site and determining what
treatment system will, at a minimum maintain
that condition

Step-by-step
procedure in
BMP manual

Kansas City MO

57. 57
Pre-Development
Insert an aerial photo of an undeveloped
area

58. 58
Level of Service
Previously Undeveloped
Predevelopment curve number (CN) Vs. post
development CN

Area weighted CN = Σ (CN
i * Area
i) / Total Area

Area weighted CN
post – Area weighted CN
pre

Procedure for calculating individual CN is
detailed in Table 1, p. 27 in the BMP manual

59. 59
Level of Service
Previously Undeveloped
* Does not meet APWA 5600 definition of “Development”; applies
only where more stringent local requirements are in effect

Change in CN Impact Level of service
17 or greater High water quality impact 8
7 to 16 Moderate water quality impact 7
4 to 6 Low water quality impact 6
1 to 3 Minimal water quality impact 5
0 Negligible 4*
-7 to -1 Minimal water quality improvement 3*
-8 to -17 Low water quality improvement 2*
-18 to -21 Moderate water quality improvement 1*
-22 or less High water quality improvement 0*
Table 2, p. 28

60. 60
Level of Service
Redevelopment
% impervious surface of existing site vs. % impervious
surface of proposed site
Developed sites are grouped into 4 ranges
•Range #1 = <12%
•Range #2 = 12- 25%
•Range #3 = 25- 65%
•Range #4 = >65%
Level of service is base on increase in range
Increase in Range # = Range#
(proposed) – Range#
(existing)

Tables 3 and 4 in manual

61. 61
Level of Service
Redevelopment
Increase in range
of
%imperviousness Impact
Level of
Service
+3 High water quality impact 7
+2 Moderate water quality impact 6
+1 Low water quality impact 5
None Negligible water quality impact 4*
-1 Low water quality benefit 3*
-2 Moderate water quality benefit 2*
-3 High water quality benefit 1*
* Does not meet APWA 5600 definition of “Development”; applies
only where more stringent local requirements are in effect

62. 62
Future Manual Updates:
Level of Service
Redevelopment

APWA water resources BMP subcommittee
Evaluated current calculation
Proposing a revision

Revision must be approved before becoming a part of
the manual.

63. 63
Poll Question No. 3
Who has calculated a level of service for a previously
undeveloped site?


Who has calculated a level of service for a
redeveloped site?

64. 64
Post Development BMP
Selection
The area weighted value rating (VR) of the
site must equal or exceed the level of service
(LS)
This includes all BMPs for a given site
Can be a combination of various BMPs
Determine value ratings for each BMP using
Table 5 in Section 4 of manual

65. 65
Post Development BMP
Selection

66. 66
Post Development BMP
Selection
Calculate the Area weighted average of the VR

Area weighted VR = Σ (VR
i * Area
i ) / Total Area

Area weighted VR ≥ LS

If the VR does not satisfy the LS requirement
an adjustment of the design will have to be
made

67. 67
Previously Undeveloped Site
Example
10 acres of undeveloped farm land




Acres Cover type Condition
6 Fallow Crop,
residue
Good
3 Woods Good

1 Brush Fair

68. 68
Use the NRCS soil survey website to find the
HSG
http://websoilsurvey.nrcs.usda.gov








For this example: HSG for silty loam is B

Previously Undeveloped Site
Example

69. 69
Using Table 1 in BMP manual to find the CN
for each cover type:






Finding the area averaged CN:

CN
avg = (6*83+3*55+1*48)/10 = 71
Acres Cover type Condition HSG CN
6 Fallow Crop,
residue
Good B 83
3 Woods Good

B 55
1 Brush Good B 48
Previously Undeveloped Site
Example

70. 70
10,000 Raingardens
(www.rainkc.com)
Previously Undeveloped Site
Example – BMP Design
Option 1
8 acres of ¼ acre lot residential
Rain gardens for each lot (32 Rain gardens)
Each rain garden can capture ¼ of the lot area
Street runoff directed to 4 rain gardens
1 acre of native vegetation preserved or
established

71. 71
Development plan:








Note: Postdevelopment HSG is assumed to be one group
higher then predevelopment unless a soil treatment plan is
provided

Area Cover type HSG CN
8 ac 1/4-acre residential
lots

C 83
1 ac Streets NA 98
1 ac Native grass, shrubs
(informal)
B (using soil preservation method
in appendix A)

48
Previously Undeveloped Site
Example – BMP Design
Option 1

72. 72
Post Development area averaged CN:
CN
avg = (8 ac * 83) + (1 ac * 98) + (1 ac * 48) / 10 ac = 81

Change in CN

CN
change = 81- 71 = 10

Level of service = 7




Previously Undeveloped Site
Example – BMP Design
Option 1

73. 73
BMP plan:









Area Cover type BMP Treatment
Area
Value
Rating
8 ac 1/4-acre
residential
lots

Rain Garden for
each lot
32 Rain Gardens
Treat ¼ of the lot
2 ac 9.0
1 ac Streets Rain Garden to
capture street
runoff
4 Rain Gardens
1 ac 9.0
1 ac Native
grass,
shrubs
Preserve or
Establish Native
Vegetation
1 ac 9.25
Previously Undeveloped Site
Example – BMP Design
Option 1

74. 74
Option 1
Area averaged VR:

VR
avg = (2 ac* 9.0) + (1 ac * 9.0) + (1 ac * 9.25) / 10 ac = 3.63

Does not meet the required level of service of 7
How many rain gardens would it take to meet level of
service?
Lot rain gardens would need to treat 5.75 ac (72%)
3 rain gardens per lot
Incorporated into HOA covenant
Design
Maintenance







Previously Undeveloped Site
Example – BMP Design
Option 1

75. 75
4 acres of 1/8 acre lot residential
2.2 acre of native vegetation preserved or
established
3 acre of wooded vegetation preserved






Previously Undeveloped Site
Example – BMP Design
Option 2

76. 76
BMP Plan







Area Cover type HSG CN
4 ac 1/8-acre residential lots

C 90
2.2 ac Native grass, shrubs
(informal)
B (using soil preservation method in
Appendix A)

48
3 ac Woods B 55
0.8 ac Street NA 98
Previously Undeveloped Site
Example – BMP Design
Option 2

77. 77
Post Development area averaged CN:
CN
avg = (4 ac * 90) + (0.8 ac * 98) + (2.2 ac * 48) +
(3 ac * 55) / 10 ac = 71

Change in CN

CN
change = 71- 71 = 0

Level of service = 4




Previously Undeveloped Site
Example – BMP Design
Option 2

78. 78
Previously Undeveloped Site
Example– Option 2
BMP plan:









Area Cover type BMP Treatment
Area
Value
Rating
4 ac 1/8-acre
residential
lots
No BMPs 0 ac 0
0.8 ac Streets No BMP 0 ac 0
3.0 Woodland Preserve 3.0 ac 9.25
2.2 ac Native
grass,
shrubs
Preserve or
Establish Native
Vegetation
2.2 ac 9.25

79. 79
Option 2: Higher Density with Woodlands & Native Vegetation
Area averaged VR:

VR
avg = (3 ac* 9.25) + (2.2 ac * 9.25) / 10 ac = 4.8



Exceeds the required level of service of 4
Portion of site not treated by a BMP






Previously Undeveloped Site
Example – Option 2

80. 80
VR Increase by Combining
BMPs
Selecting multiple BMPs with complementary treatment
mechanisms can increase the value rating

81. 81
Treatment train (VR
TT* A
TT)
Wetland Swale
Extended Wet Detention (0.5 ac)
Table 6 for VR
Preserve 1 ac of native area


VR Increase by Combining
BMPs

82. 82
VR Increase by Combining
BMPs
VR = 9.5

83. 83

7.5 acres of ¼ acre lot residential
Runoff enters wetland swale to 0.5 acre Extended
Wet Detention Basin
1 acre of native vegetation preserved or
established


Previously Undeveloped Site
Example – BMP Design
Option 3

84. 84
Development plan:








CN = 82; 82-71 = 11 for a LS = 7
Note: Postdevelopment HSG is assumed to be one group
higher then predevelopment unless a soil treatment plan is
provided

Area Cover type HSG CN
7.5 ac 1/4-acre residential
lots
C 83
1 ac Streets NA 98
0.5 ac Extended wet
detention
NA 98
1 ac Native grass, shrubs (informal) B (using soil preservation method
in appendix A)
48
Previously Undeveloped Site
Example – BMP Design
Option 3

85. 85
BMP plan:









Area Cover type BMP Treatment
Area
Value
Rating
7.5 ac 1/4-acre
residential
lots
Wetland Swale to
Extended Wet
Detention
7.5 ac

9.5
0.5 ac Extended
wet
detention
Extended Wet
Detention
0.5 ac

5.0
1 ac Streets No BMP 0 ac 0
1 ac Native
grass,
shrubs
Preserve or
Establish Native
Vegetation
1 ac 9.25
VRavg = (7.5 ac* 9.5) + (0.5 ac * 5) + (1 ac * 9.25) / 10 ac = 8.3
Previously Undeveloped Site
Example – BMP Design
Option 3

86. 86
Previously Undeveloped /
Redevelopment Site
Examples
Detailed examples and
worksheets in BMP manual

87. 87
Woods
Fair Condition
HSG B
Area = 3 Ac
Contoured Crops
Good Condition
HSG B
Area = 19 Ac
Contoured Crops
Good Condition HSG B Area = 8 Ac
Total Site = 30 Acres
A
B
Activity – Level of Service

88. 88
Answer Key – BMP Option 1

89. 89
Answer Key – BMP
Package1/2/3

90. 90
Answer Key – BMP Package 1
B.Postdevelopment CN
Cover Description Soil HSG
1
CN from
Table 1Area (ac.)
Product of
CN x Area
A - 1/3 Acre Lots C 81 2.10 170
A - 1/4 Acre Lots C 83 4.40 365
A - Streets (Curb & Gutter) NA 98 1.42 139
B - 1/3 Acre Lots C 81 4.43 359
B - 1/4 Acre Lots C 83 13.20 1096
B - Streets (Curb & Gutter) NA 98 3.25 319
Extended Wet Detention BasinNA 98 1.20 118
Totals: 30.00 2565
1
Postdevelopment CN is one HSG higher for all cover types except preserved vegetation,
absent documentation showing how postdevelopment soil structure will be preserved.
Area-Weighted CN = total product/total area = 86 (Round to integer)
C.Level of Service (LS) Calculation Change in CN LS
Postdevelopment CN: 86 17+ 8
7 to 16 7
Predevelopment CN: 74 4 to 6 6
1 to 3 5
Difference: 12 0 4
-7 to -1 3
LS Required (see scale at right): 7 -8 to -17 2
-18 to -21 1
-22 - 0

91. 91
Answer Key – BMP Package 1
WORKSHEET 2: DEVELOP MITIGATION PACKAGE(S) THAT MEET THE REQUIRED LS
Project: Green Acres - BMP Package 1 By: NAP Date: 11/15/2007
Location: Kansas City Metro Checked: BRM Date: 11/12/08
Sheet __ of __
1.Required LS (from Table 1 or 1A or Worksheet 1 or 1A, as appropriate): 7
Note: Various BMPs may alter CN of proposed development, and LS; recalculate both if applicable.
2.Proposed BMP Option Package No. ___
Cover/BMP Description
T reat ment
Area
VR from
Table 5
or 6
1
Product of VR
x Area
A -1/4 Ac. Resid. - native veg. swale 4.40 4.00 17.60
A - 1/3 Ac. Resid - rain gardens 2.10 9.00 18.90
A - Streets - native veg. swale 1.42 4.00 5. 68
B - All Resid - Extended Wet Det. Basin 17.63 5.00 88.15
B - Streets - Extended Wet Det. Basin 3.25 5.00 16.25
B - Extended Wet Detention Basin 1.20 5.00 6. 00
Total
2
: 30.00 Total: 152.58
Weighted VR: 5. 09
1
VR calculated for final BMP only in Treatment Train.
2
Total treatment area cannot exceed 100 percent of the actual site area.
Meets required LS (Yes/No)? NO

= total product/total area

92. 92
Answer Key – BMP Package 2

93. 93
Answer Key – BMP Package 2
B.Postdevelopment CN
Cover Description Soil HSG
1
CN from
Table 1Area (ac.)
Product of
CN x Area
A - 1/3 Acre Lots C 81 2.15 174
A - 1/4 Acre Lots C 83 4.43 368
A - Streets (Curb & Gutter) NA 98 1.42 139
B - 1/3 Acre Lots C 81 2.00 162
B - 1/4 Acre Lots C 83 12.55 1042
B - Woods - Preserved B 60 3.00 180
B - Streets (Curb & Gutter) NA 98 3.25 319
B - Extended Detention WetlandNA 98 1.20 118
Totals: 30.00 2501
1
Postdevelopment CN is one HSG higher for all cover types except preserved vegetation,
absent documentation showing how postdevelopment soil structure will be preserved.
Area-Weighted CN = total product/total area = 83 (Round to integer)
C.Level of Service (LS) Calculation Change in CN LS
Postdevelopment CN: 83 17+ 8
7 to 16 7
Predevelopment CN: 74 4 to 6 6
1 to 3 5
Difference: 9 0 4
-7 to -1 3
LS Required (see scale at right): 7 -8 to -17 2
-18 to -21 1
-22 - 0

94. 94
Answer Key – BMP Package 2
WORKSHEET 2: DEVELOP MITIGATION PACKAGE(S) THAT MEET THE REQUIRED LS
Project: Green Acres - BMP Package 2 By: NAP Date: 11/15/2007
Location: Kansas City Metro Checked: BRM Date: 11/12/08
Sheet __ of __
1.Required LS (from Table 1 or 1A or Worksheet 1 or 1A, as appropriate): 7
Note: Various BMPs may alter CN of proposed development, and LS; recalculate both if applicable.
2.Proposed BMP Option Package No. ___
Cover/BMP Description
T reat ment
Area
VR from
Table 5
or 6
1
Product of VR
x Area
A -1/4 Ac. Resid - native veg. swale 4.43 4. 00 17.72
A - 1/3 Ac. Resid - rain gardens 2.15 9. 00 19.35
A - Streets to native veg. swale 1.42 4. 00 5.68
B - All Res to native veg. swale to EDW 14.55 8. 00 116.40
B - Streets to native veg. swale to EDW 3.25 8. 00 26.00
B - EDW 1.20 7. 00 8.40
B - Woods - preserved 3.00 9. 25 27.75
Total
2
: 30.00 Total: 221.30
Weighted VR: 7.38
1
VR calculated for final BMP only in Treatment Train.
2
Total treatment area cannot exceed 100 percent of the actual site area.
Meets required LS (Yes/No)? YES (If No, or if additional options are being tested,
proceed below.)
= total product/total area

95. 95
Answer Key – BMP Package 3

96. 96
Answer Key – BMP Package 3
B.Postdevelopment CN
Cover Description Soil HSG
1
CN from
Table 1Area (ac.)
Product of
CN x Area
A - 1/3 Acre Lots C 81 2.15 174
A - 1/4 Acre Lots C 83 4.43 368
A - Streets (Curb & Gutter) NA 98 1.42 139
B - 1/3 Acre Lots C 81 2.00 162
B - 1/4 Acre Lots C 83 12.55 1042
B - Streets (Curb & Gutter) NA 98 3.25 319
B - Woods - Preserved B 60 3.00 180
B - EDW NA 98 1.20 118
Totals: 30.00 2501
1
Postdevelopment CN is one HSG higher for all cover types except preserved vegetation,
absent documentation showing how postdevelopment soil structure will be preserved.
(Round to integer)
Area-Weighted CN = total product/total area = 83
C.
Level of Service (LS) Calculation Change in CN LS
Postdevelopment CN: 83 17+ 8
7 to 16 7
Predevelopment CN: 74 4 to 6 6
1 to 3 5
Difference: 9 0 4
-7 to -1 3
LS Required (see scale at right): 7 -8 to -17 2
-18 to -21 1
-22 - 0

97. 97
Answer Key – BMP Option 3
WORKSHEET 2: DEVELOP MITIGATION PACKAGE(S) THAT MEET THE REQUIRED LS
Project: Green Acres - BMP Package 3 By: NAP Date: 11/15/2007
Location: Kansas City Metro Checked: Dat e:
Sheet __ of __
1.Required LS (from Table 1 or 1A or Worksheet 1 or 1A, as appropriate): 7
Note: Various BMPs may alter CN of proposed development, and LS; recalculate both if applicable.
2.Proposed BMP Option Package No. ___
Cover/BMP Description
Treatment
Area
VR from
Table 5
or 6
1
Product of VR
x Area
A -1/4 Ac. Resid. - native veg swale 4.43 4.00 17.72
A - 1/3 Ac. Resid - rain gardens 2.15 9.00 19.35
A - Streets to native veg. swale 1.42 4.00 5.68
B - All Res to EDW 14.55 7.00 101.85
B - Streets to EDW 3.25 7.00 22.75
B - EDW 1.20 7.00 8.40
B - Woods - preserved 3.00 9.25 27.75
Total
2
: 30.00 Total: 203.50
Weighted VR: 6.78
1
VR calculated for final BMP only in Treatment Train.
2
Total treatment area cannot exceed 100 percent of the actual site area.
Meets required LS (Yes/No)? NO
= total product/total area

98. 98
Break (10 minutes)

99. 99
Lecture 3 – BMP Hydrology
& Introduction to BMP
Design

100. 100
Water Quality Volume (First
Flush -> WQv)

Generally considered to be approximately the
first ½ inch of runoff

Runoff from initial rainfall contains the
highest concentration of pollutants

BMPs are designed to treat this “first flush” of
concentrated runoff not extreme flood events

The Water Quality Volume (WQv) includes this
first flush

101. 101
Water Quality Volume (WQv)
Water Quality Volume
(WQv): The storage
needed to capture and
treat 90% of the average
annual storm runoff
volume
Water Quality storm: The
storm event that
produces ≤ 90% volume
of all daily storms in a
year
WQv
WQv = (Precip)*(Runoff coef.)*(Area)

102. 102
Why Use the WQv to size
BMPs?
Retain runoff long enough to get
water quality benefits

Reducing erosive flows from
smaller runoff events

103. 103
Kansas City Water Quality
Storm
Young and McEnroe
2002
Purpose
Revise precipitation
frequency estimates
Evaluate historical
record for trends in
rainfall extremes
Estimate 90% rainfall
event for stormwater
quality management
1.37 inches

http://kcmetro.apwa.net

104. 104
2003 Kansas City Precip events
0
5
10
15
20
25
30
35
40
45
Daily Precipitation (in)
# of days > or=
Kansas City Water Quality
Storm
Water Quality
Storm = 1.37 in
Young and McEnroe
(http://kcmetro.apwa.net)

105. 105
Water Quality Storm Data
Stormwater Manager’s Resource Center
www.stormwatercenter.net
Provides 90% storm for other locations
Young and McEnroe 2002

106. 106
Water Quality Volume
Calculation
Two methods
Short-Cut Method
•Sites < 10 acres
•Only 1 predominant cover type

Small Storm Hydrology Method
•Larger or more heterogeneous drainage
areas

107. 107
WQv Calculation
Short-Cut Method

WQv = P*Rv

P = 24 hour Water Quality Storm (inches)
Rv = Volumetric run coefficient =
0.05+0.009(I)
I = % site Imperviousness

108. 108
WQv Short-cut Example
Given
Tributary area (A
Tributary) = 2.5 acres
%impervious = 80%

WQv = 1.37in * [0.05 + (0.009 * 80%)] = 1.06 in

Multiply by A
Tributary to get volume

1.06 * 1ft/12in * 2.5 acres = 0.22 ac- ft

If only 50% impervious WQv = 0.14 ac- ft

109. 109
WQv Calculation
Small Storm Hydrology Method

WQv = P*Weighted Rv

Weighted Rv = Σ(Rv
i*Ac
i)/Total area (ac)
Rv
i = Volumetric runoff coefficient for
cover type (table)
Ac
i = Area of cover type i (ac)

110. 110
Rv Table
BMP MANUAL SECTION 6, TABLE 5
VOLUMETRIC COEFFICIENTS FOR URBAN RUNOFF
FOR
DIRECTLY CONNECTED IMPERVIOUS AREAS
(CLAYTOR AND SCHUELER 1996)

Rainfall
(inches)
Flat roofs and
large unpaved
parking lots
Pitched roofs and
large impervious
areas
(large parking lots)
Small
impervious
areas and
narrow
streets
Silty
soils
HSG-B
Clayey
soils HSG-
C and D
0.75 0.82 0.97 0.66 0.11 0.20
1.00 0.84 0.97 0.70 0.11 0.21
1.25 0.86 0.98 0.74 0.13 0.22
1.37 0.87 0.98 0.75 0.14 0.23
1.50 0.88 0.99 0.77 0.15 0.24
Note: a reduction factor may be applied to the Rv values for disconnected
surfaces, consult the BMP manual hydrology section

111. 111
WQv Small Storm Example
Given: A
Tributary = 26 ac

Cover Type Rv Area (acres)
Flat roofs 0.87 1.6
Parking lots 0.98 8.8
Narrow streets 0.75 3.3
Silty soil 0.14 12.3
( )
∑ =×
×+×+×+×
=×
×
= inP
AreaTotal
AcRv
WQv
ii
749.037.1
26
3.1214.03.375.08.898.06.187.0
Multiply by A
Tributary to get volume

112. 112
Poll Question No. 4
What types of BMPs have been constructed in this area for
new development?



What types of BMPs have been constructed in this area for
redevelopment?

113. 113
BMPs – Green to Gray

114. 114
Key Points: Vegetation
Native Vegetation Preserved or
Established
Prevent against erosion
Penetration of roots
increases infiltration
Removal of pollutants
and suspended solids
Aesthetic value
Kansas Biologic Survey (www.kbs.ku.edu/)
Miami County, KS

115. 115
Key Points: Vegetation
Native Vegetation Preserved or
Established
Prairie Blazing Star, Liatris pycnostachya
Kansas City MO

116. 116
Natural Resource Inventory (NRI)
Map showing
valuable natural
resource assets
Complete for
Kansas City area
(8 counties)
GIS data and
maps
http://www.marc.org/Environment/Smart_Growth/NRI/index.htm

117. 117
NRI – Jackson County

118. 118
Structural BMP Types
Rain Gardens
Bioretention Cells
Extended Wet Detention Basins
Extended Dry Detention Basins
Extended Detention Wetlands
Infiltration Structures
Porous Surfaces

119. 119
Rain Gardens and Rain Barrels
UMKC Raingarden Project
Topeka KS

120. 120
Bioretention Cells at Mize Lake
Lenexa, KS

121. 121
Bioretention Swales
Neighborhood
Redevelopment
Quinton Heights
Topeka, Kansas

122. 122
Extended Detention
Wetland
Belle Avenue,
Topeka Kansas

123. 123
Extended Wet Detention
Topeka KS

124. 124
Extended Dry Detention

125. 125
Infiltration Basins

126. 126
Porous Pavement
Concrete
Promotions
I’Lan Park Leawood KS

127. 127
Hancor Stormwater Quality
Unit Installation

128. 128
Vortcapture VC-70
Installation

129. 129
What have other
communities done?
BMPs and Green Solution
Experiences from Other Communities Across the Nation
Lenexa - www.raintorecreation.org/index.html
Lincoln - www.lincoln.ne.gov/city/pworks/watrshed/
Philadelphia – www.phillyriverinfo.org/
Detroit – www.rougeriver.com/
Portland – www.portlandonline.com/bes
Milwaukee – www.mmsd.com/home/index.cfm
Chicago - egov.cityofchicago.org/
Pittsburgh – www.ninemilerun.org

130. 130
BMP Maintenance
Private Property
Annual inspection submittals
Tied to HOA
Title Restriction
Public Property
Inspect after each rainfall event > 0.5 inches
Annual inspections
Bi-annual maintenance (replanting and
regrading)
Vegetation Management
Other?

131. 131
Lecture 4 – Regional
Initiatives

132. 132
Other Resources:
MARC Website (http://www.marc.org)

133. 133
Upcoming Training Sessions
Module #2 – Extended Wet Detention & Wetlands
Date: December 12, 2008
Location: Helzberg Auditorium, KCPL
Module #3 – Rain Gardens & Bioretention
Date: January 23, 2009
Location: Helzberg Auditorium, KCPL
Module #4 – Extended Dry Detention & Infiltration
(Pervious Pavements)
Date: February 20, 2008
Location: Helzberg Auditorium, KCPL

134. 134
Questions?

Comments.

Suggestions.