Space Efficient BMP Design for Urban
Stormwater Management
Geoff Mok
Stormwater Consultant
Vaikko P. Allen II, CPSWQ, LEED-AP
Director - Stormwater Regulatory Management
CONTECH Engineered Solutions
Phone: 310-850-1736
vallen@conteches.com
www.contech-cpi.com
CONTECH Engineered Solutions
Phone: 310-850-1736
vallen@conteches.com
www.contech-cpi.com
2014 Montana Stormwater Conference
April 9th, 2014
Billings, Montana
www.ContechES.com
Agenda
1. Regulatory Discussion
o BPSOU Project
2. Defining LID & Design Hierarchy
3. Run-off Reduction & WQ Treatment Methods
o
Reasons for Moving Underground
4. Underground Design Options
o In-depth Look at BPSOU Project
o In-depth Look at Walgreens – Butte & Eisinger Motors - Kalispell
5. Questions & Discussion
www.ContechES.com
Regulatory Drivers for Post Construction
Stormwater Management
 2010 Statewide Phase II permit requires local stormwater
ordinances to be adopted by 2012 requiring retention of the
0.5 inch, 24-hour design storm with LID BMPs where feasible
 Design storm targets may be larger locally
o Whitefish and Kalispell use 1.1 inch storm
 Hydrodynamic Separators are often used where retention isn’t
feasible and are usually sized to achieve 80% TSS removal
o Washington Dept. of Ecology Pretreatment Use Level Designation
widely used as a performance verification reference
 Filters are used where dissolved or fine particulate pollutants
are targeted
www.ContechES.com
LID IS AN APPROACH
GREEN INFRASTRUCTURE
ELIMINATES RUNOFF
TREAT STORMWATER
AS A RESOURCE
MAINTAIN HYDROLOGIC
FUNCTION
www.ContechES.com
CONTECH Design Hierarchy
www.ContechES.com
Detention / Infiltration Design
Pre-developed runoff
Developed Runoff
Pre-developed
runoff
Detention / Infiltration
www.ContechES.com
Infiltration BMPs – A Unit
Process Approach
 Detention or Ponding
 Treatment
o
Removal of pollutants through physical, chemical and biological
processes
 Infiltration
o
Dissipation of water into native soil
www.ContechES.com
Landscape Based Infiltration




Pervious Pavement
Bioretention
Infiltration Basin
Infiltration Trench
www.ContechES.com
Permeable Hardscape
Benefits:
•
•
•
•
A “cornerstone” BMP for LID and Green Infrastructure
Infiltration reduces runoff and pollutant export
Reduction in surface ponding
No dedicated landscaping required
Challenges:
•
•
•
•
•
Cost
Installation QA/QC
Cold climate issues
Maintenance and Longevity
Spill control and pretreatment
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
What is the Difference?
Bioretention
Infiltration
Biofiltration
Flow through Treatment
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
What is the Difference?
Bioretention
Infiltration
Biofiltration
Flow through Treatment
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
Current Bioretention Practice
 Horizontal bed filtration
◦
◦
◦
◦
Pollutants trapped on media surface
Limited head pressure
< 20:1 filter area to land space ratio
Submerged plants
 Open Design
◦ Aesthetics – pollutants/trash exposed
◦ Dedicated land area
 Inlet/Outlet design
◦ Low slope inlets, prone to clogging
◦ Overflow in media bed – prone to washout
 No Flow Control
◦ Oversizing as safety factor
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
Challenges: Gross Pollutants
Challenge
• >5 mm - trash and debris
– Organic matter (Leaves, bud shatter,
landscaping materials)
– Trash
• >500 microns - coarse sediment
– Pavement abrasion, sand, organic
fragments
Impact
• Clogged inlets
• Premature bypass
• Slower infiltration rates
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
Challenges: Horizontal Bed
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
Challenges: Inlet Design
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
Challenges: Outlet Design
www.ContechES.com
© 2012 Contech Engineered Solutions LLC
Challenges: Winter Weather
www.ContechES.com2
© 2012 Contech Engineered Solutions LLC
UrbanGreen™ BioFilter
 Physical filtration and
biological treatment remove
TSS and nutrients
 Infiltrating design equals
bioretention performance in
small footprint
 Meets site aesthetics and
regulatory goals
www.ContechES.com
Urban Green BioFilter Operation
1.
Runoff Reduction:

Evapotranspiration of dry weather
runoff and small storms

Infiltrating vault design and
downstream infiltration chambers
mimic bioretention water balance
2.
Biofiltration:

> 90% removal of silt particles
(d50 < 25 um)
3.
Optional Media Filtration:

4.
StormFilter cartridges can be specified
to increase treatment flow rate
Bypass:

Peak events are bypassed upstream
of the treatment bays
www.ContechES.com
UrbanGreen BioFilter – Longview, WA
Analyte
SSC
TSS
Total Zinc
Soluble Zinc
Total Copper
Mean
In
mg/L
94
88
ug/L
118
43.8
10
Mean
Out
mg/L
15
13
ug/L
18
10.4
2.8
Removal
Efficiency
(%)
84.6
85.2
85.2
76.2
72.0
Median
In
mg/L
70.1
59
ug/L
81.7
34.5
6.4
Median Removal Summation
Out
Efficiency of Load
mg/L
(%)
(%)
8.5
87.9
85.6
8
86.4
85.2
ug/L
12.1
85.2
85.2
7.68
77.7
76.3
2.5
60.9
72
www.ContechES.com
Maverik Convenience Store
UrbanGreen BioFilter and ChamberMaxx Infiltration
Mead, WA
Design Challenges
• Meet stringent water
quality standards and runoff
reduction requirements
• Maximize usable land area
• Meet aesthetic goals for the
site with “green” solutions
Solution
• UrbanGreen BioFilter 6’x8’ met
water quality requirements
• ChamberMaxx infiltration
systems reduced runoff
• The tree selected matched site
landscaping design
Support
Outcome
• Product sizing and
• The entire system was
configuration design
installed in just two days
• Specifications
• The complete system
• Contract drawings
achieved Low Impact
• Installation guidance
Development goals
www.ContechES.com
Subsurface Infiltration
Maximize useable land
Minimize liability
Eliminate vector and wildlife control problems
www.ContechES.com
Subsurface Infiltration Systems
 Infiltration Trench
 Infiltration Gallery
 Drywell
www.ContechES.com
Infiltration trench
 Simple design that requires a lot of stone
 Inefficient use of space at 30-40% voids, adjacent
grass strip or swale and dedicated land area
www.ContechES.com
Infiltration Gallery
www.ContechES.com
Urban Trash Capture
www.ContechES.com
Pre-Treatment Options
Fine particles will clog the infiltrating surface over time
 Biofiltration - Removes particles ≥5 µm
 Media Filtration – Removes particles ≥10 µm
 Hydrodynamic Separation – Removes particles ≥ 50 µm
www.ContechES.com
METAL
Corrugated Metal Pipe
(CMP)
CONCRETE
CON/SPAN
PLASTIC
DuroMaxx
ChamberMaxx
www.ContechES.com
Detention Project #1
Eisinger Motors
In
Kalispell
www.ContechES.com
Eisinger Motors
www.ContechES.com
Eisinger Motors
www.ContechES.com
Eisinger Motors
www.ContechES.com
Eisinger Motors
www.ContechES.com
Detention Project #2
Walgreens Store
In
Butte
www.ContechES.com
Walgreens Project
www.ContechES.com
Walgreens Project
28”x20” Arched Pipe
www.ContechES.com
Walgreens Project
METAL
Corrugated Metal Pipe
(CMP)
CONCRETE
CON/SPAN
PLASTIC
DuroMaxx
ChamberMaxx
www.ContechES.com
Walgreens Project
www.ContechES.com
Walgreens Project
www.ContechES.com
Walgreens Project
www.ContechES.com
Detention / Infiltration Design Tools






DYODS
HydroCAD Stormwater modeling software
Stage storage curve calculator
Land value based calculator
CMP durability documented performance
Team of engineers to assist you on your project
www.ContechES.com
UrbanGreen™ Rainwater Harvesting


Flexible runoff reduction
solution
Integrated turnkey
package systems
• Pretreatment
• Storage
• Pump, treatment and
control systems
Up to 10 LEED® points
for water harvesting!
www.ContechES.com
Systems: Pretreatment, Cisterns, Mechanical Treatment








Large treatment capacity
Full capture
100% capture of harvested water
Non-clogging
Wall mounted or Underground
On-line and off-line options
Economical
Easy maintenance
www.ContechES.com
Systems: Pretreatment, Cisterns, Mechanical Treatment
 Permanent watertight storage
 Exceed project design life
 Calming inlet
 Below ground
 Designed for loading (H20)
 Access for maintenance
www.ContechES.com
Systems: Pretreatment, Cisterns, Mechanical Treatment
Location

Indoor or outdoor enclosure
Make-up water


Mechanical refill
Automatic switch to municipal
Pumps – variable speed


Constant pressure, save energy
Submersible is most common
Controls




Basic protection – prevent pump damage
Standard treatment – automatic controls
Water management – remote monitoring and water info
Treatment
www.ContechES.com
On-online RWH Resources
RWH Video
 Runoff reduction SW permitting
 Water conservation
 Financial savings
 Conteches.com, YouTube
Rainwater Harvesting Runoff
Reduction Calculator™ tool
Enter basic site info to…
 Calculate runoff reduction
 Water conservation
 Financial savings
 Conteches.com
www.ContechES.com
Alta Vista Rainwater Harvesting
Redondo Beach, CA
Design Challenges
 Dry weather base flow
 High pollutant loading
 Large volume watertight storage
CDS Pretreatment
145,000 gallon
UrbanGreen
SRPE Cistern
StormFilter Pretreatment
Solution
 CDS and StormFilter pretreatment
 Two SRPE Cisterns, 145,000 gal
storage
 Capture and treat base flow
 Irrigate city park
Support
 Pretreatment design
 Custom layout to fit site restraints
 Hydraulic analysis
 On-site installation support
Outcome
 Reduction of beach closures
 Reduced potable water demand
www.ContechES.com
Stormwater Management StormFilter:
Designed for Flexibility and Longevity

Extensive lab and field testing and highest approval level with
NJDEP, WADOE and many other agencies

Cartridge height options of 12”, 18”, and 27” accommodate
various hydraulic drop conditions

Customized media options target TSS, Phosphorus, heavy
metals and hydrocarbons

Controlled flow rates through entire media column using siphon
actuated filtration extends media life

Cartridge hood separates media from floating grease and gross
pollutants, further increasing longevity
www.ContechES.com
Evolution of Filter Technology:
Horizontal to Radial
 Increased longevity
 Smaller structures
 Easier maintenance
 Custom filter media options
Horizontal Bed Filter
Manhole StormFilter
www.ContechES.com
StormFilter Media
PhosphoSorb
™
Sediments
■
Phosphorous
■
Oil and
Grease
■
Soluble
Metals
■
Perlite
CSF®
Leaf Media
ZPG
■
■
■
■
■
Organics
Nutrients
■
■
■
■
■
■
■
■
■
■
www.ContechES.com
StormFilter – Proven Technology
 140,000+ cartridges installed over the last 20 years
 Extensive lab and field testing to most stringent protocols
• Technology Assessment Protocol – WADOE (TAPE)
o Evaluated 33 storms in the field
o Achieved State of Washington Department of Ecology General Use
Level Designation for basic treatment
• Technology Acceptance and Reciprocity Partnership (TARP): Tier 1
(lab) and Tier II (field) protocol completed and verified
o Achieved State of New Jersey, Department of Environmental Protection
Final Certification: Standalone BMP
• Additional approval criteria and/or 3rd party lab and field testing
requirements met including MD, NC, VA, TN, NY, TX, MO, CA, NV,
OR, CO, OH, GA, ME and many others nationally and internationally
www.ContechES.com
Filtration Project
BPSOU - Phase II
Project In
Butte
www.ContechES.com
BPSOU – Phase II
Goal = Metals Removal
Reason for Underground
Design
– No Infiltration & Limited
Space
www.ContechES.com
BPSOU Phase II
www.ContechES.com
Jellyfish® Filter Introduction

High surface area membrane filtration

Field tested per TARP protocol and NJDEP
approved for 80% TSS removal at 80gpm per
54” cartridge

Typical driving head: 18 inches

Compact system decreases installed cost and
site footprint

Easy to inspect & maintain
◦ Fewer cartridges
◦ Lightweight cartridges
◦ Backwashed after each storm peak
www.ContechES.com
Jellyfish® Filter Components
Maintenance Access Wall
(MAW)
Hi-flo Cartridges &
Backwash pool
Draindown cartridge
Jellyfish Filter cartridges
Separator skirt
www.ContechES.com
Jellyfish® Filter Operation
3 functions in 1 system
Pretreatment
Filtration
Passive Backwash
Cartridge
www.ContechES.com
Hydrodynamic Separation

Targets suspended solids, oils and trash

Ideal for pretreatment and retrofit applications

Accepted as stand-alone treatment in some regulatory
jurisdictions

Manhole or vault configurations available to accommodate
varying site conditions

Internal or external high flow bypass allows inline or offline
designs

Lab and 3rd party field testing, approved by WADOE,
NJDEP and many others
www.ContechES.com
Hydrodynamic Separation

Captures and retains
100% of trash and debris

Shallow system
profile for easy
installation
VortSentry® HS

Internal bypass simplifies
installation
www.ContechES.com
Knowledge. Solutions.
Service.
Sedimentation Tank
HDS Fundamentals

Low velocity vortex action
•
•

Flow controls
•
•
•

Increases efficiency by increasing length of
flow path
Concentrates solids in low velocity flow field
Minimizes turbulence and velocity
Prevents flow surges and re-suspension
Retains floating pollutants
Maintenance
•
Pollutants are captured in an easily
accessed structure
www.ContechES.com
Key Features and Benefits:

Multiple options to meet site-specific needs
•
Inline, offline, grate inlet and drop inlet
configuration
•
Accepts multiple pipe inlets and 90-180 degree
angles – eliminate the need for junction
manholes
•
Internal and external peak bypass options
available
 Excellent pollutant retention
•
Isolated storage sump eliminates scour potential
•
Oil baffle improves hydrocarbon removal
 Proven performance
•
Performance verified by NJCAT, WA Ecology
and 3rd party verified lab and field tests
www.ContechES.com
Direct Screening
CDS Indirect Screening
4700-MICRON
Key Features and Benefits:

2400-MICRON
One-of-a-kind screening technology
• Captures and retains 100% of floatables and
neutrally buoyant debris 2.4mm or larger
• Effectively removes solids down to 100um
• Self-cleaning-screen – the only non-blocking
screening technology available
• Water velocities within swirls chamber
continually shear debris off the screen to
keep it clean
• Various screening apertures available
www.ContechES.com
HDS Project
BPSOU Project
In
Butte
www.ContechES.com
BPSOU
Soil Contamination = No Infiltration
www.ContechES.com
BPSOU
www.ContechES.com
BPSOU Project
www.ContechES.com
BPSOU Project
www.ContechES.com
Complete Performance Standards
Performance standards preferably include:
 Pollutants of interest
 Probabilistic performance level
o
Preferably addressing both removal efficiency and effluent concentration
 Conditions under which the performance standard must be met
o Water quality design storm (flow or volume based)
o Average annual load reduction
 Should include operation and maintenance feasibility criteria
Clear performance specifications safeguard against a downward spiral of
price based sizing
 Multiple opportunities for “value engineering” in project life cycle can
reduce SCM cost and effectiveness
www.ContechES.com
Design Your Own Hydrodynamic Separator
 Input design criteria to
select the appropriate HDS
unit(s) for your site
◦ Select appropriate unit based on
sight constraints
◦ Size unit based on multiple
mean particle size and targeted
removal percentage
◦ Localized rainfall data provided
◦ Pdf report includes performance
calculations, specification and
standard drawing for the unit that
was sized
Quickly prepare designs for estimates/project meetings
and be more efficient with billable time
www.ContechES.com
Leader in Engineered Solutions!
Supporting Every Stage of Your Project
Solution
Development
Design Assistance
Installation
 Customized Designs – Tailored to fit your unique site requirements
 Unique Value Proposition – Offering speed of construction and overall project savings
 Highly Trained Team of Professionals – Unrivaled technical support for your project
 Local Support – Coverage across U.S., Canada, Mexico, Central America, China & Australia
 Proven Track Record – Over 100 years of demonstrated company and product performance
Highway | Airport | Railway | Mining | Military | Energy
Agriculture | Industrial | Commercial | Municipal | Rehabilitation | Residential
www.ContechES.com