A sustainability rating system for roadways
Steve Muench
University of Washington
1
What we mean by “sustainability”
What a Greenroad looks like
Greenroads description
Example credits
Why bother?
2
What we mean by “sustainability”

There are a lot of definitions for “sustainable” out there. Most are
incomplete. This is what we think “sustainability” means.
Sustainability is a system characteristic which refers to the
system’s capacity to support natural laws and human values.
4

There are a lot of definitions for “sustainable” out there. Most are
incomplete. This is what we think “sustainability” means.
Sustainability is a system characteristic which refers to the
system’s capacity to support natural laws and human values.
Natural laws = Ecology
Rule: Don’t break the earth
How we do this:
1. Do not take stuff out of the earth faster than it will go back in.
2. Do not produce stuff (e.g., pollution) faster than it can be
broken down and integrated back into nature.
3. Do not diminish nature’s productivity or diversity or we will
affect nature’s ability to process stuff that we create or use.
5

There are a lot of definitions for “sustainable” out there. Most are
incomplete. This is what we think “sustainability” means.
Sustainability is a system characteristic which refers to the
system’s capacity to support natural laws and human values.
Natural laws = Ecology
Rule: Don’t break the earth
Human values = equity and economy
Equity rule: Seek quality of life for all
Economy rule: Manage resources wisely
Resources = human, natural, manufactured and financial capital
6

There are a lot of definitions for “sustainable” out there. Most are
incomplete. This is what we think “sustainability” means.
Sustainability is a system characteristic which refers to the
system’s capacity to support natural laws and human values.
Sustainability can be:
•Measured
•Judged
•Managed
•Improved
7

There are a lot of definitions for “sustainable” out there. Most are
incomplete. This is what we think “sustainability” means.
Sustainability is a system characteristic which refers to the
system’s capacity to support natural laws and human values.
“Humanity has the ability to make development
sustainable to ensure that it meets the needs of the
present without compromising the ability of future
generations to meet their own needs.”
-UN World Commission on Environment and Development
(WECD) Report (1987) chaired by Gro Harlem Brundtland
(Norway’s prime minister then) on page 24
8

Sustainability does not make much sense unless you also include 4
more items.
• Defining “sustainable” for your project
– Extent: What is the project scope (area, time, location)?
– Expectations: What are the performance expectations?
• Making “sustainability” work
– Experience: Need technical expertise to develop solutions
– Exposure: Education and public awareness
7 total components:
ecology, equity, economic
extent, expectations, experience, exposure
9

We are really just talking about being “more sustainable” than we
were. We are going for “do less bad”. The goal is “do good”.
Good
Bad
Break Even Point
Use > replace
Produce > broken down
Excess = damage
Change nature
humans
10
Use = replace
Produce = broken down
Excess = benefit
Integrated into nature
ants
Example drawn from ideas in McDonough and Braungart’s Cradle to Cradle (2002)
cherry trees
So what does a more sustainable pavement look like?
less paving emissions
env. mgmt. sys.
recycled materials
pedestrian access
local material
art
long-lasting pavement
scenic views
LID stormwater
quality construction
12
less paving emissions
Scenic views
long-lasting pavement
Native vegetation
Natural cut slopes
SWPPP
Minimal footprint
LID stormwater
quality construction
local material
13
We must be careful how we define and measure pavement sustainability.
Using a standard for buildings may not be advisable.
LEED NC v2.2
Total points possible:
Pavement points
possible:
Fraction for
LEED
EB v2
pavements
Greenroads v0.96
69
9
13%
Total points possible:
92
Pavement points
possible:
10
Total points possible:
76
Pavement points
possible:
56
Fraction for pavement
74%
Fraction for
11%
LEED
Neighborhood
pavements
Development
Total points
106
LEED numbers possible:
from Minnesota Asphalt Pavement Alliance
pavement = drainage, recycled material
The Greenroads rating system
Sasobit Warm Mix Asphalt
I-90 near George, WA
23 June 2008
What is it?
Greenroads is a rating system designed to distinguish more sustainable new or
redesigned/rehabilitated roads. It awards points for approved sustainable
choices/practices and can be used to certify projects based on point value.
How does it help?
More sustainable roadways. This means more favorable ecological impact, lower
life cycle costs and better quality of life.
Quiet Pavement
SR 520 Near Bellevue, WA
14 July 2007
Greenroads is a project-oriented system.
It does not deal with planning and it does not deal with operations.
Planning
Design &
Construction
Operation
Greenroads Categories
19
Category
Description
points
Project Requirements
Minimum requirements for a
Greenroad
11
Environment & Water
Stormwater, habitat, vegetation
14
Access & Equity
Modal access, culture, aesthetics,
safety
14
Construction Activities
Construction equipment, quality, use
15
Materials & Resources
Material extraction, processing,
transport
12
Pavement Technology
Pavement design, material use,
function
11
Custom Credits
Write your own credit for approval
10
Total
76
Project Requirements (PR)
Description
NEPA Compliance
Req
Pavement preservation plan
Req
Environmental Maintenance Plan
Req
LID Stormwater Treatment Techniques
Req
Educational Outreach
Req
Construction Quality Control
Req
C&D Waste Management Plan
Req
Life Cycle Cost Analysis
Req
Life Cycle Inventory
Req
Stormwater Pollution Prevention Plan (SWPPP)
Req
Noise Mitigation Plan
Req
Total Requirements
11
Development can substantially change a
watershed’s hydrologic regime.
From the Starting Point: Teaching Entry Level Geoscience
In the NSF National Science Digital Library
Diagram from Massachusetts EEA
Smart Growth/Smart Energy Toolkit
Low impact development (LID) techniques can be used to more
closely match pre-development hydrologic conditions.
•
•
•
•
•
•
22
Bioretention cells
Bioslopes
Catch basin controls
Gutter filters
Infiltration trenches/strips
Permeable pavement
•
•
•
•
•
Pollution prevention
Surface sand filter
Soil amendments
Swales
Vegetation/landscaping
Example PR Requirement
LID Techniques for Stormwater
REQ
The project shall select LID measures that reduce the average
annual post development runoff volume from the project right of
way by at least 50% from conventional design using any of the
following:
Minimizing impact to existing undisturbed soil and vegetation
through avoidance (e.g. lane widths, shoulder widths, slopes)
Permeable hard surfaces instead of conventional impervious
surfaces.
Amended/engineered soils instead of conventional compacted soils
23
Dispersed and infiltration‐based practices (e.g. dispersion,
bioretention) instead of enclosed drainage systems
Materials & Resources (MR)
Description
points
Life Cycle Assessment: Enhanced
2
Native Soil Rehabilitation
1
Pavement Reuse
2
Recycled Content
1-4
Regionally Provided Material
1-2
Energy Efficiency
Total Points Available
1
12
We have done well recycling hot mix asphalt and portland
cement concrete as part of road construction.
Waste in Washington State
18
Asphalt and Concrete Recycled 1999 to 2004
Landfilled
16
Other Diverted Waste
Millions of Tons
14
Diverted HMA and PCC
12
7.91
8.12
10
7.06
8
6.08
6.58
6.12
6.23
6
5.39
4
4.23
3.46
2
0
3.02
0.89
2000
5.28
3.63
3.15
1.12
1.45
1.60
2.00
1.78
HMA/PCC recycling = 30% of diverted waste
2001
2002
25
Graph from Washington State Department of Ecology data
2003
Year
2004
2005
2.30
2006
30% of
diverted
waste
We can do better. We can reduce the amount to landfills,
and increase the amount to high-value surfacings.
Destination of Recovered HMA
Destination of Recovered PCC
Landfill
20%
HMA
27%
Landfill
20%
Base Material
53%
Fill, Rip-Rap
and Other
14%
Base Material
54%
HMA/PCC
12%
26
Data from the USGS
Example MR Credit
Recycled Content
1-4 points
One point: Use recycled content to a minimum of 20% in the
HMA/PCC and 40% of the total material if base course, fill, or
structures are included in the project.
Two points: Use recycled content to a minimum of 30% in the
HMA/PCC and 50% of the total material if base course, fill, or
structures are included in the project.
Three points: Use recycled content to a minimum of 40% in the
HMA/PCC and 60% of the total material if base course, fill, or
structures are included in the project.
27
Four points: Use recycled content to a minimum of 50% in the
HMA/PCC and 70% of the total material if base course, fill, or
structures are included in the project.
Certification Levels
Version 0.96: 76 Total Points
28
23-30 points
31-38 points
39-46 points
47+ points
30-40%
of total
40-50%
of total
50-60%
of total
60+%
of total
Why bother?
Why bother with a rating standard?
• More sustainable roads
• Specific benefits:
–
–
–
–
–
–
30
Defines basic roadway sustainability attributes
Greater participation in roadway sustainability
Better evaluation of tradeoffs and decisions
Provide means for sustainability assessment
Allows innovation because it is end-result oriented
Confer marketable recognition on projects
What makes a roadway more or less sustainable and how do you
translate these qualities into actionable items?
A Convenient List
• Researched and backed
with empirical evidence
• Weighted based on impact
• Each item is directly
actionable on a project level
• Each item referenced to
sustainability components
31
If improving sustainability is an agency/company goal, how do
you assess your performance?
Some examples from LEED:
City of Denver: Greenprint Denver
All City construction projects over 5,000 ft2 and major
rennovations must meet LEED Silver rating level. Goal of
a 10% annual increase in green buildings.
Colorado State University
“The green university.” All new building projcts achieve a
LEED Gold rating. Received an “A” rating in buildings
from the College Sustainability Report Card.
State of Colorado
All State funded projects (over 25% state funds) shall be
built to the highest green building standard such as
LEED. Initial construction costs must be recovered in 15
years or less.
33
Why should a contractor care?
Because there is money to be made.
One example…
34
From the Turner Construction website:
“Turner has extensive experience across
a wide variety of sustainable
construction projects, enabling us to
create a detailed databank of costeffective Green materials, processes and
suppliers to assist our clients. From our
experience, the costs associated with
these projects can be contained to a
level comparable to traditionally
constructed buildings.”
•80+ LEED certified projects
•120+ additional LEED registered projects
•300+ projects with Green elements
•600+ LEED Accredited Professionals
We need to be on the map.
Construction Market
35
Source: ENR (24 Sep 2007)
The Mainstreaming of Green Building (Tulacz)
Design Market
Source: ENR (18 May 2008)
No Longer a Fad, Green Hits Mainstream (Tulacz and Traynor)
Greenroads effort right now…
(14 March 2016)
• Who is developing Greenroads?
– University of Washington and CH2M HILL
• Who is funding Greenroads so far?
– TransNow (DOT Region 10 University Transportation Center)
– State Pavement Technology Consortium (WA, CA, MN, TX)
– Federal Lands Highway Division (FLHD)
• What is the status right now?
– Version 0.96 now
– Online: www.greenroads.us
• When can it be used?
– We want comments and pilot projects NOW
– Let us know via the website (www.greenroads.us)
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Sustainability is the next great game in transportation.
The game becomes serious when you keep score.
Greenroads keeps score.