Calculating the Carbon Footprint of Development

ProjectsLynn Richards

US EPA Smart Growth ProgramJune 13th 2008

CNU 17 - Experiencing the New Urbanism

What are you counting?

• Construction • Building Energy Use• Transportation Related Emissions

– Residential– Office – Retail, Entertainment & Services– Manufacturing, Distribution Facilities,

etc.

Difference in CO2 Emissions - High vs. Low Density Residential

Development

0.0

1.0

2.0

3.0

4.0

5.0

6.0

Construction Building Operations Transportation

Met

ric

Ton

s of

CO

2

Low Density

High Density

Source – Norman et al (2006) “Comparing High & Low Residential Density”

Where do the transportation reductions come from?

• Where and How you build– Easy access to retail, services,

entertainment = more walking and biking for non-work trips

– Safe routes to school = fewer drop-off trips – Proximity to transit = less commuting by

car– Regional Accessibility = shorter car trips

• E.g. driving 1 mile vs. 3 miles to the grocery store

The Five D’s

• Density• Diversity of Land Use Types• Neighborhood Design• Distance to Transit• Access to Regional Destinations

Neighborhood Scale D s

4 Units per Acre

(1) Residential Density

11 Units per Acre

Source: Campoli (2007) Visualizing Density, Lincoln Institute of Land Policy

(2) Diversity of Land Use

Source: EPA White Paper: The Placemaking Premium. Victor Dover. 2007. Illustrations courtesy of Dover Kohl and Partners.

(3) Neighborhood Design - Network Connectivity

(3) Neighborhood Design, con’tTransit & Pedestrian Friendly

Design

Regional Scale D s

(4) Distance to TransitWhat Kind of Transit Are You

Accessing?Philadelphia

Chicago

Boston

Atlanta

LA

Wash. DC

How Close are You to the Station?

Source – Cervero (2006) Office Development, Rail Transit, and Commuting Choices

(5) Proximity to Destinations

M

M

M

M

M

Lower Density ZoningLower Density Zoning

Arlington, VA– (4) Distance to Transit and (5) Regional Destinations

Doubling of Each D Reduces VMT by…

-16%

-14%

-12%

-10%

-8%

-6%

-4%

-2%

0%

Densit

y

Diversi

ty

Desig

n

Distan

ce to

Tran

sit

Region

al Des

tinati

ons

Source – Ewing (2009) Travel and the Built Environment - A Meta-Analysis

Different Modeling Approaches

• Simple adjustment factors (aka back of the envelope)

• Analysis using baseline data from census or regional transportation models

• Sketch planning models (INDEX, Places, etc)

• Site-level analysis combined with a regional transportation model run (Atlanta Station INDEX + ARC Model--standard regional travel model)

Mixed Use Trip Generation Tool

• National Study of Mixed Use Areas – 239 mixed use developments– In six different regions– Over 30,000 trip records

• Resulting Tool More Accurately Accounts for…– Trips that stay on site– Trips that leave, but use transit– Trips that leave, but are on-foot

Example: Traditional Residential and Office Project

• 100 Acres• 200 Single

Family Homes• 40,000 sq ft

Supermarket• 5,000 sq ft Fast

Food Restaurant

• 200,000 sq ft office building

10,000 Daily Trips

Traditional Residential, Office, Retail Project

Smaller Grocery Store and Different Retail / Residential

Configuration (apply density, diversity, and

design)• 100 Acres• 100 Single Family Homes• 100 Multi Family Homes• 30,000 sq ft Supermarket• 5,000 sq ft Sit Down

Restaurant• 10,000 sq ft Health Club• 200,000 sq ft office

building

8,000 Daily Trips

Smaller Grocery Store and Different Retail

Better Local and Regional Accessibility

(apply distance to transit and regional destination)• Same land use

configuration• Double

intersection density on site

• 500,000 jobs within a 30 min transit trip

• 50,000 jobs within 1 mile

M

M

M

M

M

6,500 Daily Trips

Better Local and Regional Accessibility

An Example: Tysons Corner / Dulles Metro Extension

Existing Conditions…

Source: PB PlaceMaking “Tysons Corner: Path to the 21st Century: Draft Summary of Findings” Prepared for Tysons Land Use Task Force 27 February 2008

Planned Future…

Tysons: What’s the GHG Impact?

• Households built somewhere else in Fairfax County– 0.5 Million Metric Tons CO2 per year

• Increased transit share for work trips – 1.6 Million Metric Tons CO2 per year

• Retail and other trips staying “on-site”– 0.2 Million Metric Tons CO2 per year

• Total = 2.3 Million Metric Tons CO2 per year– More than double the reductions from Fairfax

County‘s current Climate Action Plan– About ¼ of the emissions from a coal fired power

plant (annual)

Take Away Points…

• Where and how you grow can reduce carbon footprint

• Good development can be a strategy to help communities meet their carbon reduction goals

• Some tools exist, more are needed– its an emerging area

Thank You Lynn Richards,

EPA’s Smart Growth Program

202-566-2858

Richards.Lynn@epa.gov

But who you *really* want:

John Thomas, resident transportation geek

202 566 1285

Thomas.john@epa.gov