How Much Green Infrastructure? Example of the Boston Region

Yaser Abunnasr Assistant Professor, American University of Beirut

PhD Candidate in Regional planning, University of Massachusetts Amherst

Resilient Cities 2012-Session H2-Bonn, Germany

May 12-15, 2012

• Green Infrastructure (GI) as a spatial planning tool • Provides ecosystem services and benefits,

network of spatial elements, multi-functional, multiple scales, multi-disciplinary, natural and engineered natural systems .

• Complementarity • GI Characteristics fulfill adaptation needs • Rethink infrastructural solutions • No-regrets policy

• GI as an infrastructural system • A ‘living system’ infrastructure • Surface infrastructure • Multiple benefits versus single benefit • No direct monitory valuation

Green Infrastructure

Neighborhood

Urban

Street

Region

Infrastructure System

Green Infrastructure and adaptation

• Explicit Adaptation Focus of GI

• Risk Exposure: Potential reduction

• Inherent vulnerability: A ‘living infrastructure’

• Current and future conditions: Operation & function

• Targeted planning: specific ecosystem benefits to respond to context specific CC impacts

• Increase benefits: Increase surface areas & intensify GI

• Regional network strategy & local implementation policies

• Space: Potential conflict with mitigation

Measure why and what?

• Why?

• Infrastructure: understand capacities • An effective adaptation planning tool (local, urban &

regional scales)

• Limitations and opportunities • How much services? • Alternative and parallel policies

• Set strategy: where to increase and intensify GI • Scenarios of ecosystem services delivery: current and

future conditions • Provides priority of GI planning based on contextual

considerations • Cross-jurisdictional coordination

Measure why and what? Ecosystem Benefits

•Run-off reduction • Improve water

quality •Reduces flooding •Reduce energy use •Reduces CO2

•Reduces UHI •Urban agriculture • Improves habitat

• Environment Engineering • Ecologists • Earth

Scientists •Biologists

Quantification Method

IMPPERVIOUS AREAS

VEGETATED/ PERVIOUS

AREAS

Common Unit of Measure

Primary Indicator of adaptive capacity –GI Application

• Environmental Engineering • Ecologists • Earth Scientists •Biologists

Urban Context

CONTEXTUAL CC

IMPACTS

Reduce & control if /when Possible

Transform

PRESERVE &

INCREASE AREA

INTENSIFY GI SPATIAL

TYPOLOGIES

•Street Trees •Green Roofs •Green Facades •Private Yards •Urban Forests •Parks •Habitat

Connectivity

CC Impacts

• Projected Climate Impacts •Temperature + 4 to 7⁰C •Sea level rise + 25 to 60cm •Precipitation + by 20%-30% •Snow Less snow days •Events More Sever/flooding

Massachusetts / USA

Sea level Impact : change in 100 yr flood (Union of concerned Scientists, 2008)

Hardiness Migration (Union of concerned Scientists, 2008)

Mapping Pervious & Impervious Surfaces

Impervious Surfaces

Pervious Surfaces

LOC

AL

SCA

LE

REG

ION

AL

SCA

LE

GI Benefits: Where people are

Population distribution impervious surfaces Potential increase of GI surface area

Town Scale

Concluding Remarks

• So How much GI do we plan for? • Difficult to put a generalized figure number: urban region

context specific • Aim for maximum possible: current and future conditions • Variable GI policies and combinations with other measures

(urban matrix context: urban center, sub-urban, peri-urban)

• Variable GI Stand alone solutions or with other policies • Depends on community and regional climatic projections • Dependent on climatic and geographic conditions • Implement (locally) but coordinate (regionally)

• Constraints • Jurisdictional and political barriers • Socio-political context – will of people and politicians

Yaser Abunnasr Assistant Professor, American University of Beirut

PhD Candidate in Regional planning, University of Massachusetts Amherst yabunnas@gmail.com & ya20@aub.edu.lb

Resilient Cities 2012-Session H2-Bonn, Germany

May 12-15, 2012

How Much Green Infrastructure? Example of the Boston Region