How Much Green Infrastructure?

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 [email protected] & [email protected]

Resilient Cities 2012-Session H2-Bonn, Germany

May 12-15, 2012

How Much Green Infrastructure? Example of the Boston Region