The Melbourne Urban Forest Accord Group’s approach to

Urban Ecological Management

Melbourne Urban Forest Accord Group

City of Melbourne City of Port Phillip Moonee Valley City Council

HOW DID IT ALL BEGIN?

Policy Gaps - 2009Targets: • Saving Water – 25%

water saving by 2020

Achieve this by:• Reduce potable water in

parks• Irrigation efficiencies• Drought tolerant

species

Is reducing water the best outcome for our Parks and Trees?

Drought and water restrictions vsparks and trees

Alexander Park – Feb 2004Alexander Park – Feb 2010

Kings Domain & surrounds852 trees assessed

ideal

CoM Urban Forest Strategy

Trees + Water = Healthy Environments

Further gaps

•Trees seen purely as a risk in causing damage during extreme weather events

•No value given to their ability to “cool” the local environ - adaptation

•No value given to carbon sequestration

Further gaps

• At present, we can only value our trees using The Burnley Amenity Value Formula = cost of replacing the tree

• Currently very small fines/permit costs for removing urban trees

• No economic incentive for tree retention

Unable to truly quantify the environmental benefits of urban trees

How can we value Urban Trees?

• Funding bid submitted to the Victorian Sustainability Accord

• Need recognised at State Government level

• Funding of $70,000 awarded• MUFAG thus initiated!

Working Group

University of MelbourneMonash University

RMITMelbourne Water

Department of HealthCity West Water

Arboriculture Australia

DEVELOPMENT OF A PROJECT BRIEF

What are the benefits of urban trees?

Environmental

Social

Economic

Chicago Urban Forest Project 1991Chicago trees removed 6,154 tons of air pollutants valued at US$9.2m

Total Co2 sequestration = 155,000 tons per year

Increasing tree cover by 10% (3 trees per building) could

reduce total heating and cooling energy use by 5-10%

Cost benefit ratio of 2.83

Existing Valuations in Melbourne

Valuing Urban Trees

Parameter Measurements

CoM Amenity Value Formula I Tree Streets/Eco This project

Replacement value from nursery Energy conservation Greenhouse gas

Species FactorAir quality improvement Water use

Aesthetics Co2 reduction Air Quality

LocalityStormwater amelioration Climate adaptation

Tree Condition/HealthProperty value increase

Infrastructure and horticultural implications

I Tree Streets

• Free to all users• Must have good base data on existing urban forest i.e.

species, health of canopy, DBH, cost of maintenance programs, demographic data for selected area, resident populations, linear miles of streets, local electricity costs

• Doesn’t value social benefits such as community wellbeing and health

• Biggest issue: customised for USA (species, hardiness zones etc etc)

• Tom Fairman from Melbourne University: pilot project to overlay usefulness of I Tree Streets into Australian context

I Tree

• Model needs to be redesigned to include Australian climatic data and tree species

• Results valued urban forests in Carlton and NW Melbourne at roughly $1.06m. Biggest benefits in aesthetics and energy savings

• Need to look at return samples to understand the change in value of the trees over time. This will determine age mix of trees that provide greatest benefit

• Also need to look at economics of the urban forest: how costs vary under different management regimes over time and for different trees to determine exact cost of running an urban forest. May be that councils may lose money on some trees!

• BUT, there are international users

CITYgreen

• Uses GIS software to quantify benefits and map urban canopy

• Fee charged for software• Similar parameters: reducing stormwater run-off,

mitigating air pollution, energy savings, tree growth, water quality

• Developed by American Forests, a not for profit conservation group

• Coupled with urban ecosystem analysis to map urban canopies and their dollar values

• Not recommended for international use due to US specifications

UFORE Program

• Urban Forest Effects Model

• Calculates structure, environmental effects and values of urban forests

• Funded and developed by USDA Forest Service

• 4 types of data needed: field data, tree cover, meteorological data and pollution concentration data

• It then quantifies:– forest structure (species, density, health, biomass)– Volatile organic compounds ( urban forest emissions)– Carbon storage and sequestration– Dry deposition of air pollution (ability of urban forest to remove pollution)– Effects of trees on building energy use– Compensatory value of urban forest

IS NOW i-tree ECO

Australian attempts to value urban forest

Brisbane City Council: desktop study mapping the urban canopy using GIS and satellite imagery coupled with existing on-ground data. Consultant based report in 2001. No field studies.

• Suburbs averaged 27% canopy cover

• Modelled valuation on CITYgreen’s approach

Results:

• Urban forest absorbing co2 equivalent to 130,000 cars annually

• Cooling surfaces in October by 5 degrees Celsius

• Potential for tree shading on east and west sides of buildings to provide energy savings of up to 50%

• Value of homes in leafy streets were 30% higher than non-leafy streets in same suburb

Australian attempts to value urban forest

• Canberra: Set up an Urban Forest Renewal Program to account for mature trees reaching end of their lives. ANU study in 2005 on the urban forest valued it at $15m, saved up to $3.9m in energy costs, provided $7.9m in air pollution mitigation and $3.5m in stormwater mitigation and reduced wind speed by up to 50%

i-tree Eco

• MUFAG developed close collaboration with USDF and Davey Trees, Dave Nowak and Scott Maco

• Agreement to create i-tree Eco International, using Melbourne as a pilot program

• If successful, i-tree Eco will be rolled out for other international users

Recalibration

Consultant = Enspec

Requirements:

• List of Australian tree species

• Meteorological and Climate Data

MANY QUESTIONS……..Dave Nowak

Is Australia ready to use i-tree?• Not yet, but its worth considering what

data needs to be collected by council arborists:- Species name- Location of each tree, land use, distance and direction to nearest buildings, sunlight source, street tree or park tree.- Size of each tree, trunk diameter, trunk height, crown width, Health of each tree, age, canopy missing, crown dieback.

Some councils have already begun data collectionFirst version due for completion July 2011

How will this project help us?

Council: • Development of our Urban Forest Strategy• Investment planning: $1 invested in street trees

returns $x

State Government: • Robust evidence for inclusion of trees in

planning• Understand the economic consequences of

water restrictions and provide cost benefit analysis for WSUD

Community• Raise awareness of urban tree benefits• Encourage private landholders to include real

tree values in their development analysis