A Policy Evaluation of Planting Street Trees Benefit-Cost Analysis

advertisement
A Policy Evaluation of Planting Street Trees
in Morgantown, West Virginia: A Spatial and
Benefit-Cost Analysis
GIS Conference and Workshop 2004
Vishakha Maskey
Graduate Research Assistant
[email protected]
Division of Resource Management
Background Information:
• Urban Forests
– Street trees, trees on the private property, and
parks
• Street Trees
– Trees that are publicly owned
– Are within 6 feet of the road
Overview of Tree Benefits:
Ecological and Health Benefits through:
• Air pollution removal
• Carbon reduction, Oxygen production
• Biodiversity maintenance
• Stormwater management
Benefits cont.
Social and Economic Benefits through:
• Increase in aesthetic value (property prices)
• Replacement value
• Psychological value
•
Lower crime rate
• Traffic safety
Overview of Tree Costs:
Social/Economic Cost
Ecological cost
• Sidewalk and property
damage
• Hydrocarbon production
• Maintenance cost
• Water consumption
• Planting and replacement
cost
• Displacement of native
species
• Pollen allergies
Problem Statement:
• Increased development and population pressure
• Decreasing tree cover
• Lack of planting and proper maintenance initiative
due to unobserved benefits in the market
• Investment decisions dependent upon costs of
implementation
Why Morgantown, West Virginia?
• Decreasing aesthetics of the city
• Air quality problems
• Initiatives from different governmental and nongovernmental sectors
• Many plantable spaces that need cost- effective
decision on plantings
Objective of the Research:
• Develop an infrastructure for planting street trees;
• Facilitate decisions on future plantings with
reliable monetary information on costs and
benefits;
• Generate a valid argument on planting decision.
Conceptual Framework:
Tree number
Costs
-Infrastructure
- Planting
-Maintenance
-Removal
Benefits
Energy savings
Pollution control
Runoff Control
Carbon Dioxide
Water Conserved
Benefit-Cost Analysis
Net Benefits
B/C Ratios
IRR
Research Method Application:
• Spatial Analysis to develop infrastructure
•
Benefit- Cost analysis to facilitate policy decisions
Spatial Analysis:
Categorized all streets in Morgantown into suitability
Index with respect to soil type, slope and land
cover:
– Most suitable
– Moderately suitable
– Unsuitable
Benefit-Cost Analysis
• Methodology: NPV=
40
 (Bt-Ct)/(1+i)^t
i
t0
– Where NPV = Net Present Value, Years (t) = 0 …….40
– Discount Rate (i) = 7 %,
– B = Total Benefit
– C = Total Cost
Benefit and Costs Per Year:
• Air Quality Benefits = $16 per tree
• Stormwater runoff reduction = $6.76
per tree
• Carbon dioxide reduction = $5 per tree
• Aesthetic Benefit = $17 per tree
• Energy Savings =$10 per tree
• These estimates are lower
bound of previous researches
done my McPherson in
California.
• Fixed costs
– Planting Costs =$500 per
tree
– Sidewalk and Curb Cost
=$1,127 which includes
equipment, material and
labor cost
• Variable cost
– Maintenance Costs = $9.61
per tree
• Cost estimates are from
Mr. Bill Rumble (City of
Morgantown) and Dr.
Cummings (Morgantown
Tree Board)
Estimates:
• The net benefit per tree = $ 54.76
• Benefit-cost ratio = 2.25:1
• Net Present Value (NPV) of $20,491.30
• IRR (Internal Rate of Return) of 12%.
Conclusions:
• The accounting of benefit and costs of planting 20
new trees seems feasible;
• Positive net benefit should serve as argument for
funding;
• The costs and benefits are dynamic and projections
may not be accurate.
Policy Recommendation:
• Better City ordinance
• Subsidies or payment for maintenance and
replacement
• Incorporating Citizen forester program
– Training and information
• More reliable benefit quantification required using
computer based programs such as STRATUM,
which quantifies benefits of street trees.
Thank you for your attention!
Download