Attachment to Bts Letter s1

AASHTO STANDING COMMITTEE ON RESEARCH

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

NCHRP Problem Statement Outline

I. PROBLEM NUMBER

To be assigned by NCHRP staff.

II. PROBLEM TITLE

Evaluate the Potential Benefits of Roadside Trees to Reduce Greenhouse Gas Concentrations and Improve Water Quality

III. RESEARCH PROBLEM STATEMENT

Air pollution reduction and water quality protection are critical public health and ecologic challenges facing Departments of Transportation (DOTs) throughout the country. DOTs are obligated to meet environmental requirements mandated by legislation such as the Federal Clean Air and Water Acts and to develop flexible, long-term and cost effective strategies to meet these regulatory requirements. To expand the toolbox of strategies there is a need to understand the environmental and economic value of the air pollution removal capacity and the stormwater treatment benefits of existing and new trees in the state right-of-way. Trees are proven mitigation measures that sequester carbon, shade impervious surfaces, function as non-structural stormwater management facilities, and improve erosion control and groundwater recharge. Many DOTs are considering the implementation of extensive tree planting programs as a response to climate change without a complete understanding of best practice strategies.

IV. LITERATURE SEARCH SUMMARY

American Forests. ‘Trees and Ecosystem Services’, http://www.americanforests.org/resources/urbanforests/naturevalue.php

Caltrans Division of Environmental Analysis, 2003. ‘Roadside Vegetated Treatment Study’, http://www.dot.ca.gov/hq/env/stormwater/pdf/CTSW-RT-03-028.pdf

McPherson, E. Gregory; Simpson, James R. (1999) ‘Carbon Dioxide Reduction Through Urban Forestry: Guidelines for Professional and Volunteer Tree Planters’, http://www.fs.fed.us/psw/publications/documents/psw_gtr171/

West Coast Regional Carbon Sequestration Partnership, 2006. ‘Terrestrial Storage’, http://www.westcarb.org/terre_storage.htm

V. RESEARCH OBJECTIVE

Using tools such as GIS and urban forestry software, a consultant would synthesize existing data and conduct statistical analyses to determine the economic and environmental value of air pollution removal and stormwater treatment benefits provided by trees in the right-of-way. Existing research on this issue has concentrated on the value of extremely large tracts of forest lands to provide ecologic benefits. Information is needed on the potential benefits of liner forests adjacent to the highway environment. Many DOTs have implemented vegetative roadside storm water treatments using grasses, low-growing shrubs and groundcovers. There is a need to understand how trees fit into the equation. Research will identify environmental benefits provided by trees, identify agencies (state, national and international) that have successfully developed similar programs, and draft strategic plans and business plan models to implement recommended guidance.

VI. ESTIMATE OF PROBLEM FUNDING AND RESEARCH PERIOD

It is estimated that the proposed research will require $450,000 and 36 months to accomplish, including three months for preparation of a draft final report.

VII. URGENCY, PAYOFF POTENTIAL, AND IMPLEMENTATION

Quantifying the air pollution removal and stormwater treatment services provided by trees will assist DOTs in developing cost effective practices to meet Federal clean air and water regulations and making better land use decisions to assist in the reduction of global climate change.

VIII. PERSON(S) DEVELOPING THE PROBLEM

Keith Robinson, ASLA

Principal Landscape Architect

State of California Department of Transportation

Landscape Architecture Program, Mail Station 28

1120 N Street

Sacramento, CA 95814

Phone: 916-654-6200

Email:

Barbara Petrarca, ASLA

(Chair, TRB AFB40)

Supervising Landscape Architect

Rhode Island DOT

2 Capitol Hill

Providence, RI 02903

Phone: 401-222-2023 x 4090

Email:

IX. PROBLEM MONITOR

The problem will be monitored by a representative of TRB Committee AFB40 and a representative of Caltrans, inclusive of the individuals mentioned above under Section VII.

X. DATE AND SUBMITTED BY

This research problem statement is hereby submitted on 9/15/08 by the Rhode Island Department of Transportation.

Please submit completed problem statement to the following e-mail address:

Questions on the process can be directed to the same address or .

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