AASHTO STANDING COMMITTEE ON RESEARCH

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

NCHRP Problem Statement Outline

I. PROBLEM NUMBER

To be determined by NCHRP staff.

II. PROBLEM TITLE

Green Transportation Infrastructure: Low Impact Design Storm Water Strategies to Mitigate the Impacts of Climate Change

III. RESEARCH PROBLEM STATEMENT

The impacts of climate change challenge Departments of Transportation (DOTs) to develop design strategies to protect transportation infrastructure investments. Changing weather patterns, particularly less frequent but higher intensity rain events, threaten to overwhelm the capacity of existing roadway systems and challenge the validity of standard roadside design treatments. Retrofitting and building new traditional structural storm water infrastructure is a costly proposition. New and emerging strategies in green storm water infrastructure involving vegetative and soil solutions have the potential to enhance or replace existing drainage facilities to improve storm water infiltration and improve exiting infrastructure capacity.

Green Infrastructure strategies, commonly known as low impact design (LID) may be highly efficient, environmentally sound, and have low life-cycle costs. Functioning as non-structural storm water management facilities, LID strategies intercept and slow storm water flows, reducing the volume of water that must be conveyed and stored, and ultimately reduce the cost of constructing and maintaining traditional storm water infrastructure. To expand the DOTs toolbox of roadside design strategies that address climate change, there is a need to understand how to best implement vegetation and soil storm water infrastructure treatments in the transportation environment.

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

Environmental Protection Agency, 2007. Managing Wet Weather with Green Infrastructure Action Survey.

Humphrey, Nancy P., 2008. Potential Impacts of Climate Change on U.S. Transportation

Meyer, Michael D., 2008. Design Standards for U.S. Transportation Infrastructure: The Implications of Climate Change.

Xiao, Q., E.G. McPherson, S.L. Ustin and M.E. Grismer. 2000. A New Approach to Modeling Tree Rainfall Interception. Journal of Geophysical Research 105(D23) :29,173-29,188

This proposal is intended to fill the research gap in LID best practices in the highway environment by providing a synthesis of research literature and identifying innovative practices for DOTs to use.

V. RESEARCH OBJECTIVE

The objective of the research is to develop best practices of LID strategies to reduce the impact of high intensity rain events caused by climate change thorough review and analysis of research literature. In addition to synthesizing the research findings, the goal is to identify innovative practices and strategies to address changing precipitation patterns and roadside erosion potential. The expected final product is a literature review final report and recommended best practices. The final report will include recommendations strategies to implement innovative practices in the transportation environment.

VI. ESTIMATE OF PROBLEM FUNDING AND RESEARCH PERIOD

Recommended Funding:

It is estimated that the proposed research will require $300,000.

Research Period:

It is estimated that the proposed research will require 27 months to accomplish, including three months for preparation of a draft final report.

VII. URGENCY, PAYOFF POTENTIAL, AND IMPLEMENTATION

Climate extremes will stress transportation storm water infrastructure with the potential to cause catastrophic failures to the transportation system. Understanding alternative storm water design strategies will assist DOTs in developing a comprehensive approach to evaluating, designing and maintaining the roadside environment to protect the transportation investment.

Recommendations from the literature review and analysis will assist DOTs in developing cost effective best management practices that can address and accommodate increased storm water volume due to 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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