Green Streets & Sidewalks

Trees and landscape features located within the public right-of-way and adjacent to roadways in urban environments are often perceived by transportation officials as a safety risk. However, evidence from national and local studies reveal that the inclusion of trees and other streetscape features actually reduces crashes and injuries on urban roadways.



Ultimately, conservation is about empowering citizens to improve the communities where they live and work. The Alliance for Community Trees is the only national organization working to improve the urban forests where 80% of Americans live- our cities, towns, and villages. ACT’s national office assembles coalitions that drive broad environmental success for our more than 180 organizations in 41 states in the pursuit of Clean Air, Green Streets, and Healthy Neighborhoods.
Urban forestry is simply about trees in places where people live.
Trees help to calm traffic. Research done in Orlando and Delaware has shown that motorists benefit from vertical features such as trees and buildings to gauge their speed. Other studies that identify commuting as one of the most stressful experiences of urban life showed that stress response decreases and frustration tolerance increases with views of nature. Three-fourths of Americans believe that being smarter about development and improving public transportation are better long-term solutions for reducing traffic congestion than building new roads.
Conventional approaches to transportation engineering discourage the use of trees and other roadside features as being fixed-object hazards. Green infrastructure may be limited or prohibited by public works or transportation professionals due to concerns. But there are many community benefits that result from having roadside landscapes. They include:
Safer Streets
Transportation safety is a highly contentious issue in the design of cities and communities. While urban designers, architects, and planners often encourage the use of aesthetic streetscape treatments to enhance the livability of urban streets, conventional transportation safety practice regards roadside features such as street trees as fixed-object hazards and strongly discourages their use. Yet studies show that trees actually make urban streets safer, not deadlier. Concerns about their safety effects do not appear to be founded on empirical observations of crash performance, but instead on street design philosophy that discounts the relationship between driver behavior and safety.
Less Maintenance Costs
All other factors equal, the condition of pavement on tree-shaded streets is better than on unshaded streets. In fact, shaded roads require significantly less maintenance and can save up to 60% of repaving costs over 30 years. After more than 100 years of road and highway building, the United States is now crisscrossed by nearly four million miles of roadways. Add in all the parking lots, private roads, driveways, and road shoulders, and the total amount of paved land comes to approximately one percent of the total area of the contiguous United States. The cost of maintaining asphalt can be lowered through urban tree planting.
Reduce Traffic Congestion
Transportation systems have traditionally been designed for traffic mobility and driver safety. However, research suggests that urban road projects could safely accommodate more trees than are currently allowed in transportation building codes. Context Sensitive Design is a new approach in transportation planning that recognizes community values, and is showing that more roadside vegetation along transportation corridors may actually equal less traffic congestion.
Cleaner air
Studies show that trees and shrubs have the greatest impact at minimizing air pollution including the effects of ozone, followed by particulate matter, nitrogen dioxide, sulfur dioxide, and carbon monoxide, which are harmful automotive outputs.
Highway Beautification
Around the country, urban forestry organizations are helping their communities envision and design green streetscape improvements that enhance transportation corridors. For example, since 1996 Trees Forever has provided resources and assistance with planning, landscape design, and funding opportunities for planting native grasses, wildflowers, shrubs, and trees. The program is called Iowa’s Living Roadways. Funded by the Iowa Department of Transportation using Federal Highway Administration monies, the program beautifies and enhances roadsides and community entryways. An example of how this program can be funded and implemented on the municipal level is modeled by Baton Rouge Living Roadways.
Mitigation of highway noise
City dwellers need green in their lives, especially if they live near a highway or along a mass transit corridor. Not only are trees prettier to look at than asphalt, speeding cars, and industrial areas, but also trees reduce noise pollution by acting as buffers. Trees absorb the cacophony of urban life, where every highway should be turned into a greenway.
At this moment, the nation wants action to secure real solutions to urban planning, action that goes beyond buzzwords such as green and sustainable. Healthy urban forests are key to helping our growing cities and towns to balance transportation mobility, accessibility needs, public welfare, and community livability.
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Green Roofs & Buildings
The Alliance for Community Trees is a 501(c)3 tax exempt organization (EIN # 68-0319301), and also participates in the Combined Federal Campaign (CFC # 12402). To discuss planned giving opportunities, call us at 301-277-0040.


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