Green Streets Oregon

A multi-disciplinary team was selected to develop alternative street design guidelines that minimized the impact of road systems to the environment. Project objectives addressed conflicts between good transportation design, planned urbanization in urban reserves, and the need to protect streams and wildlife corridors in urban reserves. The effort included development of new street connectivity provisions for adoption into regional and local plans that address tradeoffs between stream protection and an efficient multi-modal transportation system.

A green street can be defined as a street designed to:

• Integrate a system of stormwater management within its right of way
• Reduce the amount of water that is piped directly to streams and rivers
• Be a visible component of a system of “green infrastructure” that is incorporated into the aesthetics of the community
• Make the best use of the street tree canopy for stormwater interception as well as temperature mitigation and air quality improvement
• Ensure the street has the least impact on its surroundings, particularly at locations where it crosses a stream or other sensitive area

The design and construction of green streets is one component of a larger watershed approach to improving the region's water quality, and requires a more broad-based alliance for its planning, funding, maintenance and monitoring

The purpose of the "Green Streets" project is to provide tools and guidelines for achieving this mission within the public right-of-way. These tools will promote the following:

• Viewing the public right-of-way and urban run-off from streets as an extension of the natural stream system;
• A street system whose design mimics the natural hydrology of the area and protects streams from urban storm water run-off;
• Minimizing the negative effects of stream crossings;
• A level of neighborhood and street connectivity that promotes walking, bicycling and transit use, and reduces the demand to further expand major streets;
• Storm water treatment and retention facilities that are integrated into the open space resources of a community; and
• Alternative street designs that are cost-effective.

The Green Streets Handbook, produced as a tool for implementation, provides acceptable design guidelines for situations where major street corridors or connectivity requirements conflict with protecting or restoring streams and/or wildlife corridors.