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close windowCase Study No. 32
Portland, ORÂ
Information provided by George M. Hudson, Landscape Architect, former City of Portland Park Planner, Trail Program Manager.
Safe intersection crossings were needed for a trail that intersects with several roads.
A typical major intersection treatment.
A typical minor intersection treatment.
A bicycle-activated Signal Loop Detector.
A pedestrian-activated signal button in a refuge island.
The Springwater Corridor is a 16.8 mi former rail corridor converted into a recreational non-motorized commuter trail in 1996. Located in southeast Portland, Oregon, the corridor extends eastward to the City of Gresham and links to the small, unincorporated community of Boring. The route it travels features a variety of landscapes and includes industrial, commercial, and residential areas.
Master planning for the project began in 1992 after the Intermodal Surface Transportation Efficiency Act (ISTEA) was passed in 1991. Based upon 1990 census data, surrounding population densities, and a recent City of Portland Parks & Recreation Department park user survey, use levels were projected for the corridor at an annual rate of approximately 400,000 people per year. Anticipated uses included bicycling (56%), walking (36%), jogging (9%), and equestrian (3%). The trail would be multiuse, and include a 3.7 m (12 ft) wide paved surface with 0.6 m (2 ft) wide soft shoulders and a separated equestrian trail wherever feasible.
The Springwater Corridor is unusual because it does not fall into a road right-of-way. This eliminates the conflicts between trail users and automobiles found on most roadway bicycle lanes. The corridor, however, does intersect with several roads. Addressing these intersections was essential to ensure trail user safety and to minimize automobile and trail user conflicts. With growth in the Portland metropolitan region projected to increase automobile traffic, the situation would only become more aggravated.
The intersections were broken into three categories—major intersections, minor intersections, and private driveway crossings—based upon type of use, roadway width, traffic gaps available for pedestrian crossings, automobile volume, and automobile speed.
Minimal improvements at all intersections included:
Due to high automobile traffic volume resulting in a high degree of crossing difficulty, six major intersections were identified along the Springwater Corridor at Johnson Creek Boulevard—SE 45th, 82nd Avenue, 92nd Avenue, Foster Road, 122nd Avenue, and Eastman Parkway in the City of Gresham. Eighty-second Avenue is a State-owned route. The Oregon Department of Transportation required meeting traffic signal warrants to justify the installation of a signal at the trail and roadway intersection at 82nd Avenue. User counts of a minimum of 100 trail users per hour for any 4 hours within a day had to be met. Trail user counts were carried out on an existing improved segment of the trail within the City of Gresham. Warrants were met and the state approved a signal installation.
Improvements installed at major intersections included pedestrian- and bicyclist-activated signals, median refuge islands with a signal-activating button, signage forewarning both the trail users and motorists of the approaching intersection, and crosswalk striping. In addition, curb extensions and a realignment of the trail to minimize crossing distance were incorporated into the intersection design.
Defined as crossings at public roadways that present a low to moderate degree of difficulty in crossing, 28 minor intersections along the Springwater Corridor were identified due to their low traffic volume and minimal width. Minor intersections were treated similar to major intersections with the deletion of the pedestrian-activated signals. A few intersections deemed challenging to cross received overhead flashing yellow pedestrian warning signs.
Private driveways were defined as vehicle crossings providing access to private property and businesses adjacent to the trail, which serve a private citizen or a group of citizens. Improvements installed to prevent a private property from being land locked included fixed and removal bollards, stop signs for automobile traffic, a raised trail surface with warning striping to act as a speed table for motorists, and placement of locally found basalt boulders to restrict vehicle access to the corridor. The City decided to restrict future additions of private driveway crossings and to combine private driveway crossings wherever feasible.
The installation of trail improvements was completed in 1996. Since that time, there has been only one reported accident at an intersection resulting in an injury. This single accident was between an equestrian and a car. The horse became startled, bucked off its rider, and bolted into an intersection. The accident clearly was not due to a faulty design, but perhaps an inexperienced rider.
Based on the interim user counts to establish warrants at the 82nd Avenue intersection, use levels of the Springwater Corridor are now exceeding the use level projections made during the master planning effort. Plans currently underway to link the Springwater Corridor from southeast Portland to downtown Portland with a Class I bikeway are anticipated to be in place by early 2003. User projections at that time are expected to exceed one million users per year.
In conclusion, the intersection designs along the Springwater Corridor adequately addressed public safety and reduced potential conflicts between trail users and automobiles.
George Hudson, Senior Associate
Alta Transportation Consulting
144 NE 28th
Portland, OR 97232
Phone: (503) 230-9862
Fax: (503) 230-9864
E-mail: georgehudson@altaplanning.com