Twenty-five residents and business owners along the Tangerine Road Corridor stretching from I-10 in Marana to La Cañada Drive in Oro Valley took a first-hand look at proposed access points to the roadway during a public meeting last Thursday in Oro Valley Town Council Chambers.
Representatives from engineering firms and the towns of Marana and Oro Valley, Pima County and the Regional Transportation Authority were on hand to present the plan of access management strategies being used for planned reconstruction of the 10-mile stretch of Tangerine Road.
Alejandro Angel, vice president of traffic engineering for Psomas, a consulting engineering firm working on the project, said preliminary studies should be completed in 2012, with the final design and the first segment of construction taking place in 2013 or 2014.
The Tangerine Road project is part of the RTA plan approved by Pima County voters in 2006.
Angel noted the $74 million project will be funded by the RTA ($45 million) and the other three jurisdictions ($29 million).
Jim Schoen, senior principal engineer for Kittelson & Associates Inc., said the new roadway will be a four-lane desert parkway (two lanes in each direction), with multi-use bike lanes throughout and turn lanes at intersections.
Schoen noted that desert parkways are attractive roadways appropriate for developed or developing areas, as long as access to the roadway is managed well and planned in advance. Schoen solicited comments and feedback from citizens attending the meeting after the staff rolled out long aerial view maps of Tangerine Road overprinted with the planned roadway and access points.
Schoen pointed out desert parkways can be designed as either curbed or uncurbed. Uncurbed designs have a depressed landscaped median, no curbs on the median or road edge and typically are used on roadways with posted speed limits of 50 mph or greater, he said.
Curbed desert parkway designs have a curbed, landscaped median and uncurbed edge, but generally are intended for roadways with posted speed limits of 45 mph or lower.
Schoen added that at this time preliminary consideration is being given to using the uncurbed desert parkway design on the higher speed segment of Tangerine Road from I-10 to Thornydale Road or possibly only to the Dove Mountain Boulevard-Twin Peaks Road intersection. The remainder of the project westward to La Cañada Drive would use the curbed desert parkway design.
Access to the new road is critical in controlling how effectively it moves traffic, Schoen said. Joint-access driveways, frontage roads, and spacing of median openings and signals are methods planners will use to provide access, yet still keep traffic flowing smoothly, he pointed out.
Scott Leska, CIP engineering division manager for the Town of Marana, said an upcoming design concept report that will detail prevailing speeds on the road’s segments, along with public input, will help the project team determine the safest and most appropriate design for specific segments of the new roadway.
Noise will be mitigated along the roadway through use of rubberized asphalt to reduce the noise generated by tire and pavement friction. Noise walls are being evaluated, following standard methodology used for RTA projects.
Leska pointed out that one of the chief costs in a roadway project is the purchase of rights-of-way. While acquisition of rights-of-way will be needed for the Tangerine Road project, he said most acquisitions will come from undeveloped property owned by the Arizona State Land Department.
Partial acquisition of some private properties also will be needed, but project planners don’t anticipate that any homes, businesses or major structures will be affected.
Wildlife crossings will be built into the new roadway, according to Angel. The Arizona Game and Fish Department recently completed a Wildlife Mortality Study covering the area, identifying wildlife hotspots and making recommendations on accommodating wildlife crossing the roadway.
Angel said while sites are still being evaluated, preliminary plans are for large underground crossings approximately 10 feet high and 16 to 20 feet wide to handle larger animals such as mule deer and javalina, as well as smaller underground crossings of about 7 feet high and 10 feet wide for smaller animals.
Angel noted planners are trying to locate wildlife crossings in wash and drainage areas “where most of the vegetation and animals are located.”
For more information about the overall Tangerine Road Corridor project, visit www.tangerineroad.info.