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TRAFFIC ENGINEERING SPEED STUDY George Elmer Drive City of Missoula, Montana Public Works Department May 2009 Background: George Elmer Drive was designed as an access road to serve the first phases of the 44 Ranch subdivision. The roadway was constructed in the summer/fall of 2007. Speed limits for the roadway were set during the design process and signed on the ground as part of the construction of the roadway. The speed limit was set at 45 miles per hour (mph) in 2007 by the City Public Works Department and the consulting design engineer. The 45 mph speed limit remains to this day between Mullan Road to the south and Cattle Drive to the north. Currently it remains an access road to only 44 Ranch subdivision but one other subdivision along the roadway is currently in design Ranch). At the time the speed limit was set in 2007, information was available to functionally classify this roadway. This information was contained within the 2004 Long Range Transportation Plan (LRTP) and the 2005 Wye Mullan West Comprehensive Area Plan (Comp Plan). The information presented in both publications helped to define the functional classification of the roadway to ultimately set a speed limit but were not consistent to exactly the classification (collector or arterial). The design of the 44 Ranch subdivision was another tool used to define functional classification of the roadway. 44 Ranch Phases 1 through 4 were approved with lots that fronted George Elmer Drive but those lots did not have access to George Elmer Drive. The subdivision was designed with limited access to George Elmer Drive to be consistent with the Comp Plan. The following bulleted items are excerpts from the LRTP and the Comp Plan that are related to and discuss the 'plan' for George Elmer Drive: LRTP Goal 1: Develop an interconnected, intermodal transportation network that provides reliability, equity, efficiency, choice, safety, and opportunity for all potential users. Goal 7: Implement and promote transportation system improvements that provide effective movement of people and goods. Objectives: Alleviate traffic congestion and reduce travel time for all modes between geographical areas within the metropolitan area. 'Wye/Mullan Plan Collector Routes' project is contained in Table 21 detailing all transportation improvements in the Missoula area by the planning year 2025. These collector routes, one of which is now George Elmer Drive, were in the recommended transportation plan projects ---PAGE BREAK--- category and were to be paid for principally from developer fees and assessments. The 'Wye/Mullan Plan Collector Routes' project meets goals 6 and 7 upon implementation. (Note Goal 6 is stated in the next section of this study.) Comp Plan Goal: Provide for safe, healthy, affordable, and efficient access to transportation systems. Map 6A-1 shows the major existing roads and future collectors in the plan area as well as transit routes, rail lines, and trails. It should be noted that George Elmer Drive is one of these collector roads shown on the map. Traffic is expected to increase approximately 35 percent by 2025 along Mullan Road, assuming completion of the Collector Roadway System and other improvements. With the recommended improvements, Mullan Road's projected 2025 operation level will be "approaching capacity" instead of the current level of "at capacity." Without the improvements, Mullan Road will be "over capacity" by 2025. (Note: At the time of George Elmer Drive construction the vehicle volume/counts for Mullan Road (just east of Lane) was 12,460. By 2025 that number may reach 16,820.) Developers of some recent large projects on Mullan Road have been required to conduct traffic analyses and build portions of the Collector Roadway System in order for the projects to proceed. From Lane to Cote Lane the recommendation for Mullan Road is for one travel lane in each direction plus an auxiliary lane (for left turns). The Board of County Commissioners adopted the Collector Roadway Resolution (#2001-005) on January 23, 2001. It shows general locations for future collector streets, non-motorized trails, and traffic controls in most of this plan area. The Resolution derives from the 1998 update to the Missoula Urban Comprehensive Plan and the 1996 Missoula Urban Transportation Plan Update, which envision growth in the plan area. Collectors are identified via the Collector Roadway Resolution and subsequent road easements. The Collector Roadway Resolution proposes a main east – west collector (England Boulevard) and a north – south collector (George Elmer Boulevard) to enable a connection between Old Highway 10 West, Interstate 90, and Mullan Road. The Collector Roadway System is intended to encourage traffic to flow northward and use Old Highway 10 West. Emphasis should be placed on the completion of George Elmer Road and England Boulevard as two significant connecting routes between the existing arterial systems. Completion of the grid will provide motorists with alternatives to Mullan Road and Reserve Street. Contained within Appendix 6A-2 is a Streetscape Matrix that lists an arterial classification for George Elmer Drive for Urban, Mixed Use and Heavy Commercial streetscape types. The arterial classification is also shown in this matrix for each of the streetscape types on Mullan Road. ---PAGE BREAK--- Collectors and arterials have different standards and along with adjacent land use can determine the classification. The following bulleted items are excerpts from the LRTP and the Comp Plan that discuss differences in standards along with factors that may affect a roadway classification: LRTP Goal 6: Promote and implement transportation system improvements that minimize the occurrence of ant the potential for accidents that might result in the loss of health, life, and property. Objectives: Develop a transportation plan that gives priority consideration to transportation system improvements that prevent accidents, reduce the number of conflicts, and minimize losses. Control access/manage corridors by looking at channelization and conflict management of high accident corridors and intersections. Access management is important in the preservation of capacity on existing transportation facilities. It is primarily accomplished by controlling adjacent land use and the locations of property access/local street connections. It is recommended that collectors have a mobility/access priority that has limited traffic mobility. Collector – approximate vehicles per day 1,000-8,000, typical speed limit 25-35 mph Minor Arterial – approximate vehicles per day 4,000-15,000, typical speed limit 30-45 mph Comp Plan Street and roadway facilities generally fall into a functional hierarchy based on the type of facility, its ownership, and the role it serves in the local and regional transportation system. The functional classification categorizes streets ranging from those that are primarily for travel mobility (arterials) to those that are primarily for access to property (local streets). The classification is useful for setting standards for right-of-way, spacing of driveways, defining intersections, setting speed limits, and implementing parking and other standards that preserve and enhance street function. Typically, roadways are grouped in the following general functional categories: Arterials emphasize a high level of mobility for through-movement. They serve major activity centers and provide service for the highest traffic volume corridors. The arterial system is further divided into urban or rural and principal or minor arterials, depending on function and trip making service provided. For example, the urban principal arterial system includes interstate highways, freeways, expressways, and other principal arterials. Urban minor arterials provide service for trips of moderate length and at a lower level of mobility and connect with urban principal arterials and rural collector routes. Collectors offer an intermediate level of service between local and arterial streets. They provide land access, collect traffic from local streets, connect neighborhoods to traffic generators and arterials, and serve as intra-area traffic corridors. The collector system is also divided into urban or rural and major or minor collectors, depending on function and trip-making service provided. Local Streets mostly provide direct access to adjacent land. They offer the lowest level of mobility and provide access to higher functionally classed roadways. ---PAGE BREAK--- The term "access management" applies to various measures that con improve road safety and the movement of vehicular traffic through the control and management of road access points. Examples of access management strategies include limiting the number of driveways to decrease turning conflicts, locating driveways as far from adjacent intersections as possible, providing adequate spacing between intersection streets, and using channels to preclude selected turning conflicts. Design: Access management has occurred on George Elmer Drive with the approval of both the 44 Ranch and Ranch Developments. Examples of access management for George Elmer Drive include no driveway having direct access onto the roadway, intersection control (roundabout at George Elmer Drive and Cattle Drive), and limiting local street access onto the roadway. Additionally, the roundabout is designed to reduce speeds to less than 25 mph so it acts as a speed regulating device. The preliminary plat for 44 Ranch and the design plans for George Elmer Drive both show a Future George Elmer Drive Typical Street Section. The 'typical section' configuration on the preliminary plat details a road width 52 feet from back of curb to back of curb. This width could incorporate 4-vehicular lanes with bike lanes and could be classified as an arterial. The 'typical section' configuration on the design drawings shows a different configuration from the preliminary plat and details a 12 foot landscaped median with one vehicular lane on either side of the median. This configuration could be considered a collector or arterial. The alignment of George Elmer Drive is straight from beginning to end. The roadway design took into account the flat terrain of the area and produced road grades less than 1.34%. The transition locations from positive grade to negative grade and back resulted in a maximum grade change of 1.89% and vertical curves were incorporated at all transition locations. This relatively flat and smooth transition design is appropriate for collector and arterial roadways. Additionally, the future asphalt thickness of 6" is planned for the roadway, when curb and gutter improvements are required with development of adjacent lands. This asphalt thickness is typical for arterial roadways. Conclusion: Based on the LRTP and the Comp Plan, George Elmer Drive was designed and constructed to either collector or arterial standards and could have a functional classification of a collector or arterial roadway. It is the recommendation of the Public Works Department to keep the existing speed limit of 45 mph on the roadway until other area subdivisions begin to access George Elmer Drive. New subdivisions along George Elmer Drive will result in new intersections which may provide traffic calming or roundabout improvements that can physically reduce speeds. When additional access to George Elmer Drive occurs in the future, a speed limit study that looks at the future speeds and accident history among other factors can be completed. An appropriate speed limit can be set based on that future speed limit study.