I-794, Lake Freeway Bicycle/Pedestrian Feasibility Study
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1300-13-19 I-794 LAKE FREEWAY BICYCLE / PEDESTRIAN FEASIBILITY STUDY DRAFT B-40-400 OCTOBER 2011 DRAFT [Page Intentionally Left Blank] This document is designed for two-sided (duplex) printing. DRAFT I-794 Lake Freeway Bicycle/Pedestrian Feasibility Study Milwaukee County EXECUTIVE SUMMARY INTRODUCTION In accordance with policy set forth by the Federal Highway Administration (FHWA), as well as state laws and policies, the Wisconsin Department of Transportation (WisDOT) is evaluating the feasibility of adding a shared-use path to the Daniel Hoan Bridge (Hoan Bridge) as part of the rehabilitation project expected to begin in 2013. This study includes an evaluation of the feasibility of alternatives for a shared-use path along Interstate 794, Lake Freeway (I-794), specifically along the Hoan Bridge. I-794 LAKE FREEWAY (HOAN BRIDGE REHABILITATION) PROJECT SCOPE WisDOT is moving forward on a project to make major improvements to the Hoan Bridge and the I-794 Freeway. This project is divided into three segments: 1. I-794 East-West (Milwaukee River to the Lake Interchange) • Remove and replace bridges with new structures 2. Lake Interchange (I-794 East-West to the Hoan Bridge) • Overlay concrete and repair concrete surface 3. Hoan Bridge (Lake Interchange to Lincoln Avenue) • Remove and replace the existing bridge deck and make structural modifications • Blast, clean, and repaint the bridge steel Though the Hoan Bridge deck replacement project currently does not include the addition of a shared-use path to the bridge, certain FHWA and state guidelines recommend investigating the feasibility of adding a shared-use path to projects involving a bridge redeck. EXISTING CONDITIONS EVALUATION The Hoan Bridge in its existing condition is 108 feet wide and consists of three 12-foot wide travel lanes in both the northbound and southbound directions. In both directions of travel, the left shoulder is 6 feet wide and the right shoulder is 10 feet wide. The bridge is currently (2011) limited to two lanes going both northbound and southbound due to ongoing maintenance projects. The posted speed limit is 50 miles per hour. The Hoan Bridge currently accommodates motor vehicle traffic; bicyclists and pedestrians are prohibited on the bridge. The Milwaukee County Oak Leaf Trail currently acts as the primary bicycle trail connecting the Bay View neighborhood to Downtown. The trail is off-road at Cupertino Park and transitions to a route along a series of municipal streets at Russell Avenue at the south end of the Hoan Bridge. Traveling along the variousDRAFT municipal streets north to Michigan Avenue, the off-road segments of the trail resume along the west side of Lincoln Memorial Drive and along Lake Michigan, east of the Milwaukee Art Museum and north of the Discovery World Museum. At the north end there is also a connection to the Hank Aaron State Trail at Lakeshore State Park. DESIGN ELEMENTS WisDOT standards state that the shared-use path on a high-speed facility such as the Hoan Bridge would require that the shared-use path be separated by a barrier. Further, the shared- use path must comply with other design and safety measures which include compliance with the Americans with Disabilities Act (ADA). E - 1 I-794 Lake Freeway Bicycle/Pedestrian Feasibility Study Milwaukee County Given the engineering focus of this study, design criteria were developed based on engineering guidelines accepted by both FHWA and WisDOT. The resources include: • WisDOT’s Facilities Development Manual (FDM) • WisDOT’s Bridge Design Manual • WisDOT’s Bicycle Facility Planning Handbook • AASHTO’s Guide for the Development of Bicycle Facilities • AASHTO’s A Policy on the Geometric Design of Highways and Streets • AASHTO’s A Policy on Design Standards – Interstate System • FHWA’s Manual on Uniform Traffic Control Devices DESCRIPTION OF ALTERNATIVES The original scope of the current study addressed four alternatives to provide a shared-use path on the Hoan Bridge. These alternatives were studied by WisDOT and the consultant team and have been expanded to include additional sub-alternatives. Of the 11 total alternatives analyzed, six were eliminated as infeasible. The five alternatives that were carried forward in the study are described below. Alternative 1 Alternative 1 involves adding a shared-use path on the existing roadway of the Hoan Bridge/I 794 structure without increasing the width of the bridge. This alternative would require the assignment of at least one travel lane to accommodate the shared-use path, resulting in the reduction in motor vehicle travel lanes on the bridge. Alternative 1A Alternative 1A involves the reduction of the I-794 northbound lanes from three to two travel lanes and the addition of a shared-use path for bicyclists and pedestrians located on the east side of the bridge. Alternative 1B Alternative 1B involves the reduction of I-794 northbound lanes from three to two travel lanes and the addition of a shared-use path for bicyclists and pedestrians in the center of the structure. Under this alternative, the shared-use path would be offset from the centerline of the structure. Alternative 2A Alternative 2A involves a shared-use path on the east side of I-794. This would involve widening the bridge on the approach spans, curving out around the horizontal tie girder on the main span, and attaching the shared-DRAFTuse path to the east side of the horizontal tie girder of the bridge. This alternative does not require a reduction in the number of travel lanes along I-794. Alternative 3B Alternative 3B proposes the construction of an additional elevated structure above the existing roadway of the Hoan Bridge. Like Alternative 2A, it does not require a reduction in travel lanes along I-794. Alternative 4 Alternative 4 involves the construction of a separate shared-use structure adjacent to I-794. E - 2 I-794 Lake Freeway Bicycle/Pedestrian Feasibility Study Milwaukee County EVALUATION OF ALTERNATIVES Impact on Traffic Operations Because alternatives 1A and 1B include a reduction in vehicular travel lanes, this feasibility study includes an analysis of existing and future traffic operations along the Hoan Bridge. WisDOT developed design year (2035) traffic forecasts using sound technical methodologies. The forecasts included a 0.8% annual growth rate based on recent traffic growth trends on the Hoan Bridge as well as a modest 0.5% annual growth rate that considered the potential for a future growth rate lower than the recent trend. The Southeastern Wisconsin Regional Planning Commission (SEWRPC) independently developed a 2035 traffic forecast from a regional travel simulation model based on forecasts of land use, population, and transportation facilities. The SEWRPC forecast also equated to a 0.8% annual growth rate. This approach provided the basis for performing sensitivity analysis for future traffic operations. The current Hoan Bridge configuration of three traffic lanes in each direction operated during the year 2010 peak hour at level of service (LOS) ‘C’. If a traffic lane was removed in either direction (alternatives 1A and 1B), the Hoan Bridge is anticipated to have operated at LOS ‘D’ to ‘E’. Construction on the Hoan Bridge in 2011 resulted in motorist diversion, which lessened the overall operational impacts. Under the three-lane configuration, the Hoan Bridge is anticipated to operate at LOS ‘C’ to ‘D’ in 2035. Alternatives 1A and1B will require the reduction of one northbound lane along the I-794 corridor between the Lake and Carferry Drive interchanges. If a traffic lane is removed in either direction the Hoan Bridge is anticipated to operate at LOS ‘E’ to ‘F’ in 2035. The latter result is below WisDOT’s acceptable design year standard of LOS ‘D’ for Milwaukee County freeways. These conditions would worsen over the 50+ year life of the investment. Structural Feasibility An important element of determining the feasibility of each alternative is assessing the structural adequacy. Each alternative presented was modeled based on the depictions shown in the renderings and other details to determine the feasibility of constructing a shared-use path on the existing I-794 structure. Assumptions and simplifications were made in the individual analysis in order to identify “fatal flaws” of the alternatives presented. The alternatives were investigated for an occasional single maintenance truck utilizing the shared-use path to facilitate snow removal and routine maintenance. In addition, all alternatives, except for 3B, were evaluated to support the use of a UB vehicle to be utilized for inspection of the structure. To assess structural feasibilityDRAFT of each alternative, the following items were considered: • Existing structural capacity and rating • Additional loading applied to the structure • Reduction of existing structural capacity and rating • Required retrofits to existing structural elements All of the alternatives referenced in this summary were determined to be structurally feasible. However, due to additional loading, significant retrofits of the structural components of the existing Hoan Bridge would be required for alternatives 2A and 3B. While this study indicates E - 3 I-794 Lake Freeway Bicycle/Pedestrian Feasibility Study Milwaukee County that both alternatives are feasible, further design analysis on the main span’s complex tied-arch system may result in additional changes. North and South Access Locations The evaluation of the feasibility of adding a shared-use path to the I-794 corridor must also consider safe access and network connectivity to trails and municipal streets within the study area. A review of existing facilities indicates that a new shared-use path along the I-794 corridor would have logical connection points to Milwaukee trail facilities and municipal streets at the following locations: • At the south end of the study area, an off-road segment of the Milwaukee County Oak Leaf Trail is located at the intersection of East Russell Avenue and South Lincoln Memorial Drive in Cupertino Park.