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I I I I I I I I I I I I I I I I I I I Project Issues It is our understanding that the City of Sunny Isles Beach wishes to provide a bridge structure connecting North Bay Road across an unnamed canal between NW 172nd Street and NW 174th Street. In the near term, the bridge structure is intended to be reserved for pedestrians and occasional emergency vehicle traffic. In the future, it is anticipated that additional right-of-way will be available which will allow the bridge to be opened to everyday vehicular traffic. At that time, the City wishes to make the conversion to a traffic bearing bridge with minimal modification to the structure. Design Criteria Although this project will be developed as a predominantly pedestrian facility, it will require the underlying infrastructure that will allow for the future conversion to traffic. This two phase development of the project will ultimately drive the decision making process of the project design. Ultimately, the underlying design criteria for the future vehicular phase of the bridge will determine most of the design decisions for the project. The structural loading, structure width, alignment, tie-in and pedestrian safety are all aspects that will be more critical in the end result than in the near-term pedestrian phase. To accommodate this future requirement, it will be necessary to plan and design this project for its ultimate vehicular configuration. Once the infrastructure for the future vehicular project is designed, the pedestrian facilities can be applied as an overlay to this skeleton. The bridge will be designed following AASHTO LRFD Bridge Design Specifications and HL-93 loading and pedestrian loading. All roadway design will be performed in accordance with the "Florida Greenbook" Manual of Uniform Minimum Standards for Design, Construction and Maintenance for Streets and Highways (May 2005) as well as the AASHTO "Policy on Geometric Design of Highways and Streets, 2004" Geometric and Alignment Issues Although the Structural and Environmental issues will ultimately drive this project, the fundamental issue of alignment and geometry must be determined first and foremost. Ultimately, this determination will directly impact the degree of complexity for both the bridge structure and the environmental permitting. At this time, the complicating factor in projecting this alignment is the uncertainty related to the property boundaries and easements. While the beginning and end point of the corridor are known, the path between them will depend greatly on where encroachment on private property is allowed. According to information made available to respondents, the City has a 20' easement between the condominium buildings to the south. According to available tax records, the existing property lines run north-south between the buildings but make several jagged turns as they approach the canal. Due to these variations in the property lines, the actual layout of the easement is unclear. The exact layout of this easement will be one of the first crucial steps required to set a proper alignment. Due to the offset nature of the alignment, the structure will be required to skew across the canal with a reverse curve. The severity of the skew increases dramatically depending on how this path is aligned between the end points. The configuration of this easement will determine how the bridge will angle onto the southern shore and eventually curve south to meet 172nd Street If the alignment is allowed to cross on the most direct route, the crossing would meet the southern seawall and follow the existing sidewalk around the building to 172nd Street. This would result in the shortest bridge structure and would minimize impacts to the mangrove fringe farther east. However, Page 1 of 7