Design Primer

Design Primer

Design Primer Central City in Motion Project Volume 1 Twelve issues that will influence design and therefore planning 1) Intended User 2) Our Unique Grid 3) Left/Right Bike Facilities 4) Progression and Flow 5) Transit Integration 6) Curbside Uses 7) Stormwater Compliance 8) Utility Infrastructure 9) Signal Technology 10) Emergency Services 11) Loading and Hauling 12) Urban Design Districts DESIGN PRIMER central city in motion project PORTLANDOREGON. GOV/TRANSPORTATION 2 DESIGN PRIMER central city in motion project PORTLANDOREGON. GOV/TRANSPORTATION 3 The bikeway network will be designed for people of all ages and abilities. (TSP Policy 9.21) DESIGN PRIMER central city in motion project 4 INTENDED USER PORTLANDOREGON. GOV/TRANSPORTATION • The existing network is mostly comprised of Level of Traffic Stress (LTS) 3 facilities. • Achieving the City’s aspired levels of growth and vitality will require that most (over 80%) people get around the Central City without the use of a private car. • For most people to make this choice, the streets must be low stress: safe, comfortable, and inviting for walking and biking. • CCIM will target improvements that meet the LTS 2 and LTS 1 levels. DESIGN PRIMER central city in motion project 5 INTENDED USER PORTLANDOREGON. GOV/TRANSPORTATION Block Scale = Access Friction Portland’s small block structure (200’ x 200’ typ.) increases the number of intersections and the quantity and frequency of land use access ways onto the right-of-way. This consequence of our unique urban fabric increases the “friction” between movement along a linear bicycle facility and movements across the bicycle’s path. DESIGN PRIMER central city in motion project 6 OUR UNIQUE GRID PORTLANDOREGON. GOV/TRANSPORTATION Street Width = Conspicuous Compromise Portland’s uniquely narrow right-of-way make the allocation of space within the street particularly constrained and challenging. The sameness of design and lack of modal hierarchy within the many streets of the grid means that repurposing space will have a network-level effect. The tightness of available space accelerates the need for choices between modes more quickly than in other peer cities. DESIGN PRIMER central city in motion project 7 OUR UNIQUE GRID PORTLANDOREGON. GOV/TRANSPORTATION Couplet System in the Grid A one-way grid with a couplet circulation system means that vehicle turning movements across a bicycle path of travel happen every two blocks, regardless of whether the bicycle facility is on the left or right side of the street. There is no magic bullet for lane assignment within the one-way grid. DESIGN PRIMER central city in motion project 8 OUR UNIQUE GRID PORTLANDOREGON. GOV/TRANSPORTATION Variety in the lane assignment or placement of the bicycle facility (left side running, right side running or center running) will be needed in response to context such as: • Frequent high-usage driveways • Unique property access requirements • Free right vehicular turning movements • Bridgehead and freeway ramp entries • Major bus transit stops and sidings • Surface rail alignments/lane assignment DESIGN PRIMER central city in motion project 9 LEFT/RIGHT FACILITIES PORTLANDOREGON. GOV/TRANSPORTATION Accommodating bicycle turning movements within a one-way grid is complex. Right turns are generally easier than left turns. But when bicycle facilities within the grid occur on different sides of different streets (i.e. left running on 2nd Avenue but right running on Stark), the complexity increases. It is expected that for different streets and different contexts, left running facilities will be preferable. And it is expected that on certain streets (perhaps where there is NOT any bus transit service) that right running facilities will provide the better option. Therefore, the resolution of turning movements within the protected bicycle network will require multi-phase turns with necessitated dwell time for bicycles, or dedicated bicycle phases that allow bicycle turning movements in lieu of green time for vehicles. DESIGN PRIMER central city in motion project 10 LEFT/RIGHT FACILITIES PORTLANDOREGON. GOV/TRANSPORTATION RIGHT-SIDE BIKE LANES Where there is significant curbside activity, such as transit stops, high-turnover parking, or loading and unloading zones, vehicles may frequently cross in and out of the bike lane, thus compromising comfort and safety for bicyclists. DESIGN PRIMER central city in motion project 11 RIGHT-SIDE BIKE LANES PORTLANDOREGON. GOV/TRANSPORTATION LEFT-SIDE BIKE LANES On one-way streets, installing the bike lane on the left side is an alternative that can reduce conflict between bicyclists and transit vehicles, heavy volume right turn movements, or vehicles that need to access the right-side curb. DESIGN PRIMER central city in motion project 12 LEFT-SIDE BIKE LANES PORTLANDOREGON. GOV/TRANSPORTATION • The traffic management system in the Central City – particularly the west side – is a complex network of inter-related signals. • The timing of the system manages speed and flow of vehicles in all four directions within the one-way grid/couplet construct. • Utilizing signal time for bicycle movements will have network-level effects. • Introducing long contraflow bicycle corridors (i.e. two-way cycle tracks) within the westside signal progression is not feasible. DESIGN PRIMER central city in motion project 13 PROGRESSION & FLOW PORTLANDOREGON. GOV/TRANSPORTATION • In a one-way signal progression, as used in Downtown Portland, signals are timed so that vehicles can “hit all the greens” and maintain flow at about 12 miles per hour. • In this example, eastbound vehicles maintain flow, hitting green through the intersections, and the signals are on a 50- second cycle. DESIGN PRIMER central city in motion project 14 PROGRESSION & FLOW PORTLANDOREGON. GOV/TRANSPORTATION • Introducing a contraflow movement, such as a two-way cycle track with one direction moving against the flow of one-way traffic, exposes the contraflow movement to substantial delay. • In this example, westbound bicycles are subject to up to 20 seconds of delay at red lights every two blocks. DESIGN PRIMER central city in motion project 15 PROGRESSION & FLOW PORTLANDOREGON. GOV/TRANSPORTATION • Clarifying the spatial and operational relationship between bus transit and protected bicycle facilities is paramount. • A range of tools, developed in the Enhanced Transit Corridors Plan, will be needed in different places within the Central City. • Examples of solutions could include: • Lane configurations and markings • Bus stop placement and arrangement • Enhanced stations with separated bicycle facilities • Shared environments at transit stops DESIGN PRIMER central city in motion project 16 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION BIKE-BUS CONFLICT The main conflict between bus operations and bicyclists is that both modes of transportation often need to utilize the same part of the road at bus stops. Buses pull to the right of the road to pick up waiting passengers, forcing bicyclists to stop behind the bus or merge into adjacent travel lanes. ! DESIGN PRIMER central city in motion project 17 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION BIKE-BUS CONFLICT Side-boarding island stops eliminate bike-bus conflicts while facilitating accessible in-lane stops and reducing pedestrian crossing distances. DESIGN PRIMER central city in motion project 18 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION SHARED SPACES With constraints in the right-of-way and overlapping needs for transit service and protected bicycle facilities occurring on the same stretch of street, hybrid right side solutions may need to be adopted. DESIGN PRIMER central city in motion project 19 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION Channelized bicycle lanes along bus islands may be more comfortable for bicyclists. DESIGN PRIMER central city in motion project 20 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION Raised bicycle lanes may be appropriate in some areas to provide a larger clear zone for wheelchair users loading and unloading from the transit vehicle. DESIGN PRIMER central city in motion project 21 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION Streetcars, which have fixed paths, must stop in lane, and therefore require floating boarding islands where there is an adjacent bikeway. DESIGN PRIMER central city in motion project 22 TRANSIT INTEGRATION PORTLANDOREGON. GOV/TRANSPORTATION • Access to the sidewalk/curbside is critical for many street users and existing land uses. • Preservation of many access and curbside uses is key to the vitality of the Central City. • Balancing need for access with protection for people riding bicycles is a key design challenge at: • Non-redundant driveways • Loading/trash/recycling service entries • ADA parking • Hotel zones, event frontages • Fire hydrants DESIGN PRIMER central city in motion project 23 CURBSIDE USES PORTLANDOREGON. GOV/TRANSPORTATION DESIGN PRIMER central city in motion project 24 CURBSIDE USES PORTLANDOREGON. GOV/TRANSPORTATION DESIGN PRIMER central city in motion project 25 CURBSIDE USES PORTLANDOREGON. GOV/TRANSPORTATION • The City of Portland has important criteria for stormwater management in the right-of-way. • Clarifying the thresholds of reconstruction and reconfiguration of the street with the addition of protected bicycle facilities will be key to cost- effective implementation. DESIGN PRIMER central city in motion project 26 STORMWATER COMPLIANCE PORTLANDOREGON. GOV/TRANSPORTATION • Full reconstruction

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