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From page 233... ... 233 6.1 Introduction This chapter presents four case studies of project design processes that evaluate alternatives for improving the accommodation of all users (motorized and non-motorized) of a facility. Read the entire page →
From page 234... ... 234 Design Guide for Low-Speed Multimodal Roadways 6.2 Design Case Study A: Creating a Retail-Oriented Main Street This design alternatives case study for creating a retail-oriented main street is taken from Designing Walkable Urban Thoroughfares: A Context Sensitive Approach (ITE 2010a) Read the entire page →
From page 235... ... Case Studies: Designing for All Users 235 • Network pattern: grid; • Center turn lane: none; • Transit: low-frequency local route; • Bicycle facilities: not a designated bike route; • No landscaping; and • Conventional street and safety lighting. Stage 2: Understand community vision for context and thoroughfare. Read the entire page →
From page 236... ... 236 Design Guide for Low-Speed Multimodal Roadways 6.2.5 Factors to Consider/Potential Trade-Offs Factors to consider/potential trade-offs are: • Right-of-way constrained to 60 ft.; • Maximized parking using angled versus parallel parking (although change to angled parking may increase accidents and delays) ; • Reduction in the number of through lanes and vehicle capacity versus wider sidewalks and on-street parking; • Accommodation of large vehicles versus narrowing lane width and smaller curb-return radii to reduce pedestrian crossings; and • Accommodation of bicyclists versus width of other design elements. Read the entire page →
From page 237... ... Case Studies: Designing for All Users 237 4. Emphasize parking and vehicular capacity with parallel parking on both sides, 9-ft.-wide sidewalks, two travel lanes and a center turn lane. Read the entire page →
From page 238... ... 238 Design Guide for Low-Speed Multimodal Roadways Streetside: • 12-ft. sidewalks; • Pedestrian-scaled lighting; • Street trees in tree wells; • 6-ft. Read the entire page →
From page 239... ... Case Studies: Designing for All Users 239 Parallel Thoroughfares (as needed) : • Directional signing; • Operational adjustments or improvements; and • Physical improvements. Read the entire page →
From page 240... ... 240 Design Guide for Low-Speed Multimodal Roadways The AADT volume for Cascade Avenue is 22,000 VPD. It is a key arterial for three different fixed transit routes serving approximately 45 percent of the transit riders traveling within the city. Read the entire page →
From page 241... ... Case Studies: Designing for All Users 241 automobile and transit service. The key agency stakeholders are the city and local transit agency. Read the entire page →
From page 242... ... 242 Design Guide for Low-Speed Multimodal Roadways transit riders, pedestrians, and bicyclists. The four basic alternatives (including the existing condition) Read the entire page →
From page 243... ... Case Studies: Designing for All Users 243 to implement landscaping to help improve the aesthetics of the corridor. As will be seen in Alternative 3, the project team also considered changes that would provide additional designated space for pedestrians and bicyclists and create a buffer between pedestrians and bicyclists and moving vehicles. Read the entire page →
From page 244... ... 244 Design Guide for Low-Speed Multimodal Roadways • Reduce the capacity for automobiles from two lanes in each direction to one lane in each direction; • Remove on-street parking (as discussed previously) ; and • Increase sidewalk width for pedestrians. Read the entire page →
From page 245... ... Case Studies: Designing for All Users 245 6.3.6 Evaluation and Selection The performance categories evaluated for this project focus on the following: • Safety, as defined by crash frequency, crash severity and conflict points; • Mobility, as defined by average travel time; • Reliability, as defined by variation in travel time; • Accessibility, as defined by type and facility presence and transit service characteristics; and • QOS, as defined by MMLOS. To the extent feasible, the project team estimated the performance of each alternative quantitatively. Read the entire page →
From page 246... ... 246 Design Guide for Low-Speed Multimodal Roadways periods, as well as the Saturday midday peak period. The intent of including multiple periods was to obtain a sense of the range of travel time during low-, mid-, and high-traffic volume periods. Read the entire page →
From page 247... ... Case Studies: Designing for All Users 247 for managing conflicts between transit vehicles and bicyclists on approach to transit stops. This may include strategies such as moving the transit stop to a platform away from the sidewalk and having the bicycle lane pass between the platform and the sidewalk. Read the entire page →
From page 248... ... 248 Design Guide for Low-Speed Multimodal Roadways motorists from being stuck behind a transit vehicle loading and unloading passengers. The increased reliability is also attributable to removing the on-street parking present in Alternative 1. Read the entire page →
From page 249... ... Case Studies: Designing for All Users 249 cost-effectiveness factor, simplifying assumptions would be needed, and the city and project stakeholders did not want to oversimplify or omit performance measures they felt to be critical in selecting an alternative for Cascade Avenue. The city used the project cost information in combination with the performance evaluation results and understanding of the project context to reach consensus with project stakeholders on a preferred alternative. Read the entire page →
From page 250... ... 250 Design Guide for Low-Speed Multimodal Roadways Stage 1: Review or develop an Area Transportation Plan. 6.4.2 Existing Street Characteristics (see Exhibits 6-13 and 6-14) Read the entire page →
From page 251... ... Case Studies: Designing for All Users 251 Stage 2: Understand community vision for context and thoroughfare. 6.4.3 Vision Area plans envision a mix of high-density housing, retail centers and low-intensity commercial uses fronting the street. Read the entire page →
From page 252... ... 252 Design Guide for Low-Speed Multimodal Roadways • Alternative 2: Implement multiway boulevard with local access streets that provide on-street parking and shared bicycle/vehicle environment. This allows a wider streetside area and removes bicycles from higher-speed roadway. Read the entire page →
From page 253... ... Case Studies: Designing for All Users 253 Source: ITE (2010a) Exhibit 6-16. Read the entire page →
From page 254... ... 254 Design Guide for Low-Speed Multimodal Roadways 6.4.8 Solution Design Features Traveled Way: • Target speed: 35 mph; • Four, 11-ft. travel lanes in central roadway; • Parallel, 18-ft.-wide local access lanes separated by 8-ft.-wide landscaped medians; • Local access roads provide shared vehicle/bicycle lane and 9-ft. Read the entire page →
From page 255... ... Case Studies: Designing for All Users 255 Intersections: • Special design treatment required to accommodate multiple movements between central roadway and local access lanes; and • Intersections widened to accommodate left-turn lane within the central roadway. Parallel Thoroughfares (as needed) Read the entire page →
From page 256... ... 256 Design Guide for Low-Speed Multimodal Roadways to heavy-vehicle traffic. US-33 serves the existing industrial uses in the area while being a critical connection between the downtown and a regional park located to the north. Read the entire page →
From page 257... ... Case Studies: Designing for All Users 257 to address some of the deterrents for employers and explore ways to improve bicycle accommodations from the downtown area to the regional park. The city's basic approach for achieving this goal is to plan, design, and construct a new urban collector, 27th Avenue, within the newly zoned industrial area. Read the entire page →
From page 258... ... 258 Design Guide for Low-Speed Multimodal Roadways In addition to the roadway alignment, the project team focused on defining a set of crosssection design parameters that can be used to develop 27th Avenue. The cross sections must balance some of the performance trade-offs between access for heavy vehicles, quality of service for bicyclists and transit riders, and safety across modes. Read the entire page →
From page 259... ... Case Studies: Designing for All Users 259 parameters are focused on elements that provide sufficient space for heavy vehicles (as a form of accessibility) , quality of service for bicyclists and transit riders, and safety. Read the entire page →
From page 260... ... 260 Design Guide for Low-Speed Multimodal Roadways – Port (river) : Provides access to large merchant and freight-carrying ships with access to the ocean and, therefore, access to a wide range of global ports; and – Downtown: Connection to areas where employees will be traveling to and from their places of residence, and connection to existing transit service and bicycle boulevards. Read the entire page →
From page 261... ... Case Studies: Designing for All Users 261 Source: Ray et al. Read the entire page →
From page 262... ... 262 Design Guide for Low-Speed Multimodal Roadways The exhibits show there are a few common elements across the alternative cross sections: • A two-way center turn lane to facilitate access to future industrial uses fronting 27th Avenue; • Sidewalks to separate pedestrian activity and vehicle movement; and • One through travel lane in each direction, which was deemed sufficient given that 27th Avenue will primarily facilitate internal circulation. 6.5.6 Evaluation and Selection The performance evaluation for the alternative alignment options was based on each alignment's ability to: • Avoid significant environmental impacts; • Facilitate circulation and connections to regional transportation facilities; • Maintain contiguous parcels of land for industrial uses; and • Create an improved alternative route to the regional park. Read the entire page →
From page 263... ... Case Studies: Designing for All Users 263 Alignment 3 scored the highest based on the criteria because this alignment: • Avoids significant environmental impacts and establishes a western border for the newly zoned area. This means incoming industrial uses and employers will only be able to develop east of 27th Avenue. Read the entire page →
From page 264... ... 264 Design Guide for Low-Speed Multimodal Roadways why the project team also evaluated the quality of service for bicyclists and transit riders using the HCM 2010 MMLOS methodology. That methodology is sensitive to the presence and width of bicycle lanes and sidewalks. Read the entire page →

From page 233...

... 233 6.1 Introduction This chapter presents four case studies of project design processes that evaluate alternatives for improving the accommodation of all users (motorized and non-motorized) of a facility.