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All Correspondence DCS ItemFrom:Sue Prant To:boulderplanningboard Subject:Boulder"s Design and Construction Standards (Agenda Item) Date:Tuesday, December 1, 2020 12:26:29 PM Attachments:Suggestions for DCS update.pdf External Sender Dear Planning Board, Community Cycles is pleased to see progress in updating the transportation elements of the Boulder's Design and Construction Standards to reflect the city's values and goals, and to embody up-to-date engineering knowledge about transportation, especially for long-neglected non-motorized modes. Many of Community Cycles' comments to the Board over the years have been necessitated, in our view, by inadequate or outdated design standards, so we are hopeful that the update will make creating safe, equitable, and sustainable transportation infrastructure easier. Your memo indicates the focus in 2021 will include section 2.07 on street design, which we support. It says that other areas of focus include median landscaping, content of engineering reports, and restoring pavement cuts. While these latter areas are clearly important, we would like to suggest that revising other street-design sections that have a direct impact on street safety, namely 2.06 (Base Street and Alley Standards) and 2.09 (Residential Streets), is a higher priority. We feel there would be considerable efficiency in considering these three sections together. In fact they could probably most sensibly be combined into a single section, or at most two sections, especially since 2.06 explicitly excludes residential streets and therefore only seems to apply to the streets covered by 2.07. And we consider the residential/nonresidential distinction to be an outmoded relic of strict separation of land uses, which as you know the city is gradually moving away from, as evidenced by the Board's recent work to update the Use Standards. We are eager to see much-needed updates to section 2.08 (Sidewalks). However, we understand that the Pedestrian Advisory Committee will be considering this section and providing suggested changes in the coming year. We look forward to seeing the PAC's recommendations and having the consultant able to take on this section in 2022. Last, in selecting a consultant we would like to suggest that the city specifically reach out to Speck & Associates for a proposal. Jeff Speck is the author of, among other books, Walkable City Rules, which is itself sort of a lay version of an ideal design standard for building a people-friendly city (and we encourage you to peruse it if you haven't already). The world is full of good planners, of course, but in our view Speck is one of the best and of the caliber that Boulder deserves. Thank you. Community Cycles Advocacy Committee PS We have attached our recommendations for updates to Sections 2.07 & 2.08 -- Sue Prant Executive Director Community Cycles 2601 Spruce Street, Unit B Boulder CO 80302 Shop phone: 720-565-6019 Direct line: 303-564-9681 e-mail: sue@communitycycles.org www.CommunityCycles.org Join the movement! Become a Community Cycles member Subscribe to our monthly e-news! Suggestions for revision of Boulder's Design and Construction Standards Section 2.07 1.The current DCS gives detailed criteria for street design but does not provide any background information as to the purpose of the design choices. We suggest that there be a discussion of the goals of street design and how the design choices align with the TMP and Vision Zero. This will provide guidance for when there are engineering choices to be made and might allow for some context-sensitive flexibility (subject to approval by the Director). A focus on pedestrian and bike safety and efficiency should be emphasized (e.g., minimal crossing distances, physical protection, allocation of space, etc.). The City of Boulder's Parks and Recreation Department has a very nice ​park design standards document​ that is easily readable and provides great background information and many graphical examples of design objectives. We recommend that the Transportation DCS follow this example. 2.In particular, this section should include clear and comprehensive standards for intersections, as intersections are where most traffic crashes take place, and produce the most user stress for bicyclists and pedestrians. Intersections should be designed with pedestrians as first priority (minimizing crossing distance and maximizing their safety and mobility), followed by bicyclists, buses, then SOVs, as described in the TMP. As an example, right-turn bypass lanes are incompatible with pedestrian-first design, and they should therefore be disallowed. 3.Chapter 2.07 should include standards for warrants and design of protected bicycle facilities. This includes protected bike lanes, protected intersections, and multi-use paths. These design standards should be based on current best practices from NACTO, MassDOT, and non-AASHTO sources. The design standards should provide clear graphical representations and focus on the purpose of the designs (protecting bicyclists, improving bicycle LOS, and attracting the "interested but concerned" cohort). We recommend that a protected intersection be required wherever a Low Stress Network route intersects with an arterial or collector street. 4.2.07(C): Lane Width. Lane width should not be fixed. The context of the street (e.g., neighborhood commercial center, light industrial, non-commercial arterial) is critical in apportioning space for motor vehicles and people biking and walking. The design speed of the street, based on intended use, should be determined first. In Table 2-5, there should be a range of travel lane widths depending on the design speed of the street, with guidance indicating that the minimum width allowable should be used, to reduce crossing distance, maintenance costs, and heat-island effect. The width of bike lanes should be based on the Low Stress Network guidelines. Physically protected lanes should be used when appropriate criteria in the LSN are met. 5.2.07(D)(5)(c): Intersections and Street Spacing. It is not appropriate to recommend signalized intersections at 1/2 mile intervals. This is clearly a relic of suburban, auto-centered AASHTO guidance. It has no place in Boulder. 6.2.07(D)(5)(d): Corner Radii: The DCS should specify maximum corner radii in addition to or in place of the minimums. This should vary by design speed and be chosen to provide the maximum protection possible to vulnerable road users like pedestrians and cyclists, and to allow pedestrians to travel in a straight line through an intersection without having to divert to access ramps. 7.2.07(D)(7): This section skips the initial question of whether an intersection should include turn lanes at all. There need to be clear criteria for when turning lanes are required. When is a left turn lane warranted? When is a right turn lane warranted? The purpose of adding turn lanes needs to be clearly stated, and needs to be aligned with the TMP. Is the purpose motor vehicle LOS? Is this aligned with the TMP pyramid of priorities, with pedestrians on top and single-occupancy vehicles on the bottom? Space needs to be left for protected intersections for bicyclists and pedestrians. How is this balanced against motor vehicle LOS? 8.2.07(D)(7)(a): Storage Length. Again, these specifications need to be aligned with the goals of the TMP, where LOS is not the primary goal. Does adding storage length affect other modes? Is there room left over for protected bike infrastructure? We recommend the intersection be designed to accommodate vulnerable users first, then storage length can be added as needed, if width is available. If it's not available, that is an acceptable outcome based on TMP guidance. 9.2.07(E)(3): This table is based on a design speed of 30mph, which is not appropriate for residential streets with speed limits of 20mph. It should include provision for design speeds below 30mph. 10.2.07(F): Sight Distance. We feel that sight distance at intersections and driveways is currently not adequate. There are many places where parking, landscaping, and signage impinges unacceptably upon sightlines. There are many, many examples around town; we'd be glad to discuss these with Staff. "Sight Triangles" in Sect. 9-9-7 of the B.R.C. 1981 should be revisited and recommendations for modifications recommended to Council. Section 2.08 1.This section should include sidewalk reconstruction standards, particularly thresholds for the scale of work beyond which sidewalks are not to be replaced in-kind, but to be brought up to the standards of this section. This should include constructing detached sidewalks to current width standards and replacing rollover curbs with standard protective curbs. 2.2.08(A): Every street, without exception, must welcome pedestrians. That means either providing well-designed, well-maintained sidewalks, or a street designed as a woonerf that ensures motor vehicle speeds that are compatible with safe, comfortable walking. It should not be acceptable for a street to simply opt out of providing an adequate pedestrian environment. 3.2.08(B): This subsection needs clear thresholds for when on-street sidewalks are required to be constructed or brought to the current standard. Any project, including those that do not go through site review, above a given dollar-value threshold should be required to provide sidewalks meeting current standards. 4.2.08(C): The standards should require that sidewalks enable pedestrians to travel in as straight and direct a path as possible, avoiding unwarranted shifts or jogs. This includes curb ramps, which should allow pedestrians to travel across an intersection in line with the sidewalks on either side. This would benefit all pedestrians, but especially those in wheelchairs, with limited mobility, or with visual impairments. 5.2.08(D): The entries for 4 and 5 in this table should be increased to 5 and 6, respectively, to provide adequate space for pedestrians to walk side-by-side and to clear obstructions. 6.2.07(E): This subsection should include standards for maximum transverse grade, which is particularly relevant where driveways cross sidewalks.