TECHNICAL MEMORANDUM Albany - Washington Avenue Traffic Calming Evaluation Matrix of Conceptual Alternatives Date: May 17, 2017 Project #: 17356 To: Aleida Andrino-Chavez From: Laurence Lewis, Sara Muse, Evan Reed, and Lee Rodegerdts This technical memorandum provides a summary of a range of alternatives proposed for the Washington Avenue corridor between Pierce Street and Cerrito Street in Albany, California. The evaluation begins with a summary of the guiding objectives for the evaluation, followed by summary evaluations at the segment and intersection levels. OBJECTIVES Four primary objectives have been identified for this corridor for use in this evaluation: Provide a pedestrian pathway along the corridor Minimize loss of on-street parking for residents Reduce speeding along the corridor Reduce the potential for cut-through traffic along the corridor A fifth objective, other considerations, has been added to capture considerations not captured by the four primary objectives. FILENAME: H:\PROJFILE\17356 - ALBANY (CA) WASHINGTON AVE TRAFFIC CALM\RESPONSE TO DEC 2016 CONCEPTS\EVALUATION MATRIX OF ALTERNATIVES - 2017-05-16.DOCX
Albany - Washington Avenue Traffic Calming Project #: 17356 May 15, 2017 Page 2 SEGMENT CONCEPTS Concept Objective Parking Restrictions along Midblock Raised Convert Segment to One Way Provide Selected Parking Cut-Outs (Neighborhood Concept presented at Segment (Red Curb) Crosswalk December 2016 Community Meeting)* Provide pedestrian pathway Restores use of existing sidewalk by removing parking on sidewalk No impact on pedestrian path away from midblock crossing Restores use of existing sidewalk by removing one travel lane and shifting parking from sidewalk back to street Restores use of existing sidewalk or provides minimum-width sidewalk adjacent to new parking cut-outs Minimize loss of parking Reduce speeding Reduce potential cut-through traffic Removes substantial amount of parking Parking impact limited to only the vicinity of crosswalk for visibility of Parking is maintained Provides up to 16 stalls along the length of the corridor pedestrians Speeding may increase due to lack of friction on the side of Raised crosswalk reduces speeds in the vicinity of the Speeding eliminated in the direction of travel that is prohibited the street with parking restrictions crosswalk; little impact away from crosswalk Speeding may increase in the direction of travel due to absence of conflicting flow No effect likely No effect likely Cut-through traffic eliminated in direction of travel that is prohibited Retention of parking and minimum clear width likely to provide sufficient friction to minimize excessive speeding No effect likely
Albany - Washington Avenue Traffic Calming Project #: 17356 May 15, 2017 Page 3 Objective, cont. Other considerations (includes cost and schedule) Parking Restrictions along Segment (Red Curb) Can be implemented at very low cost Shortest implementation timeframe Midblock Raised Crosswalk Can be implemented at low to moderate cost Short implementation timeframe Convert Segment to One Way *A fatal flaw evaluation of each proposed parking stall is included as an appendix. Can be implemented at low to moderate cost Moderate implementation timeframe Significant out-of-direction travel induced for residents (likely environmental impact due to increase in vehicle miles traveled [VMT]) Reduced lane widths would likely impact emergency vehicle response time Provide Selected Parking Cut-Outs (Neighborhood Concept presented at December 2016 Community Meeting)* Can be implemented at moderate to high cost Longest implementation timeframe Most parking stalls appear to have moderate to significant challenges for implementation (0 with high feasibility, 10 with medium feasibility, 10 with low feasibility). Challenges: o Retaining walls likely needed for several proposed parking stalls due to side slopes, which adds substantially to costs and impacts to landscaping. Order of magnitude costs for a 2 ½ ft. tall retaining wall are $70 to $200 per linear foot. o Some parking stalls may need to be shifted to avoid utility poles o Some proposed stalls are too short relative to existing driveway locations o One proposed stall is located within an intersection
Albany - Washington Avenue Traffic Calming Project #: 17356 May 15, 2017 Page 4 INTERSECTION CONCEPTS Concept Objective All-way stop control at Parking Restrictions Bulb-outs at Mini-Roundabouts Raised Crosswalk at Entrance Barriers (without Gateview Avenue and at Intersections Intersections Intersections segment restrictions to one- Pierce Street (Red Curb) way travel) Provide pedestrian pathway Minimize loss of parking Reduce speeding Reduce potential cutthrough traffic No effect Required by California law to provide visibility of pedestrians at intersections No effect Loss of 20 feet of parking upstream, 7 to 10 feet downstream Possible localized reduction in speed but minimal over segment Low probability of conflict increases potential for running stop signs Potential reduction in cutthrough traffic Higher visibility of pedestrians at intersection crossing locations, less exposure to vehicular traffic Parking restrictions in the vicinity of the bulbout No effect likely due to localized impact Narrow width of roadway between bulb-outs is likely to reduce through speeds and especially turning speeds in the vicinity of the bulbout Crosswalks located further away from intersection Larger parking impacts at intersection due to splitter islands on each approach Minimal speed reduction effect is likely due to inability to provide proper design within site constraints Provides more visible crossing location No additional parking impacts beyond those required by California law (red curbs) Reduces through and turning speeds at intersection Wider sidewalks possible in the vicinity of the barrier Parking will likely be impacted in the vicinity of the barrier Requires cars to alternate to pass through barrier, which likely will induce a significant speed reduction Likely environmental impact due to increase in vehicle miles travel (VMT) No effect likely No effect likely No effect likely No effect likely Cut-through traffic eliminated in direction of travel that is prohibited
Albany - Washington Avenue Traffic Calming Project #: 17356 May 15, 2017 Page 5 Objective, cont. All-way stop control at Gateview Avenue and Pierce Street Parking Restrictions at Intersections (Red Curb) Bulb-outs at Intersections Mini-Roundabouts Raised Crosswalk at Intersections Entrance Barriers (without segment restrictions to oneway travel) Other considerations (including cost and schedule) Minimal cost Not warranted in California MUTCD due to insufficient vehicular volume Minimal cost Facilitates emergency vehicle access Likely to impact turning movements of emergency vehicles and waste collection vehicles Emergency vehicle and garbage truck turning movements need to be carefully evaluated Largest impact area of intersection alternatives None noted Increased potential for head-on collisions Minimum width needed for emergency vehicles and garbage trucks
LEGEND High Feasibility Medium Feasibility Low Feasibility
WASHINGTON CERRITO 16 15 14 13 WASHINGTON LEGEND High Feasibility Medium Feasibility Low Feasibility 12 11 10 POLK
Page i APPENDIX Parking Concept Fatal Flaw Analysis The fatal flaw analysis represents a general evaluation of the parking concept s feasibility. The analysis is intended to address the most critical transportation engineering issues and is based on a review of available base mapping and aerial photos. It does not include a complete review of vertical elements, underground elements, or specific right-of-way boundaries. The following standards and design constraints apply to this evaluation: The community concept has proposed a clear travel width of 14 ft. Note that the California Fire Code requires a clear width of 20 ft. to allow emergency vehicles to pass. The community concept has proposed parking stalls that are 6.5 ft. wide by 15 ft. long. If a 6.5 ft. stall is used, portions of the vehicle such as mirrors may extend into the travel way. Note that the City of Albany uses a width of 7 to 8 ft. for parking stalls. A transition taper is needed between the existing curb and the recessed curb at each end of the parking cutout and is assumed to be at a 45-degree angle. As a result, approximately 12 ft. is needed to provide transition tapers for a parking cutout that is recessed by 6 ft. The community concept has proposed parking stall lengths of 15 ft. Not that the City of Albany uses a minimum length of either 15 ft. (one space) or 18 to 20 ft. (two or more spaces in tandem). For one or two vehicles in a parking cutout, it is our opinion that 15 ft. parking spaces are minimally feasible with 6 ft. transition tapers behind or in front of vehicles. If there are more than two vehicles in a parking cutout, the interior parking spaces should be 20 ft. long to enable ingress and egress between parked vehicles. The following feasibility scoring system has been used: Feasibility Score = High if all of the following are true: Cross Section Width - minimum cross section width exists based on the dimensions provided in the community concept: 6.5 ft. parking stalls, 4 ft. sidewalks, and 14 ft. travel lane, as measured in CAD; Parking Stall Length minimum 15 ft. per stall exists plus transition tapers and a length allowance for interior parking spaces in a series of three or more as noted above; Conflicts no physical conflicts exist (other than observed shrubbery or minor landscaping); and Adverse Conditions - no adverse conditions exist (i.e. sight line impacts, stall located in/near intersection, require retaining walls, etc.). Feasibility Score = Medium if any of the above exist that can be reasonably accommodated or mitigated. Feasibility Score = Low if any of the above exist and cannot be readily mitigated.
Page ii Parking Stalls 1, 2, & 3, between Pierce Street and Gateview Avenue Feasibility Score = Medium Cross Section Width: Minimal (See Figure 1) Parking Stall Length: Adequate for two standard stalls, slightly too short for three minimum stalls (48 available after including two 6 transition tapers, which allows stalls of 24 and 24 or 15, 18, and 15 ). Conflicts: Potential utility pole conflict with Stall 1 (possibly avoidable); significant landscaping Adverse Conditions: Will need a retaining wall approximately 2-2.5 high due to side slope Figure 1: Supporting CAD snip for stalls 1, 2 & 3
Page iii Parking Stall 4, between Pierce Street and Gateview Avenue Feasibility Score = Low Cross Section Width: Minimal (see Figure 2) Parking Stall Length: Not feasible (only 12 ft. available between driveways) Conflicts: Adjacent driveways Adverse Conditions: Very small parking space due to adjacent driveways Figure 2: Supporting CAD snip for stall 4
Page iv Parking Stall 5, between Pierce Street and Gateview Avenue Feasibility Score = Medium Cross Section Width: Minimal (See Figure 3) Parking Stall Length: Adequate (leaves 25 ft. for one standard stall after including two 6 transition tapers) Conflicts: Utility pole, could likely be avoided due to length of stall; landscaping Adverse Conditions: Would likely require a retaining wall due to side slopes Figure 3: Supporting CAD snip for stall 5
Page v Parking Stalls 6 & 7, between Pierce Street and Gateview Avenue Feasibility Score = Medium Cross Section Width: Minimal (See Figure 4) Parking Stall Length: Adequate (leaves 32 ft. for two minimum stalls after including two 6 transition tapers) Conflicts: Landscaping; sight distance constraint (Stall 7 is approximately 13 from intersection) Adverse Conditions: Significant landscaping; likely requires a retaining wall Figure 4: Supporting CAD snip for stalls 6 & 7
Page vi Parking Stalls 8 & 9, between Gateview Avenue and Polk Street Feasibility Score = Medium for 8, Low for 9 Cross Section Width: Meets 14 minimum width and CA Fire Code travel lane standard of 20 Parking Stall Length: Adequate for one minimum stall only (18 available after including two 6 transition tapers (See Figure 5) Conflicts: None Adverse Conditions: Nearing an intersection; likely requires retaining wall. Stall 9 blocks a driveway for 839 Washington and is not feasible. Figure 5: Supporting CAD snip for stalls 8 & 9
Page vii Parking Stall 10, at Polk Street Feasibility Score = Low Cross Section Width: Significantly more than 14 minimum, but still does not meet CA Fire Code 20 standard. Parking Stall Length: Adequate (20 for Stall 10 but constrained with crosswalk and intersection) Conflicts: Intersection Adverse Conditions: Located in an intersection. Sight distance constraint. Not Feasible. Figure 6: Supporting CAD snip for stall 10
Page viii Parking Stall 11, between Polk Street and Cerrito Street (north side of street) Feasibility Score = Low Cross Section Width: Significantly more than 14 minimum, but still does not meet CA Fire Code 20 standard. Parking Stall Length: Adequate. No sight distance conflicts, as it is 22 from existing crosswalk Conflicts: Utility Pole. Adverse Conditions: Utility pole impact. Parking Stalls 17 & 18, between Polk Street and Cerrito Street (south side of street) Feasibility Score = Medium Cross Section Width: Adequately more than 14 minimum, but still does not meet 20 standard. Parking Stall Length: Adequate (68 available for three standard stalls) Conflicts: Significant landscaping, irrigation, new concrete sidewalk and curb, existing crosswalk. Adverse Conditions: Located adjacent to intersection. Figure 7: Supporting CAD snip for stall 11, 17, & 18
Page ix Parking Stalls 12 & 13, between Polk Street and Cerrito Street (north side of street) Feasibility Score = Low Cross Section Width: Signficantly more than 14 minimum, but still does not meet CA Fire Code 20 standard. Parking Stall Length: Adequate for two standard or three minimum stalls (53 available after including two 6 transition tapers) Conflicts: Significant landscaping, steep side slopes Adverse Conditions: Likely to require retaining wall on northwest side Parking Stall 19 & 20, between Polk Street and Cerrito Street (south side of street) Feasibility Score = Low Cross Section Width: Signficantly more than 14 minimum, but still does not meet CA Fire Code 20 standard. Parking Stall Length: Adequate for two minimum stalls (32 available after including two 6 transition tapers) Conflicts: Significant landscaping; relocation of School sign for Stall 20 Adverse Conditions: N/A Figure 8: Supporting CAD snip for stalls 12, 13, 19 & 20
Page x Parking Stall 14, between Polk Street and Cerrito Street Feasibility Score = Medium Cross Section Width: Minimal (see Figure 9) Parking Stall Length: Adequate for one minimum stall (17 available after including two 6 transition tapers) Conflicts: Significant landscaping, steep side slopes Adverse Conditions: Retaining walls on northwest side Figure 9: Supporting CAD snip for stall 14
Page xi Parking Stall 15, between Polk Street and Cerrito Street Feasibility Score = Low Cross Section Width: Minimal (see Figure 10) Parking Stall Length: Adequate for one minimum stall (17 available after including two 6 transition tapers) Conflicts: Significant landscaping, fence impacts; potential building impacts, manhole Adverse Conditions: Retaining walls on west side, impacts to house/building Figure 10: Supporting CAD snip for stall 15
Page xii Parking Stall 16, between Polk Street and Cerrito Street Feasibility Score = Low Cross Section Width: Minimal (see Figure 11) Parking Stall Length: Adequate for one minimum stall (17 available after including two 6 transition tapers) Conflicts: Significant landscaping, fence impacts potential building impacts, existing utility pole Adverse Conditions: Retaining walls on northwest side. Figure 11: Supporting CAD snip for stall 16
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