7a_supp May 10, 2011 West Mercer Place Port of Seattle Commission May 10, 2011 SDOT Seattle Department of Transportation MERCER WEST Completing the Vision For Two-Way Mercer St From I-5 to Elliott Ave W WEST MERCER PLACE TWO-WAY CONVERSION MERCER UNDERPASS • Create a direct connection from I-5 and SR 99 to Seattle Center, Uptown, Queen Anne, and Interbay • Improve pedestrian and bicycle connection across 2 SR 99 • Add a new option for freight from I-5 to Interbay • Connect the Uptown and S Lake Union urban centers SDOT • Enhance transit access Seattle Department of Transportation MERCER WEST Existing Viaduct • Mercer connects to I-5 • Elliott connects to SR 99 in Belltown 3 Why consider changes to West Mercer Place? AWV Replacement / Bored Tunnel • Mercer connects to SR 99 & I-5 • Elliott connects to Alaskan Way SDOT Seattle Department of Transportation MERCER WEST Why consider changes to West Mercer Place? Limited pedestrian and bicycle connections No sidewalks or bike lanes on West Mercer Place 6 SDOT Seattle Department of Transportation MERCER WEST Left-turn lanes back up into through lanes Existing Conditions Existing Slide Area Residential Neighborhood Kinnear Park WEST MERCER PL Merge Point = SDOT-owned Right-of-Way 5 Steep Driveway Grades Up to 8% No Sidewalks SDOT Seattle Department of Transportation MERCER WEST 6 Potential Impacts: Existing Parking SDOT Seattle Department of Transportation MERCER WEST Analysis Kinnear Park WEST MERCER PL Potential Benefits: • Improve pedestrian and bicycle connection with Uptown • Reduce Delay o Mercer Street o Elliott Ave W 7 Potential Consequences: • Kinnear Park • Parking and Access • Walls • Noise • Cost SDOT Seattle Department of Transportation MERCER WEST New Sidewalk - extend to Elliott Ave W. Alternative 1 A B New Sidewalk 250' Retaining Wall A-B 8 SDOT Seattle Department of Transportation Uphill Bike Lane & New Sidewalk MERCER WEST Alternative 2 A New Bike Lane B New Sidewalk 330' Retaining Wall A-B 9 SDOT Seattle Department of Transportation MERCER WEST Extend the Merge Lane half-way up the hill Alternative 3 380' Retaining Wall A New Bike Lane B New Sidewalk 330' Retaining Wall Extend Merge Lane to Here A-B 10 SDOT Seattle Department of Transportation MERCER WEST Extend the Merge Lane to the top of the hill Alternative 4 Reconfigure Driveway 700' Retaining Wall A B 330' Retaining Wall New Bike Lane New Sidewalk Extend Merge Lane to Here A-B 11 SDOT Seattle Department of Transportation Extend the Left-Turn Lane Storage MERCER WEST Alternative 5 Extend Queue to 350 ft 225 ft Existing Queue Extend the southbound left-turn lanes on Elliott Ave W Compatible with all alternatives, including existing condition • Reduce delay • Reduce back-up on Elliott Ave W 12 SDOT Seattle Department of Transportation MERCER WEST Traffic Modeling Traffic Modeling Includes: SR 99 Bored Tunnel • Waterfront construction with Tunnel open (2016-2017) • Tunnel and Waterfront complete (2018) • Twenty-year growth (2030) Nickerson St / Dexter Ave N Population and Employment Growth • • • • Regional PSRC Forecasts Consistent with the Seattle Comprehensive Plan POS North Bay Alternative 4 (Industrial Development under existing zoning) 635 Elliott Ave Truck Volumes Cruise ship operations during the summer months RapidRide 13 SDOT Seattle Department of Transportation MERCER WEST AWV Peak Hour Traffic Projections At Elliott / W. Mercer Pl SB Elliott Ave Left-Turn 2010 SB Elliott Ave Through 2010 WB Mercer Pl 2010 NB Elliott Ave Through 2010 (1) "Waterfront Construction" = Tunnel is open to traffic. Construction on surface Alaskan Way. (2) "Program" = Tunnel open with surface Alaskan Way, Elliott/Western, and Mercer West Two-Way Conversion completed. 14 SDOT Seattle Department of Transportation MERCER WEST AWV AM Peak Hour Traffic Projections At Elliott / W. Mercer Pl SB Elliott Ave Left-Turn 2010 SB Elliott Ave Through 2010 WB Mercer Pl 2010 NB Elliott Ave Through 2010 (1) "Waterfront Construction" = Tunnel is open to traffic. Construction on surface Alaskan Way. (2) "Program" = Tunnel open with surface Alaskan Way, Elliott/Western, and Mercer West Two-Way Conversion completed. 15 SDOT Seattle Department of Transportation MERCER WEST AWV PM Peak Hour Traffic Projections At Elliott / W. Mercer Pl SB Elliott Ave Left-Turn 2010 SB Elliott Ave Through 2010 WB Mercer Pl 2010 NB Elliott Ave Through 2010 (1) "Waterfront Construction" = Tunnel is open to traffic. Construction on surface Alaskan Way. (2) "Program" = Tunnel open with surface Alaskan Way, Elliott/Western, and Mercer West Two-Way Conversion completed. 16 SDOT Seattle Department of Transportation Truck Volumes MERCER WEST Number of Trucks West Mercer Place / East of Elliott Avenue West 50 45 Actual Number of Trucks 40 35 30 8 25 3 20 7 3 9 15 4 21 10 5 2 0 7 8 5 26 18 11 18 3 13 11 7 0 6:00 7:00 8:00 9:00 10:00 11:00 12:00 13:00 14:00 15:00 7 1 16:00 3 1 17:00 Data Collected September 2010 (after the Nickerson St. re-channelization) 17 SDOT Seattle Department of Transportation Truck Percentages MERCER WEST Percent of All Traffic West Mercer Place / East of Elliott Avenue West Trucks as a Percent of ALL Traffic (%) 10% 8% 6% 6% 4% 4% 4% 4% 4% 3% 3% 3% 2% 2% 2% 1% 1% 0% 6:00 7:00 8:00 Data Collected September 2010 (after the Nickerson St. re-channelization) 18 9:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 Assumption for analysis: Trucks make up 5% of future a.m. peak period traffic volume on West Mercer Place. SDOT Seattle Department of Transportation Travel Time Savings MERCER WEST Future Condition: For Eastbound Traffic Alternative 3: Extend merge lane half way up the hill. Alternative 4: Extend merge lane all the way up the hill. Alternative 5: Extend left-turn lanes on Elliott Ave W. [Seconds saved] [Seconds saved] [Seconds saved] 2016: AM Peak Waterfront construction with Tunnel open. Autos: Trucks: 0 (0) 0 (0) 1 (1) 4 (3) 43 (41) * 52 (41) * 2018: AM Peak Tunnel and Waterfront Complete. Autos: Trucks: 0 (0) 0 (0) 3 (3) 5 (5) 4 (4) * 5 (5) * 2030: AM Peak Future condition. Autos: Trucks: 0 (0) 0 (0) 2 (2) 5 (5) 6 (7) * 13 (14) * Projected Travel Time: Elliott Ave W to I-5 without improvements on West Mercer Place 8 minutes (480 seconds) Cruise ship traffic volume travel time savings are shown in (parenthesis). • Alternative 5 Travel Time saving is reduction in delay for the left turn to West Mercer Place at Elliott. • Alternative 5 reduction in delay for southbound Elliott Ave would be 3 to 27 seconds 19 SDOT Seattle Department of Transportation Alternatives Summary MERCER WEST Travel Time Reduction: Kinnear Park Vehicle Entrance: Parking (approx # of spaces): Wall length: Noise: Estimated Cost: 20 Alternative 1: Add - 8 ft sidewalk. Alternative 2: Add - 8 ft sidewalk, - 5 ft bike lane. Alternative 3: Add - 8 ft sidewalk, - 5 ft bike lane, - Extend merge lane half way up the hill. Alternative 4: Add - 8 ft sidewalk, - 5 ft bike lane, - Extend merge lane all the way up the hill. Alternative 5: Extend left-turn lanes on Elliott Ave W 0 seconds 0 seconds 0 seconds 1-5 seconds 4-52 seconds - - Modified Modified - 4 11 11 23 / 4 - 250 ft south 330 ft south 330 ft south 380 ft north 330 ft south 700 ft north - - - Traffic lanes closer to homes Traffic lanes closer to homes - $2.7 Mil $4.2 Mil $8.0 Mil $12.9 Mil $0.2 Mil SDOT Seattle Department of Transportation MERCER WEST Mercer Corridor Schedule July 28, 2010 21 SDOT Seattle Department of Transportation MERCER WEST If you have any questions, please visit: http://www.seattle.gov/transportation/mercer_west.htm Or contact: Eric Tweit Mercer West Project Manager mercerwest@seattle.gov (206) 684-8834 22 QR code for the website SDOT Seattle Department of Transportation MERCER WEST 23 VISSIM Traffic Model Existing 225' Left-Turn Pockets SDOT Seattle Department of Transportation