Seattle Department of Transportation 2018 TRAFFIC REPORT *2017 data CONTENTS 5 Executive Summary 7 Traffic Volumes and Speeds 8 Motor Vehicle Volumes 11 Traffic Flow Map 13 Bicycle Volumes 18 Pedestrian Volumes 21 Motor Vehicle Speeds 23 Traffic Collisions 24 Citywide Collision Rate 25 Fatal and Serious Injury Collisions 27 Pedestrian Collision Rate 30 Bicycle Collision Rate 33 Supporting Data 33 Volume Data 44 Speed Data 48 Historical Collision Data 50 2016 All Collisions 54 2016 Pedestrian Collisions 63 2016 Bicycle Collisions 75 Glossary EXECUTIVE SUMMARY This report presents an end of year review of This report is prepared in compliance with Seattle the core data sets the Seattle Department of Municipal Code 11.16.220, which requires the Transportation (SDOT) collects and maintains City Traffic Engineer to present an annual traffic including volumes, speeds, and collisions. The report that includes information about traffic use of this data, guided by department plans and trends and traffic collisions on City of Seattle policies, serves as the foundation for making streets. Beyond this legal requirement, the informed decisions on nearly all work at SDOT report strives to serve as an accessible reference from safety improvements to repaving to grant of Seattle traffic data and trends for all. applications. It is fundamental to measuring project performance. The breadth and depth of In gathering and compiling the information the data collected allows objective discussion of in this report, the Seattle Department of project merits and results, be it a new crosswalk Transportation does not waive the limitations on or an entire safety corridor. As the demands and this information’s discoverability or admissibility complexity of Seattle’s transportation network under 23 U.S.C § 409. grow, the information supporting decisions about that network continues to expand and now For additional information about traffic data includes significant data on pedestrians, bicycles, and collisions on Seattle streets, readers may and trucks. contact the City Traffic Engineer Dongho Chang at [email protected] or visit the SDOT webpage at www.seattle.gov/transportation/. Linea Laird, Interim Director Dongho Chang, P.E., City Traffic Engineer Seattle Department of Transportation Seattle Department of Transportation 2018 TRAFFIC REPORT | 5 6 | SEATTLE DEPARTMENT OF TRANSPORTATION TRAFFIC VOLUMES AND SPEEDS The Seattle Department of Transportation (SDOT) collects and maintains volume data for vehicles Traffic volumes, speeds, and (including trucks), pedestrians, and bicycles. Engineers and planners use volume data to reported collisions are the three select future project locations, support grant cardinal pieces of data traffic applications, and track the performance of traffic projects once they are installed. engineers and planners use to evaluate changes to Seattle SDOT collects vehicle speed data in addition to volume data. Speed data is particularly useful streets. for making traffic safety decisions such as those connected with traffic calming, Safe Routes to School, Seattle’s Vision Zero Plan and crossing improvements. Speed data can also be reprocessed into vehicle classification data that categorizes vehicles in up to 13 different groups, including motorcycles, cars, and numerous types of trucks. Such data gives planners and engineers a better understanding of the movement of goods within the city. 2018 TRAFFIC REPORT | 7 MOTOR VEHICLE VOLUMES vehicle volume at 111 additional locations each SDOT is responsible for counting the volume of year. The locations of control, screen line, and traffic on certain city arterial streets each year. other regular counts are shown on maps in the Traffic counts are taken throughout the year at 20 appendix. SDOT also measures volume at ad control count locations, 164 screen line locations hoc locations throughout the year as needed for and 111 additional locations. traffic analysis and engineering studies. At 20 locations, SDOT conducts control counts Using the annual counts taken at 19 of Seattle’s every month. These counts are used to create bridges (including I-90, SR 520, and 1st Ave S), a monthly control factor. This factor can be SDOT derives a proxy number for citywide motor applied to every count we take to adjust for vehicle average daily traffic (ADT). Traffic volumes seasonal changes in traffic. In addition, SDOT decreased by 1.8% from 2016 to 2017. The measures vehicle volume at 164 screen line following graph of Seattle’s ADT shows overall locations. These locations are identified in trend since 2006. Population, employment, and Seattle’s Comprehensive Plan, and the counts transit ridership trends are also shown in graphs, are used to determine screen line levels of along with commute mode share for context. service as required by the plan. We also measure AVERAGE DAILY TRAFFIC IN SEATTLE 1,100,000 1,050,000 1,001,095 1,000,000 950,000 900,000 850,000 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 8 | SEATTLE DEPARTMENT OF TRANSPORTATION SEATTLE POPULATION 750,000 713,700 700,000 650,000 600,000 550,000 500,000 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 TRANSIT RIDERSHIP 180,000,000 170,580,780 170,000,000 160,000,000 150,000,000 140,000,000 130,000,000 120,000,000 110,000,000 100,000,000 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 TRAFFIC REPORT | 9 AVERAGE ANNUAL EMPLOYMENT SEATTLE, TACOMA, BELLEVUE 2,100,000 2,000,000 1,985,968 1,900,000 1,800,000 1,700,000 1,600,000 1,500,000 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2017 SEATTLE COMMUTE MODE SHARE* 1% 3% Drove Alone 11% Carpool Transit Walked Biked 51% 25% Other 9% *2017 American Community Survey 10 | SEATTLE DEPARTMENT OF TRANSPORTATION TRAFFIC FLOW MAP In 2017 the top ten arterials for traffic volume The 2017 Traffic Flow Map is one of the products include four streets that were not on the list in of the volume counts program. The volumes on 2016: Aurora Bridge, Mercer St east of Boren Ave the map represent the Average Annual Weekday N, N 130th St east of Ashworth Ave N, Lake City Traffic (AAWDT) (5-days, 24-hour) for that section Way NE south of NE 95th St, Fremont Bridge and of roadway. A full-size version of this map is Aurora Ave N north of N 68th St. The West Seattle available on SDOT’s website at: Bridge east of the Delridge ramps continues to be www.seattle.gov/transportation/document- the busiest city street, as measured by SDOT. library/reports-and-studies Top 10 Arterials by Volume Average Week Day Traffic (AWDT) West Seattle Bridge (EB&WB), west of Alaska Way Viaduct 100,642 East Marginal Way S, south of S Alaska St 70,352 Montlake Bridge 66,361 Aurora Bridge 61,998 Mercer St, east of Boren Ave N 60,926 Ballard Bridge 59,123 N 130th St, east of Ashworth Ave N 42,968 Lake City Way NE, south of NE 95th St 42,194 Fremont Bridge, north of Point A 41,716 Aurora Ave N, north of N 68th St 40,714 2018 TRAFFIC REPORT | 11 0 0 17 0 5 2 3 00 0 N 145TH ST NE 145TH ST 9000 13600 29500 29500 34000 16900 27000 27000 0 0 0 0 15 0 57 R 76 2017 Seat 0 0 tle O O 0 S 9 E 3 0 V 0 E E 9 d 0 L T N W 2 4 E 0 A 60 0 0 Y V 0 9 N 0 0 A 5 0 4 T L W E 8 3 2 S N 30 N 6 3 1 n E 0 0 E E 0 N 0 V Bitter V A A E 7 6 a Lake V H D 1 A Traffic Flow Map T 0 R 5 H 3 0 0 u T 0 0 5 4 3 65 k N 130TH ST 00 0 0 0 0 1600 12900 20800 21500 80 3 6 6 4 3 o 1 0 0 0 e 0 Average Annual Weekday Traffic D 0 0 3700 2000 0 0 E 60 N 6 0 6 1 9 60 S 95 2 3 S M Haller 00 O NE 125TH ST 3600 3500 8200 5500 R Lake 2500 18500 17700 12000 14400 NW 125TH ST E N 125TH ST 0 76 0 A 0 V 20 0 E 3 0 0 5 1 N 0 5900 0 N 4 6 0 00 0 0 0 0 0 0 1 0 0 E 0 0 0 0 0 0 0 V 00 0 0 7 6 9 0 0 0 0 A 5 0 120 0 0 3 0 , 7 , 0 5 0 0 50 N 4 0 1 , 5 0 0 0 0 2 1 W 3 , 0 0 2 , , A 0 I N 5 0 2 0 N 7 0 D 8 0 5 , 7 E I 0 E 0 E 0 , 9 N W V , R 1 2 0 V 3 A E Y A 5 5 0 N 115TH ST E A M 0 D N W NE 115TH ST 7 0 N R 9500 L 50 T O Measured Value Estimated Value 3 P 9 S 2700 1 t T R T 0 Y 0 S U 0 A 1 H 0 0 0 E 0 D 6 a 0 3 IN 7 5 2 P 1 3 1 e 00 98 5 00 0 0 10 E WAY 51 NE 110TH ST T 30000 29 44 7 3 A 300 18200 1 00 129 00 3000 s G 0 2000 3 3500 g H 2 T 0 R Annual Daily Traffic from WSDOT 32 O u N h Scaled the same are purple lines N N 105TH ST 0 0 0 0 0 0 22500 24900 5 P 0 00 E 0 0 0 9 5 1 N 8 1 24 i L 33 2 E P 00 0 V 0 0 0 H 1 8 9900 A T 0 0 0 0 17 0 E A 0 Miles 0 E 7 1 NE 103RD ST 2 n N N N 1 W 75 9 24 N 1 N 98 00 W Y E 0 0.15 0.3 0.45 0.6 E N 5400 7200 A V 00 N V R 5 0 A W D Y NE 100TH ST A NW 100TH ST 33 R T A 0 N N g O L H 0 T W T I E 5 E E R V 0 E 2 5 0 T NW 96TH ST 1 N E G 0 V 0 0 3 0 S E N A 2800 8 Y 0 L O A 02 8 0 7 0 0 1 L D 2 1 1 W O t 0 NE 9 1 85 5TH ST O O 2 R 9100 Y 00 7600 C 0 O 0 70 T I 0 0 0 8 W N 92ND ST C 0 60 0 6 0 0 N 422 7 7 E 10300 5 E o 40 500 0 88 8 W 7 E N K W R E D A R 00 N 00 L N 90TH N G ST 9 N E A W E E 13100 61 V 7 5 M 1 V 1 n L A O A 0 0 H 00 H 0 H 0 0 0 T T 8 5 2 0 3 0 240 7 10 0 18 4 1 N 85TH ST NW 85TH ST CO 0 3 7300 10500 14800 12800 17500 18800 23500 26300 39000 R 0 NE 85TH ST 12 0 L 0 I 6 0 3 S 1 2500 0 00 0 0 0 S 0 0 0 S 1 0 0 0 0 0 0 0 W 0 0 0 50 5 0 5 1 3 0 38 00 A 3 95 0 3 1 2 2 2 6 Y 8 E 9 2 0 4 1 0 1 00 3 0 N 0 00 N 4 NW 80TH ST 5 0 NE 80TH ST 66 E 0 3 0 10500 14600 14300 14000 15000 13800 23900 B V 0 00 A 2800 4700 96 A 17200 10000 6800 0 N 0 H 0 0 2 N N 0 0 E E T 0 0 0 AV E R 0 0 3 0 4 5 A 8 0 A 0 W 8 1 0 N S 0 O T 0 A 3 1 0 9 IN Y 7 0 G 0 W 9 W 0 2 N 0 NE 75TH 2 R ST 4 N 90 E E A E EN L KE 0 40 E 0 18100 W D 0 R 19500 2010600 17200 12300 5600 N 1 V 00 N 13000 80 N 60 77 A E 0 3 3 70 0 E 0 V W