2006

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2006 Congestion Report - Bellevue to Seattle (via SR 520)

The two graphs below display the percent of days on each route when traffic speeds fell below 35 mph. The darker line shows data for 2005. The lighter line shows data for 2003.

Morning Bellevue to Seattle via SR 520 graph displays 2005 data peaking at 55% around 7:45 a.m.between 7:15 a.m. and 9:30 a.m.compared to 2003 data peaking at 42% around 7:45 during the same time. Afternoon Seattle to Bellevue via SR 520 graph shows 2005 data peaking at 5:30 p.m. steadily increasing from 3 p.m. and dropping off at 7 p.m. compared to 2003 data peaking at 50% during the same time.

The graph below displays highway productivity for a specific point along this route. When the line is at 100%, the maximum number of vehicles per hour are travelling through this point. Any time the line dips below 100%, the system is not operating at 100% efficiency.

SR 520 Floating Bridge graph shows 2005 data dropping to a low of 55% around 10:15 a.m. bewteen 7 a.m. and 10:30 a.m. and to a low of 50% at 6:30 p.m. bewteen 2:30 p.m. and 7 p.m. The 2003 data is almost identical with slight time offsets being seen.

 

  Bellevue to Seattle AM Seattle to Bellevue PM
Route I-405/SR 520/I-5 I-5/SR 520/I-405
Peak time 8:40am 5:30 pm
Length 10.5 miles 10.1 miles
Travel time at posted speeds 11 minutes 11 minutes

Average Peak Travel Time 2003

18 minutes 18 minutes
Average Peak Travel Time 2005 19 minutes 21 minutes
Average Peak Travel Time Change, 2003-2005 6% 17%
95% Reliable Travel Time 2003 24 minutes 27 minutes
95% Reliable Travel Time 2005 28 minutes 33 minutes
95% Reliable Travel Time Change, 2003-2005 17% 22%
Ratio of Peak Travel Time to Maximum Throughput Travel Time (MT³I) 2003 1.4 1.4
Ratio of Peak Travel Time to Maximum Throughput Travel Time (MT³I) 2005 1.4 1.6
Traffic Volume Peak Hour Change -3% 0%
Duration of Peak Period, 2003 (hours:minutes) 1:15 2:25
Duration of Peak Period, 2005 (hours:minutes) 1:30 3:00
Change (in minutes) 15 35