presentation at the 15 th trb national transportation planning applications conference atlantic...
TRANSCRIPT
Forming Third-Party Speed Data for use in
a Congestion Monitoring Plan
Presentation at the 15th TRB National Transportation Planning Applications Conference
Atlantic City, NJMonday, May 18th
Nick Wood, P.E. Texas A&M Transportation Institute (TTI)
From TTI:
Joan Hudson Boya Dai Shawn Turner
Cathy Stephens and the CAMPO staff
Acknowledgements
Background and Introduction
CMP is a Federal requiremento Systematic framework for analyzing & incorporating
congestion management into planning process
CAMPO uses a Roadway Congestion Analysis to meet part of that requiremento Six counties in Central Texas, surrounding Austin
o Conducted every two years
Old methods are problematico Floating car method is limited
o New technologies can be harnessed
2012 Roadway Congestion Analysis
New to the Roadway Congestion Analysis o RFP issued for speed datao Variety of sources– third-party providers and in-
house Bluetooth readers o Volume weighting – higher volume roads have a
higher rankingo Performance measures
Extent of Studyo Over 1,300 centerline miles includedo 942 segmentso 2.8 miles in length on average
RFP for Roadway Speed Data
TTI issued RFP on behalf of CAMPO for historical speed data
Required Specificationso Speed data shall be provided for 2012 yearo Data provided in a table and GISo 15-minute intervalso Averaged by day of weeko Key metrics (min, max, percentiles)
Two vendors responded
Data Sources and Description
Motor vehicle speed datao 2012 INRIX TMC (traffic
message channel)o 2013 INRIX XD Traffico Anonymous Wireless
Address Matching (AWAM) with Bluetooth readers, Feb 2014
Coverage issues Differences in years were
noted in final report
Methodology for Analysis
Segmentationo Shorter segments in densely populated urban areaso Medium segments in suburban areaso Longer segments in rural areas
Conflationo Match the motor vehicle volume data to the speed datao Allows for volume-weighting
Rolling peak periods o 2-hour worst total delay selected from 6-10am, 3:30-
8:30pm Reference speeds based on non-congested travel
or speed limit (whichever is lower)
Rolling Peak Periods
Created because peak of congestion occurs differently for different parts of the region
Example: A Policy Board Member from an outlying area may be unhappy with limited time period based on CBD.
PM Peak Periods (Selected)
Performance Measures Average speed Travel time index (TTI)
Planning time index (PTI)
o Both 80th and 95th percentiles were used
Delay per mile Total delay (vehicle-hours, by peak
period) Total delay per mile
Results 1,300 miles of roadway Average delay
o 200,000 vehicle-hours per weekday
Annual delayo Only 2012 TMC: 44
million veh-hourso Including 2013 xD:
48 million veh-hours o Including Bluetooth:
Total of 52 million veh-hours
Most Congested - PM Peak Period
Rank Roadway Travel Direction
Total Delay (veh-hr)
Start End Segment Length (Miles)
1 IH 35 S 4676.51 E 26th St E 15th St 2.41 2 IH 35 S 3826.51 Airport Blvd E 26th St 2.69 3 IH 35 S 1944.65 E 15th St E 1st St 0.98 4 IH 35 N 1926.15 E Riverside Dr E 1st St 0.92 5 IH 35 N 1395.34 E 1st St E 15th St 0.98 6 US 183 N 1352.53 Loop 1/Mopac Expy Duval Rd 2.86 7 IH 35 N 1315.90 E 15th St E 26th St 2.53 8 IH 35 N 1188.68 E Oltorf St E Riverside Dr 1.03 9 IH 35 N 1121.04 Braker Ln E Parmer Ln 2.21
10 IH 35 S 1120.00 US 290 E Airport Blvd 2.39 11 IH 35 N 984.29 E 26th St Airport Blvd 2.87 12 Loop 1/Mopac Expy N 955.36 Windsor Rd W 35th St 1.06 13 Loop 1/Mopac Expy S 942.23 W 35th St W 45th St 1.08 14 Loop 1/Mopac Expy N 768.91 W 5th St Enfield Rd 0.71 15 Loop 1/Mopac Expy S 745.17 RM 2222 W 45 St 1.42 16 Loop 1/Mopac Expy S 740.60 W 35th St Windsor Rd 0.93 17 Loop 1/Mopac Expy S 732.75 Bee Caves Rd S Capital of Texas
Highway 1.97
18 Loop 360/Capital of Texas Hwy
S 701.39 Bee Caves Rd S Mopac Expy 3.72
19 IH 35 S 680.13 E 1st St E Riverside Dr 0.92 20 IH 35 S 653.12 E Riverside Dr E Oltorf St 1.03 21 IH 35 N 649.77 Airport Blvd US 290 E 2.51 22 Loop 1/Mopac Expy S 627.86 W 5th St Bee Caves Rd 1.18 23 Loop 1/Mopac Expy N 594.39 W 35th St W 45th St 1.02 24 Loop 1/Mopac Expy N 562.03 Windsor Rd Enfield Rd 0.45 25 US 183 S 513.18 Springdale Rd FM 969 2.40
Top 50 Most Congested Roadway Segments - PM
Lessons Learned Travel times runs are problematic
o Costly to collecto Not longitudinally representative
Quality Control is Important!o Flat line speed profiles are not good
Visualization helps to tell the storyo Make an effort to create eye-popping graphics
Future CMPs and analyses will rely more on combing different data sources togethero Formats and methodologies will likely not matcho Document the limitations
Questions
Contact info:o Nick Wood, P.E., [email protected] Joan G. Hudson, P.E.,
[email protected] Boya Dai, [email protected] Shawn Turner, P.E.,