Travel Costs Lecture 14 October 16, /

Value - travel time savings zMany studies seek to estimate VTTS yCan then be used easily in CBAs zBook reminds us of Waters 1993 (56 studies) yMany different methods used in studies yRoute, speed, mode, location choices yResults as % of hourly wages not a $ amount yMean value of 48% of wage rate (median 40) yNorth America: 59%/42%

Government Analyses zTypically 40-60% of hourly rate in CBAs zUS (FHA) 60% - Canada 50% zAgain, travel versus leisure important yWide variation: 1:1 to 5:1! zIncome levels are important themselves yVTTS not purely proportional to income yWaters suggests ‘square root’ relation yE.g. if income increases factor 4, VTTS by 2

Introduction - Congestion zCongestion (i.e. highway traffic) has impacts on movement of people & goods yLeads to increased travel time and fuel costs yLong commutes -> stress -> quality of life yImpacts freight costs (higher labor costs) and thus increases costs of goods & services yhttp://tti.tamu.edu/inside/hdv/programs/ama /mobility/study/report.stm (TTI report)

Literature Review zTexas Transportation Institute’s 1999 Annual Mobility Report y15-year study to assess costs of congestion yAverage daily traffic volumes yBinary congestion values x‘Congested’ roads assumed both ways yAssumed 5% trucks all times/all roads yAssumed 1.25 persons/vehicle, $12/hour yAssumed roadway sizes for 3 classes of roads yFour different peak hour speeds (both ways)

Results zAn admirable study at the national level zIn 1997, congestion cost U.S. 4.3 billion hours of delay, 6.6 billion gallons of wasted fuel, thus $72 billion of total cost zNew Jersey wanted to validate results with its own data

New Jersey Method zUsed New Jersey Congestion Management System (NJCMS) - 21 counties total xHourly data! Much more info. than TTI report yFor 4,000 two-direction links xFreeways principal arteries, other arteries yDetailed data on truck volumes yAverage vehicle occupancy data per county, per roadway type yDetailed data on individual road sizes, etc.

Level of Service zDescription of traffic flow (A-F) yA is best, F is worst (A-C ‘ok’, D-F not) zPeak hour travel speeds calculated yCompared to ‘free flow’ speeds yA-C classes not considered as congested yD-F congestion estimated by free-peak speed zAll attempts to make specific findings on New Jersey compared to national zhttp://

Definitions zRoadway Congestion Index - cars per road space, measures vehicle density yFound per urban area (compared to avgs) y> 1.0 undesirable zTravel Rate Index yAmount of extra time needed on a road peak vs. off-peak (e.g = 20% more)

Definitions (cont.) zTravel Delay - time difference between actual time and ‘zero volume’ travel time zCongestion Cost - delay and fuel costs yFuel assumed at $1.28 per gallon yVTTS - used wage by county (100%) yAlso, truck delays $2.65/mile (same as TTI) zCongestion cost per licensed driver yTook results divided by licenses yAssumed 69.2% of all residents each county

Details zCounty wages $10.83-$23.20 per hour zFound RCI for each roadway link in NJ yAggregated by class for each county

RCI result: Northern counties generally higher than southern counties New York City

TRI result: Northern counties generally higher than southern counties

Avg annual Delay = 34 hours! Almost a work Week!

Effects zCould find annual hours of delay per driver by aggregating roadway delays yThen dividing by number of drivers zTotal annual congestion cost $4.9 B yOver 5% of total of TTI study y75% for autos (190 M hours, $0.5 B fuel cost) y25% for trucks (inc. labor/operating cost) yAvg annual delay per driver = 34 hours

Future zPredicted to only get worse yCongestion costs will double by 2015