Module 10: Traffic Management Flashcards
Traffic Demand.
-Transportation is a demand that is derived from the connection of people & goods with activities.
Truths.
-Congestion costs economic & societal money
-Congested systems are unstable
-Given options, people will adapt to a given situation
–Barring a major wake up call, we are going to have to rely on the incremental but cumulative effects of many different initiatives
-It is going to take many individual measures, each contributing a marginal improvement, to keep the transportation system running in the face of expected growth
-We cannot build ourselves out of congestion
A Balanced Integrated Strategy.
-We can reduce congestion by focusing on three key strategies: strategically adding road capacity, operating the system we have more efficiently, & providing choices that help manage transportation demand
How can we Accommodate Travel Demand?
-Travel Demand Management: change amount, mode, time of travel
-Transportation System Management: Maximize existing capacity
Transportation System Management (TSM).
-TSM strategies improve the flow of traffic to reduce congestion without expanding the infrastructure itself
-TSM strategies can include physical changes to the roadway, changes to how the roadway is used.
TSM Examples.
-Intersection Improvements
-Street circulation changes
-Traffic signal improvements
-Traveller’s information
-Traffic/parking enforcement
-Managed lanes (HOV, HOT)
-Congestion pricing, etc.
Transit Priority.
-Reserved lanes, queue jump lanes, signal priority
-Transit priority has to be a major player - otherwise surface transit will be bogged down with the rest of the traffic
-Saving 5 minutes on a 60 minute round trip reduces travel time by 8%
Managed Lanes.
-Lane use can be managed in different ways to achieve different objectives:
-high occupancy vehicle lane
-high occupancy vehicle + tolled vehicle lane
-commercial vehicle lane
-Some key features
-separated by physical or painted buffer zone - designated access
zones
-on highways - in the median lane which is usually continuous & is
not crossed by other vehicles
-on arterial roads - in the curb lane which facilitates use by buses
-express/collector systems may not be amenable to managed
lanes
Managed Lanes - HOV.
-Objective is to reduce travel time for carpoolers using these lanes - encourages new carpools
-Increases person-throughput of lane if well-utilized
-Capacity lower than other lanes
-Require enforcement
-Varying degrees of success worldwide
-Best if supported by TDM measures
Managed Lanes - HOT.
-Using spare capacity in under-utilized HOV lanes
-Non-HOV’s allowed to use by paying a toll - provides them a “premium” service & increases utilization
-Ontario completed a feasibility & business case study on five 400 series highways
-Dynamic pricing - toll set to manage congestion in lane
-more congested - higher toll
-less congested - lower toll
Managed Lanes - CV Lanes.
-Can address multiple objectives:
-reduce effect of congestion on commercial goods movement
-improve apparent safety for auto drivers
-better pavement management
-would they be well utilized?
-Limited specific corridors may have potential utilization:
-serves 2 intermodal terminals
-serves an international airport
-serves industrial areas
Variable Speed Limits.
-Allows speed limits to be changed based on current road conditions
-Balance traffic to manage congestion & reduce crashes
-VSL display safe speeds for different travel conditions by adjusting posted speed limits based on real time traffic, roadway, or weather conditions
-By reducing the travel speed, it can actually improve travel times & reliability during congested conditions
-The dynamic VSL signs can change based on traffic & safety conditions. They are enforceable, regulatory speed limits; & not recommended speed advisories
Road Space Rationing.
-Also known as alternate day travel, driving restriction & no-drive days
-Restricting traffic access into city center, or district based upon the last digits of the license number on pre-established days & during certain periods, usually, the peak hours.
Road Pricing.
-Transportation pricing represents a user charge on road use - perhaps more equitable than use of tax dollars to build/maintain roads
-Area “congestion” charges, facility tolls, HOT lanes
-Need to consider socio-economic effects, e.g. retail businesses, resident within area effected
Area Congestion Charges.
-Fee charged on motor vehicles being driven into certain areas
Car Restrictions in City Centre.
-One of the most controversial aspects of the urban transport policy
-Some cities have closed their core central district to car traffic, at least on Saturdays. This involves establishment of peripheral parking areas & good transit, bicycle & pedestrian access
Travel Demand Management - Historical Definition.
-TDM is a series of specialized policies, programs, partnerships, & performance evaluation recommendations with the following primary goals:
-reduce automobile use by prioritizing walking, cycling, transit
-encourage travel during less congested time periods
-encourage the use of less congested routes
-change travel patterns to reduce or eliminate trips
A New Focus on Travel Choices.
-In addition to ridesharing, “managing demand is about providing travellers, regardless of whether they drive alone, with travel choices, such as work location, route, time of travel, & mode.”
-TDM means the use of strategies to inform & encourage travellers to maximize the efficiency of a transportation system leading to improved mobility & reliability, reduced congestion, & lower vehicle emissions
TDM.
-TDM is using the existing infrastructure in more efficient ways
-TDM is all about influencing people’s behaviour to use the existing built environment better
TDM - Provides Travel Choices
-Giving people multiple options provides them the freedom to do what they want, how they want, when they want
-Being able to access other transportation options allows commuters to more efficiently respond to the above behavioural factors
-By addressing any set of barriers, advocates, transportation, & cities can encourage large numbers of people to try smarter ways of travelling
Key Benefits of TDM - I.
Real Options for Commuters
-TDM programs & policies aim to provide commuters with a mix of
reliable & affordable transportation options. Supported with
effective marketing & advanced technologies, commuters can
make informed choices to meet each trips unique needs
Reduced Traffic Congestion
-With even a small reduction in the number of single occupancy
vehicles on our nation’s roads, commuters can see significant
reductions in congestion. TDM supports the most efficient use of
existing infrastructure by increasing per person throughput
Key Benefits of TDM - II.
Public Health & Safety
-With reduced reliance on personal vehicles, our communities will
see cleaner air leading to direct improvements in public health.
TDM initiatives that support increased levels of walking & cycling
also enhance overall quality of life
Connecting People to Jobs & Supporting Economic Activity
-With more commuting options & less traffic, people will have
better & more reliable access to jobs. Businesses will see increased
productivity from employees who spend less time in traffic
Understanding What Influences Choice.
-Understanding hat factors influence people’s decisions can help the transportation industry & advocates better show the benefits of different transportation options that address different components of motivations
-What motivates someone to bike, drive, or use transit? As the industry looks to influence demand, it’s important to recognize how commuters come to their decisions
What Influences Choice?
-Convenience
-Costs
-Flexibility
-Time
Other Factors that Contribute to Choice.
-Commute distance
-Environmental concerns
-Life events
Basic TDM Strategies.
-Commuter ridesharing
-Development mitigation
-Multi-modalism in transportation plans
-Maximizing travel choices
Broad Range of TDM Measures.
-Ridesharing
-Transit cost subsidy
-Bicycle friendly facilities
-Active transportation promotion
-Traveller information tools
-Pedestrian oriented design elements
-Road space allocation
-Park & ride
-Public transportation infrastructure improvements
-Parking
-etc
Transit Cost Subsidy.
-Transit benefits are associated with much higher ridership
-Employees offered commuter benefits are much more likely to take transit regularly
Parking Management Strategies.
-Revenue neutral abolishment of
-daily maximums
-early bird specials
-Parking enforcement
-Eliminate most minimum parking standards
-Introduce maximum parking standards
Shifting from Driving Alone - Measures.
-HOV lanes
-Dedicated bus lanes
-Protected bike lanes
-Priority parking for carpools
-Lowering off-street parking minimums
-Congestion pricing
-Monetary incentives to switch modes
-Carsharing
-Bikesharing
What are the Obstacles to Change Behaviour?
-People want to find better ways to commute, but not too many people shift their commuting behaviour:
-car commuters are not bearing the full financial cost of car
commuting
-taking transit or carpooling can benefit society, but it is often less
convenient for an individual commuter. It also takes time to plan
-it involves a habitual behaviour change which is notoriously
difficult to change
TDM - Trends.
-TDM strategies are also being incorporated into municipal policies & plans
-There is an opportunity to create innovative partnerships with third-[arty mobility service providers & technology companies
-Mandatory workplace programs for large employers
General Effectiveness of TDM.
-One size does not fit all
-TDM impacts are largely localized
-Travellers respond to their wallets
-Parking influences travel choices
-Packaging is key
TDM is not a Solution to All Transportation Problems.
-TDM can be highly effective at relatively low cost
-However, TDM is not adequate to solve congestion, air quality, energy, & other urban woes
-TDM is most effective at the localized level
-We need to integrate TDM strategies to congestion management
TDM vs TSM Similarities.
-Both serve the same aim of reducing traffic congestion, without utilizing more lands to build roads/lanes
-Both these policies look at ways to maximize the efficiency of the existing infrastructure without the need for addition of new & costly systems
-Both look into ways of providing a safer & more efficient transportation system for the public
TDM vs TSM Differences.
-TSM strategies focus on imposing physical changes to the infrastructure, and TDM targets traveller behaviour, mode choice, & employers to lower traffic demands on the roads during peak travel times.
-That is to say while drivers are obliged to conform to TSM measures, they have the choice of choosing to follow TDM measures.
-To an extent, the success of TDM measures is more dependent on individual motorist compared to success of TSM measures which rely more on the measures they implemented
-TDM seeks to modify demand to improve network conditions, TSM improves network conditions for a given level of demand
