Transportation planning

Learning objectives

• Explain what metropolitan planning organizations do and the plans and programs they produce.
• Describe functional classification and the tradeoff between mobility and access.
• Put the four steps of the conventional travel demand model in order and explain each one.
• Compare level of service and vehicle miles traveled as measures, and explain induced demand.
• Apply complete streets, road diets, Vision Zero, transit-oriented development, and travel demand management.
• Explain the basics of transit service planning, parking policy, and access management.

Key concepts

Who plans transportation

• State departments of transportation (DOTs) plan, build, and maintain state highways and distribute federal funds. Each state prepares a long-range statewide plan and a Statewide Transportation Improvement Program (STIP).
• Metropolitan planning organizations (MPOs) are federally required for every urbanized area with a population of at least 50,000. They carry out the "continuing, comprehensive, and cooperative" (3C) regional planning process. An MPO's board typically includes local elected officials, the state DOT, and transit operators.
• Transit agencies plan and run bus and rail service.
• Local governments plan and manage local streets, sidewalks, parking, and land use.

12 more sections follow in the full lesson.

Key terms

• MPO: The federally required regional transportation planning body for urbanized areas of 50,000 or more people.
• Transportation Improvement Program (TIP): The MPO's short-range, fiscally constrained program of funded projects.
• Fiscal constraint: The requirement that plans and programs fit within reasonably expected revenue.
• Transportation conformity: The demonstration that transportation plans are consistent with air quality plans.
• Functional classification: Grouping streets as arterials, collectors, and locals by function.
• Four-step model: Trip generation, trip distribution, mode choice, and trip assignment.
• Gravity model: A trip distribution method based on zone size and separation.
• Level of service (LOS): A letter grade of traffic operations, from A to F.
• Vehicle miles traveled (VMT): Total miles driven by vehicles in an area and period.
• Induced demand: Additional driving generated by added road capacity.
• Complete street: A street designed for safe use by people of all ages and abilities in all modes.
• Road diet: Reallocating lanes, typically from four lanes to two plus a center turn lane.
• Vision Zero: A strategy to eliminate traffic deaths and serious injuries.
• Transit-oriented development (TOD): Compact, mixed-use development within walking distance of transit.
• Travel demand management (TDM): Strategies that reduce or shift travel demand.
• Headway: The time between transit vehicles on a route; shorter headways mean more frequent service.
• Ridership versus coverage: The tradeoff between concentrating transit where it attracts the most riders and spreading it to reach more places.
• Farebox recovery ratio: The share of transit operating costs paid by fares.
• Complementary paratransit: ADA-required service for riders whose disabilities prevent them from using fixed-route transit.
• Unbundled parking: Parking rented or sold separately from the housing or space it serves.
• Shared parking: Parking used by different uses whose demand peaks at different times.
• Access management: Controlling the location and design of driveways, medians, and turns along a road.