Land use transportation cycle

The land use-transportation cycle shows that land use and transport affect each other in a repeated loop.

   Land use (houses, shops, offices) <----------+
        |                                       |
   creates trips                         land use changes
        v                                       |
   Travel demand                         Accessibility and
        |                                land value rise
        v                                       ^
   Transport facilities (roads, transit) -------+

Steps of the cycle

1. Land use generates trips: the type, size and location of activities (residential, commercial, industrial) decide the number of trips and their origins and destinations.
2. Trips create travel demand on the transport network, leading to traffic and congestion.
3. Transport facilities are built or improved (new roads, public transport) to meet the demand.
4. Accessibility improves along the new facility, so some areas become more attractive.
5. Land use changes: land value rises, and new houses, shops and industries are built near the facility.
6. The new land use creates new trips, and the cycle starts again.

Example

A new highway is built to a town -> access improves -> land near the highway is developed for shops and housing -> more trips -> more traffic -> the road needs widening.

Importance

Transport and land use planning must be done together; otherwise urban sprawl, congestion and poor access result.