Transport: Impact of different traffic policies on the high-street

Within transport, especially at local level, there are a number of competing imperatives; congestion, pollution, business, effective land-use. There are also different types and levels of intervention that can be made by local councils. In this case we developed a simple model (with dummy data) to demonstrate how system dynamics can be used to support decisions regarding transport policy & investments.

For a particular London Borough we identified that there was a balance between reducing congestion and not hindering the revenue of local business on the high street. To investigate this we developed a simple model covering:

•  The flow of cars onto the high street and into car parks
• The flow of buses onto the high street
• The flow of people from cars & buses onto the high street

The diagram below shows the part of the model related to the flow of cars.

Testing levels of parking restrictions

Using dummy data we ran the model with different types of traffic policies and interventions. Introducing restrictions on cars (i.e. restricted parking spaces) had a major effect on cars on the high street (obviously).

However, by including decision making on the choice between cars & buses we found that  minor restrictions actually increases the number of people on the high street (the reduction in cars is more than made up by extra people in buses) whereas major restrictions actually sees number of people falling (compared to the baseline).

Testing improvements in bus routes

Similarly, we used data from bus passenger surveys to model the change in usage due to different bus route times, the number of bus stops, combining car restrictions with increased bus frequencies.