Question to the Department for Transport:

To ask the Secretary of State for Transport, what assessment her Department has made of the potential impact of population changes due to immigration on public transport (a) capacity and (b) congestion levels in urban centres.

The Department models future demand for transport based on the Common Analytical Scenarios (CAS), which are a wide range of plausible scenarios related to population, the economy, behavioural change and decarbonisation. DfT publish the National Road Traffic Projections (NRTP) which are a set of estimates of road traffic using the CAS, these include estimates of urban congestion. Rail analysis also accounts for population and demographic change when estimating future capacity impacts. The population forecasts used at the DfT are published by the Office of National Statistics and include changes in population arising from births, deaths and immigration and other demographic changes.