The carbon impacts depend on scheme by scheme decisions. We always assess the impacts on carbon of all major schemes as part of the NATA appraisal process. Carbon impacts will therefore be assessed as scheme proposals are developed in detail.
When deciding whether to increase road capacity to improve traffic flows and reduce congestion, we will take account of any impact this will have on the overall level of CO2 emissions from transport. In cases where we decide to go ahead with increasing capacity, we will build the CO2 impacts into our plans to keep CO2 emissions within the carbon budgets set under the Climate Change Bill.