A STUDY to determine the carbon impact of major road projects has provided evidence that is “confusing” and that “should not be used in decision-making.”

In 2020, West Yorkshire Combined Authority announced it would undergo a “carbon impact assessment” for all future road schemes to see if they would help or harm the environment.

The assessment would also look at the impact of previously approved road schemes.

The Authority’s Climate, Energy and Environment Committee discussed the study, and how a planned Bradford project would fare, at a meeting on Tuesday.

Matthew Page, a modelling analyst at the authority, told members that the assessment did not take a number of variables into account, including the shift to less polluting vehicles and the benefit of “active travel schemes” such as new cycle lanes.

Environmental impact of planned road schemes being reviewed

He said: “There is a huge amount of uncertainty in these findings.

“Overall the results are confusing, the numbers are difficult to understand and we have low confidence in most results.

“Given this uncertainty the numbers should not be used for decision making.”

He told members there were two types of carbon taken into account in the study, the carbon that will be produced as a result of the transport project, and the “capital carbon” – the carbon emitted during the construction of the scheme.

Many of the planned infrastructure schemes are found to be likely to increase carbon.

Mr Page said: “It is not just about the amount of carbon produced by a scheme. You have to look at what the carbon emissions would be without the scheme.”

As an example, he pointed to the assessment of the current Leeds flood alleviation scheme, which includes works currently being undertaken in Apperley Bridge.

The assessment finds the project will lead to an increase in carbon. But Mr Page told the meeting that the work would prevent floods – and each flood leads to huge amounts of carbon being released into the atmosphere.

Another scheme discussed at the meeting was the West Bradford Cycle Superhighway extension. Funded through the Government’s Transforming Cities Fund, the multi-million-pound project will see a new segregated cycle lane create between Bradford and Thornton.

The meeting heard that the assessment found this scheme would only have a small carbon benefit. However, Mr Page said this finding was based on existing car use and cyclist numbers. The hope was the scheme would get more people out of cars and cycling, which would improve carbon emissions and have wider benefits on health and congestion.

The findings will also be discussed at a full meeting of the Combined Authority this afternoon.