The discussion document, authored by expert RAE fellows, is aimed at evaluating which measures would be most effective and best value for money.
It comers as the DfT (Department for Transport) predicts road congestion will increase 55% by 2040, with the greatest increases on the strategic road network.
The paper considers over 20 possible measures but concludes that road pricing, technology-driven operator collaboration and extended delivery hours offer the best ways forward.
Looking at freight traffic, it singles out the inefficiencies of partially-loaded vehicles on city streets at peak times.
The RAE recommends re-timing deliveries to off-peak periods where possible.
It also suggests replacing car shopping trips with increased home delivery by retailers – updating aspects of competition law that hinder a more integrated home delivery network.
Beyond that, the challenge paper states that influencing times of travel and routes taken could alone achieve a substantial reduction in congestion without a significant decrease to the total volume of traffic.
It also observes that ‘smart motorways’, incorporating variable speed limits and use of hard shoulders, can also reduce congestion outside cities – but adds that they are expensive to implement.
“Our transport systems are struggling to cope,” comments Professor Andrew McNaughton FREng, who led the challenge group.
“Building new capacity is vital but not the universal answer... This challenge paper sets out how we can get on top of congestion, but only if we integrate technology advances and policy initiatives, and only if we act now.”